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RYU's "properly molested" NSX build thread

Ryu do you have a oil pan baffel? just wondering
Yes, the STMPO baffle. I had to choose between the SOS, Dali, and STMPO baffle. Unfortunately, I don't have the resources to properly test which one is better. I just had to rely on my common sense. It seems to be that the STMPO baffle design would work the best and the Dali being a close 2nd.
Awesome build! Can't wait to see whats next. and when the RYU custom exhaust setup becomes for sale!!! *hint hint nudge nudge*
Maybe one day when i've really got nothing to do! Thanks for the kind words :) One day i'll consolidate those exhaust threads here so maybe someone can be inspired to build their own. I uncorked it this wknd and the difference at the track was noticeable.
Regan, any chance you coming out to drive on Sunday? I need to check out one of my favorite nsx build :)
I don't think i'll be able to Greg. Might try to catch some surf since it's been a while since I haven't been chased by a shark.

I am. I also have twin Spal fans but would like a better radiator.
I'll chat with them and figure out minimum quantities to make this worth it for everyone.
Glad to see you on track! Jim's a great guy and is a great platform to test the radiator with high demands of a fast turbo car that actually races. Great to hear that your radiator outperformed a heavier Ron Davis.

Who had the PWR radiator and did they have proper ducting to a vented hood like on Jim's car?

For the NSX, i'm not a big fan of integrated oil coolers (in the rad). Unless the car is dry sumped or has a higher volume pump, sending pressurized oil all the way to the front of the car isn't ideal. Also, the integrated cooler injects a TON of heat into the radiator which takes away from the cooling ability of the coolant, while not always lowering the oil temps as well as a proper stand-alone air to oil cooler (although 239*F isn't bad atall so it must be cooling the oil pretty well at the expense of water temps).

Were the temp numbers (Jim's Ron vs. yours and the PWR) on the same day or temperature within 10*F?

9doors (Nick) has the PWR. Nick E. put it in for him I think. there is a pix floating around here by 9doors. A few months ago I saw the car, I don't remember he had ducting or a vented hood. I could be wrong by now.
+1 for Jim and, for that matter, our friend Jon Kuroyama. Both great guys to have in our community. Can't thank them enough for sharing their knowledge and friendship with me.

As far as the PWR radiator with integrated cooler, the oil overheating the coolant was our suspicion also. This was on 9Doors' 2000 NSX built by Jim, Nick (9doors) and Nick (Applied Motorsports). It's a really well put together car but it's still NA and those temps I quoted were from a CVR track day earlier in Nov (this month) that 9doors was kind enough to share with me. I'd be happy with those temps also, but i'm not sure what it would do if it's 110F ambient outside and where track temps are 140F+. I believe Nov temps at CVR were in the 80s? I think Nick has a top radiator "plate" that one of the vendors is selling here. It basically attempts to seal off the open cavity between the bumper beam and the core support. Though i'm not sure if he removed the OEM plastic shroud which directs air to the radiator very well also.

We have quite a bit of data logs to sift thru. Billy, you probably know better than I do that when attempting to compile the data logs from testing stuff like this there are so many variables involved that it's tough to provide a difinitive set of numbers. A particular challenge we had when attempting to provide test data in a controlled environment was to have all the cars there, under the same conditions, with the same setups. As hobbyist ourselves, we just didn't have the resources to make a bulletproof, pokeproof, haterproof, and trollproof set of data. All I can say now, is that this radiator is good enough for me!

With that said, Jim and I have tested on the same day but that was on a previous version at one of the hottest days at SOW in July. Track temps were 140'ish. That version had too dense of a fin configuration. The capacity was there to cool the coolant but was maxing out on airflow because cool down times took too long. Temps also started to creep up after about 2-3 hot laps which required a cool-down lap before going at it hard again. With our recommendation, MASiV tweaked the fin pitch and fin density on the latest version as well as reconfigure the tubes and softened up the water channels in the end tanks and we finally think we're happy with it. Jim got the first prototype late this summer (I got mine 2wks ago) but it was already late in the season whereby his local temps at Firebird had probably gone down 10-15F ambient or so. However, according to his logs, the same ambient conditions from previous years would yield 215F average on the Ron Davis and now yielding barely 205F on the latest MASiV rad. I just wish it was hot July/August temps so I could really test this out on something as crappy as the OEM fan. We know for sure we've got a winning solution with a non-shrouded twin fan configuration. At this point.. the fans are needed just for cool down laps or when sitting in traffic or otherwise in low speed conditions.

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Oh....one more thing Regan....ok, no lift kit, I think you should get a Giken.....its not ricey and nobody can see it.....its worth at least a second.:rolleyes:
Not sure if you're aware Tim but I built my own pneumatic lift kit before Steven had one available. I'm pretty happy with it so it'll be staying in my car for a while. I really like Steven's but i'd want to strip it down of all the electronics and limit any potential problem points. His works very very well but it's also quite complicated. I'm a "Honda" guy not a "Mercedes" hehe
<iframe width="420" height="315" src="//www.youtube.com/embed/1tejYJ24_lY" frameborder="0" allowfullscreen=""></iframe>

I put the switch in the center console in the JDM switch panel.
1401371_10151776016481588_1707759283_o.jpg


I'd love to get the OSG diff. That's actually close on my list as well as installing the JDM gearset with the USDM final drive. For my driving style I feel like that's the best compromise with 7psi of CTSC boost.

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Nice to see you're making a thread.


Could you tell me a little more on the AS Motorsports phenolic gaskets for the intake manifold and CTSC and how the install worked out?
Did you notice any difference in the AIT already? I'm going to get my manifold gaskets installed next week and the IAT sensors installed and am curious about your findings so far.
There are a few things I have yet to install (namely ASM Plate, DF front Fenders). I'm sort of going by necessity as a priority. It's coming into winter now which makes the phenolic plate a bit lower in the priority.


Here is what we talked about from a previous threads.






Going to go OT because not sure the OP even cares about this thread


cptnsx - Question for you please. What kind of cooling are you seeing in your IAT? Is it always relative to ambient? Say... your cooler will always cool IAT to +/- XX F degrees consistently regardless of ambient temps?


Here's my latest data points from my most recent track events this year.


- Streets of Willow ambient 110F/38C. With water injection resulted in IATs of 125F/52C. Delta 15F/14C
- Buttonwillow ambient 75F/24C. With water injection resulted in IATs of 100F/42C. Delta 25F/18C <<<---- This as today


I've been logging some amazing results especially today. I easily record deltas of 100F with the water injection turned off so only a 25F delta is more than I expected. The interesting surprise is I logged .5-1psi of increased boost today. My Autorotor typically maxes out at 7.1lbs in a typical sea level day. I was hitting near 8lbs of boost today at Buttonwillow. I recorded 38C of IAT at the time my boost is at it's highest. The water chilled air may have had a lot to do with it. Had to retune that section of the fuel map because didn't really expect it! I also thought the additional water would kill my HP but it seemed to have power for days. Car felt great all day long.


What's interesting is when it's off boost and the IAT begins to heat soak. I'll see cruising IATs of 60-65C.


Please share your results. My biggest concern is if my IATs are too cold. I might be willing to give up some cooler IAT if it means I dump less water into the cylinders. I believe you're on the SOS Laminova? If you're seeing this cool of IATs on your engine, it would make me feel better about a safety buffer in mine


My delta is 35-40F between ambient and highest temp; however, with the SOS Laminova not only is the IAT sensor different from stock but is also in a different location. Personally everything I have seen and read with Mustangs that use Meth or water cooling maxes out around 20-30 degrees.. maybe you're able to get better results or you could be over cooling the sensor. I have never seen that type of reduction. If your AFR still looks good and you are not bogging then you are not dumping too much water, technically this is suppose to reduce power since water does not burn.


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One way to test the IAT is to do about two to three third gear runs without the water injection and log your AFR. Then do about two to three with water injection and log your AFR. If you are getting a reduction of 75F then your AFR should be off by about a point ie your off injection should be richer by about a point.


thanks for the spot check cpt. i think you might be onto something in regards to the sensor overcooling. however, i'm not sure how to verify that. I'm reading from two IAT sensors. The OEM unit in the stock location via the CTSC manifold and an open element via one of the side ports connected to my Zeitronix data logger. The OEM is much slower moving but they both tend to get to the same delta. I'll have to trust it for now I reckon.


My AFR readings are a bit more inconsistent at WOT which might be due to too much water or maybe a worn out O2 WB sensor. I did experience some bog yesterday and turned down the water flow. So you're right there also. I think i'll be happy with a 30F delta so I need to order a couple more smaller nozzles. After turning down the spray and still getting only a 25F delta the car ran great and the AFR was more consistent. If I was lazy I'd be ok with keeping it as is but i'd like to turn up the pump voltage to max but maximize atomization with a smaller nozzle.


Thanks again!


Good to hear. I just changed out my wideband O2 sensors. I have heard that the AEM ones don't last a long time. I'm also running the iridium 8s with no problems. They have superior anti-fouling characteristics so you can get away with that. I've always heard run the coldest spark that does not foul to get extra detonation prevention headroom plus I mix 100 race gas with 91 to give me 93. I believe this 91 we get (probably from Cali) is not good. My G37S will lightly ping on it at low RPM. If I mix to get 92 or 93 for that car, everything is fine.
 
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Nice job Regan !...and you drive it well ! Its always a pleasure to share the track with you and I look forward to many more times out there with you.

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Geez, has it been that long already, LOL. How time fly's.

As Regan has said, he approached me and asked if I would be interested to start the testing on the new MASIV design when it was first thought of because of the higher RWHP numbers and hard racing I put my NSX through 12+ weekend events a year. Having known Regan on and off track and knowing how dedicated he is to the NSX community, I trusted him with this adventure so I made the commitment to him to see it all the way through from beginning to end, good or bad.

The journey took some patience, a lot of trial and error and some nail biting, but in the end was worth all the challenges we faced getting through it. I personally tested 3 of them before we finally arrived at the newest and our final version.

I had been using the Ron Davis for a couple of years prior to the start of testing for the MASIV. I was looking for something better. The Davis continually developed pin hole leaks and after several repairs I started looking at other options. The Davis would run anywhere from 210 to as high as 228 on track depending on the ambient temps. It must be also noted that I run a Laminova oil to water cooler so this adds even more stress on the cooling system. My oil temps would range anywhere from 235 to 265. Not all that great really and many times I would have to slow down and let things cool off. I looked at the PWR but didn't like the idea of oil to water cooling in the radiator itself with such close proximity. Looked at the dual pass radiator but decided after reading many of the reviews it wasn't something I was willing to spend the money on to try so at Regan's request seem like the best option for the long term. It was, and I am proud and honored to have been involved in this undertaking which has been met with great success that we shared.

As we begun the process with the first version, we found that the new MASIV needed more work as it's cooling efficiency lacked airflow during cool down periods sitting in the paddock so what we surmised the problem as needing stronger fans. Stronger fans were added to the first version and it didn't quite accomplish what we expected although we did see improvements. We were still having issues with long periods on track and some cooling down issues in the paddock. The 2nd generation with redesigned fin pitch and even with the stronger fans we still had issues that we finally related this to airflow after much discussion. (Me harping on Regan :) The next revision which incorporated the fin pitch & spacing and some modification to the tubes and tanks was the touchdown. With the resigned fin density and pitch it performed exactly what we were looking for. We found the sweet spot.

During this lengthy process we have seen a steady drop in temps on my car in coolant and oil temps throughout the process.
First version, water temps at 210 to 228, oil at 235 to 265 depending on ambient temps and 30 minutes sessions on track.
Second version, water temps at 200 to 220, oil at 225 to 255.
Third version (The one now after much conversation and redesign), water temps at 190 to 205, oil at 220 to 245. Ambient temps was 90 degree's

I couldn't be more impressed considering the rwhp I put down, the heat that's generated from running a turbo with this kind of rwhp, 30 minute track sessions of hard pounding on the NSX every lap and considering I run my oil through the coolant as an oil cooler. If it performs this well on my car all things considered, we knew it would perform even better on NA and SC NSX's since they would demand less cooling wise than my NSX demanded.

It has been a very amazing journey with Regan through this and I can't thank Regan enough for trusting me to undertake and be a part of this design with him.

We still have one more test to do. Regan this weekend will be installing his OEM hood back on his car (no ducting) with the single fan layout as the final test. If this goes as we feel it should now, they will be ready for the general NSX owners that want improved efficiency and cooling, whether they track their NSX's or just drive them on the street. I do both :)

The MASiV radiator is a heat exchanger i've helped developed for the last 3years. Jim (Coz) has been gracious enough to race with a prototype this season in his 600wHP, intercooled, laminova oil cooled, fully built race car. Jim is a great guy on and off the track btw. Can't say enough about him. After so much development we finally found a formula that works amazing in the NSX and it fits 100% like stock. Just imagine, Jim was running a thick 3-4" Ron Davis radiator core that was much thicker than stock and the MASiV radiator performed BETTER. We also have reason to believe (from local data as of last month) that the MASiV radiator is performing better than the PWR unit with the integrated oil cooler. I have tons of respect of Ron Davis as a company and heaps of respect for our Aussie PWR friends (they make F1 and basically most motorsports coolers you see on real race cars) yet the MASiV radiator is better (at least on the NSX). For example, in hot and dry Arizona weather, average ECT track temps on Jim's car was 215F with the big Ron Davis. He's now seeing average temps of no higher than 205F. A local friend is also using a new PWR radiator. It maxed at oil-239, max water-213 on an NA 3.2L. I've been testing this radiator with the OEM fan (Jim is using twin Spal fans). Our NSX OEM fan is so crappy it's incredible yet the rad is to be so efficient the OEM fan is adequate. It worked fine during cool down sessions at Buttonwillow this weekend albeit it was only 78F ambient. Regardless, I was seeing ECT track temps no higher than 77-82C and my car is supercharged. Pretty amazing.

I've asked the company to do a Group Buy here but the intent was to develop the fin technology with sales to the NSX market as secondary. I think with Coz Motorsports helping with the sales they'll do a small run for us. Not quite sure how many folks on here are even interested in a high quality radiator though.
 

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Sorry regan, it aint a tight car if it aint a Type R... lol

Man honestly you are one of my NSX idols, glad you are also local and couldn't thank you enough for all the help you give to me and the rest of the SoCal community..

I am sad to see though that my name was not mentioned even after the horchata and tacos I made for you :frown:
 
...and on a side note, I know the MASIV works :)

2013 Season end trophies
The race group season points have been calculated and posted.

The Time Trial Season points still require updates from CVR but I went ahead and manually calculated them and here is what I show for our season champions and top 3 that "qualified".
NOTE: Per the Supplemental Rules. The default points system will be used but to be eligible for a season end award, the competitor must attend at least 50% or more of the races in the same class. NOTE: Any/All disqualifications (DQ/DSQ) will not count as a race attended.

Please let us know if you see any errors or if your name is mis-spelled as this is how we will order the trophies and/or jackets.

Super Unlimited (SU)
1. Michael Papworth

Super Touring 3 (ST3)
1. Erik Davis

GTS3
1. Jeremy Renshaw

Honda Challenge 2 (HC2)
1. Eric Dayton
2. Team LBR
3. Team FTW

PTC
1. David Snyder
2. Justin Markiewicz

944 Spec
1. Rob Giorgio
2. Norm Hamden
3. Jeff Wojnar

TTU
1. Travis Barnes
2. Tony Szirka
3. Jim Cozzolino

TT1
1. Ken Gerhart
2. Chris Willson
3. Russell Whelan

TT2
1. Taylor Wilson
2. David Stark
3. Markos Mylonas

TT3
1. Jeremy Renshaw

TTB
1. David Schotz
2. Joel Schotz
3. Jason Griepentrog

TTC
1. Jeff Abrams
2. Aaron Hiar
3. Carson Clark

TTD
1. Robert Rose
2. Jay Ronquillo

TTE
1. Paul Bloomberg


NOTE: UMS Tuning Time Attack season results to TBA by Jon and/or Tony.
__________________
Tage Evanson
NASA Arizona - Regional Director
[email protected]
 
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Vented hoods and especially ones with proper ducting going from the back side of the radiator to the top of the hood/vent have a significant effect on the cooling efficiency of a radiator. Thus, you can't properly compare 9Door's PWR (assuming with a non vented hood) radiator's performance to your/Jim's Masiv radiator or say that it's "better" because its possible that the PWR still may be even better at cooling with the same ducting.

IIRC, the more fins per inch makes for a more efficient radiator, but the denser the fins, the quicker they plug up. As you mentioned, the thick Ron Davis has a greater capacity and it takes longer to get to equilibrium but if the Masiv has a better fin design and reaches a lower equilibrium sooner, its thinner core and lighter weight make for a much better combination.

Jim is a great guy and i'm glad you're testing the rad with a fast guy in a demanding environment. If you're radiator is as good or better for less than a RD then it's a no-brainer and a great product for the market. However i'm not sure it's fair to make claims about PWR when the test conditions were so different. They do make the best radiators on the planet and i'm not sure the spec of 9door's radiator but they can be ordered in any thickness, fin count, size, shape, etc... but you get what you pay for and they're a top level motorsport product and are priced accordingly. Keep up the good work testing and developing the Masiv! Do they come with non-painted fins?


Jim - Fan shrouding behind the radiator is good for the fan's cooling ability at low speeds but become a significant restriction at speeds above ~45mph. Mounting fan(s) directly to the radiator is often a good compromise for cooling at speed and in the pits. Also the more air-tight you can make the ducting from the front bumper to the radiator, then from the radiator to the hood, you'll see even larger gains in cooling efficiency than just having a vented hood alone.

Why not run an oil-air heat exchanger on the rear of your car rather than the laminova oil-water?
 
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Billy - Agree with you 100%. It's tough to make any kind of real comparison with the PWR. I've been very careful about comparing the PWR radiator. I have too much respect for that company and they are the pinnacle of Aluminum radiators in my mind. With that said, 9Doors is running a vented hood (not sure if ducted but safe bet, to say yes). Also, the MASiV radiator is a copper/brass design. Copper itself has approximately 30% better heat transfer coefficient than AL so there might lie the advantage since Nick ordered a drop-in replacement for 9Door's car IIRC. Copper is also heavier so the additional cooling is augmented by less desirable added weight.

Let's just look at the performance of the PWR in the way I intended to post it (not a MASiV vs. a PWR scenario)
* It wasn't that hot at CVR - Approx in the 80s F
* 9Doors car is a 2000 MY 3.2L NA with a Vented NSX-R Style hood
* It's got the built-in oil cooler
* It is well built/fabricated and of very high quality
* Temps on that day maxed at oil-239, max water-213 which are quite acceptable for the conditions of that day.

My Open Questions for the PWR:
* What if it was 100F+ outside or higher?
* What if the PWR was used in a OEM non-vented hood situation?

I don't think we'll ever get to a point of scientifically testing the one-off products on my car and Jim's for that matter. All we can do, is try our best at providing comparable data. You and I come from a data driven world and it's really annoying when people make claims, so I get it. Hence, if you read all my post I've been careful about making any blanket statements.

All I can do is put my name behind it (and maybe Jim's too) for whatever that is worth. Owners will have to take the risk and try for themselves and see if it works for them. If they don't, then they don't.

At any rate, more proven products for our rare cars is a good thing for everybody.
 
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Thank you for clarifying and I too am just trying to help and think logically. I didn't know the Masiv was copper! Very cool, sounds like a great product.

I don't believe track temps are that helpful since a car will run cooler during a session later in the day where ambient temps have dropped but track temps are still relatively high from earlier in the day. So i'd probably look at ambient temps as the barometer for tests.

I'm not sure what would happen with the PWR in 100*F weather, I also don't know 9Doors or if he pushes his car to 100% like Jim does -more variables. The best thing would be on the same day & session to get comparable numbers -preferably datalogged to see what the sustained temp is, not just from a short session or a brief spike when the car is brought into the pits.
 
Thank you for clarifying and I too am just trying to help and think logically. I didn't know the Masiv was copper! Very cool, sounds like a great product.

I don't believe track temps are that helpful since a car will run cooler during a session later in the day where ambient temps have dropped but track temps are still relatively high from earlier in the day. So i'd probably look at ambient temps as the barometer for tests.

I'm not sure what would happen with the PWR in 100*F weather, I also don't know 9Doors or if he pushes his car to 100% like Jim does -more variables. The best thing would be on the same day & session to get comparable numbers -preferably datalogged to see what the sustained temp is, not just from a short session or a brief spike when the car is brought into the pits.
Excellent point here! This hadn't even crossed my mind. I'll ask 9doors if he can comment on the sustained temps.

I remember from this wknd that on the track (with the MASiV radiator) I sustained temps of 77C-80C at around noon time for the 20min session. However, as i pulled into the pits my temps shot up to 85C. Though 85C is still only 185F so still relatively cool. I think at this point the bottleneck was the stock fan.

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granted, I also haven't learned to drive my car as hard as say... IllWillem, Ryan, Jim, or yourself... but i'm getting there!
 
You don't want to have your temps too low (too much below 180*F). And keep in mind, fans are only good for low speeds in the pits or stop and go traffic, they are actually bottlenecks when you're going faster than 45mph.

Keep me posted as i'm interested in the pricing and may even get a Masiv radiator for my personal car :)
 
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Agree there too. Too low is no good. I actually notice my street temps pegged exactly at 80C during cruising conditions. That makes me think the thermostat is doing a lot work just trying to maintain the engine warm. I guess that's a good problem to have and can be controlled with a shroud later on. I'll worry about that later.

I'll update this thread accordingly. Glad you think the work we're doing is worthwhile!
 
Hi,

thanks man... also very interested, depending on price (you can ballpark me through PM, +/- $100, so i know what i can expect)

Thanks,
Nuno
 
Regan, you are so kind to mention me and my setup and I'll continue to give you PWR temps as long as you want/need them.

For some clarity, I won't go into the sorted history of my temp issues (i'm on my 4th radiator) unless someone asks. I now have:

PWR Radiator with integrated oil cooler
Dual 1300cfm fans
Still have the OEM ducting for the rad
The top coolant shield which is also supposed to force air through the rad
Dali's hood duct to force air out of the:
VIS type-R (not deep dish unfortunately) hood.
Front undertray is not yet sealed (should be in a month or so)
Difflow difuser (with other underbody stuff) only exposes oil pan, tranny, and headers
Dali's oversized, baffled oil pan
Dash12 lines up the tunnel to the oil cooler
I run a water/coolant mixture w/water wetter that has a freezing point of 20 degrees

Oil temps are measured on the hose leaving the cooler.
Water temps are on one (sorry I forget exactly which) of the large return hoses next to the overflow tank.

My temps reported to Regan (and Nick) have been from the Max recorded on the SPA gauges. I would safely say that sustained temps are lower.

Compared to what I was dealing with before I'm so far very happy with this system, though had the Masiv been available I'm sure I would have tried it.
 
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Oil temps are measured on the hose leaving the cooler.
Water temps are on one (sorry I forget exactly which) of the large return hoses next to the overflow tank.
Thanks for chiming in Nick! Can I ask a clarification. If you're measuring the temps at the hose leaving the cooler then effectively the oil temps of 239F is already after the oil has been cooled by the cooler? Any idea what the hot oil temp is.

I would safely say that sustained temps are lower.
That's awesome. Yes, I was initially a bit surprised at the oil temp but after Billy mentioned its the peak vs. sustained it occured to me your sustained avg temps are likely lower.

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btw.. i'd keep that setup. if it ain't broke, don't fix it! From what I saw your car is very well built with quality parts.

Can't wait to get out to Big Willow with you in Dec.
 
Billy,

As always, hope you and Kristy are well.
Look forward to seeing you very soon out at SM for the testing on the Shanghai car.
It should be a very nice casual weekend and I look forward to some feedback on my set up (you driving my NSX) and some coaching (Me driving my NSX) from you on track both ways :)
I've known you and listen to your advice and guidance for years and there's no one else I trust more. While I will never be as fast as you are, which is amazingly fast, how fast I have managed to get is because of your help, advise and guidence along the way getting me to where I am. I look forward to seeing you, it's been to long since we've had the opportunity to spend some quality face to face time together on and off track. I hope Kristy can make it out to SM with you as well.

Right now my dual Spa's are mounted appox 1/2" off the radiator. I actually re-fabricated the shroud that came with the Mitsumoto fans and used it. I also drilled several 1.5" and 2.5" holes in the shroud to allow more air to pass through it and lessen the restriction the shroud causes. The shroud became nothing more than a mounting platform for the fans.

One thing I haven't done yet, which I will do before the start of next season is fabricate a duct that channels air from the back side of the radiator up and out the vent on the hood.
I have sealed the top of the radiator to the top chassis beam, but not the sides. Something else I need to do as well before next season.

As for the air to oil cooler. I have been seriously considering losing my AC and actually use the AC condensers in the front of of the car as oil coolers instead of the Laminova.
What do you think of this idea ?



Vented hoods and especially ones with proper ducting going from the back side of the radiator to the top of the hood/vent have a significant effect on the cooling efficiency of a radiator. Thus, you can't properly compare 9Door's PWR (assuming with a non vented hood) radiator's performance to your/Jim's Masiv radiator or say that it's "better" because its possible that the PWR still may be even better at cooling with the same ducting.

IIRC, the more fins per inch makes for a more efficient radiator, but the denser the fins, the quicker they plug up. As you mentioned, the thick Ron Davis has a greater capacity and it takes longer to get to equilibrium but if the Masiv has a better fin design and reaches a lower equilibrium sooner, its thinner core and lighter weight make for a much better combination.

Jim is a great guy and i'm glad you're testing the rad with a fast guy in a demanding environment. If you're radiator is as good or better for less than a RD then it's a no-brainer and a great product for the market. However i'm not sure it's fair to make claims about PWR when the test conditions were so different. They do make the best radiators on the planet and i'm not sure the spec of 9door's radiator but they can be ordered in any thickness, fin count, size, shape, etc... but you get what you pay for and they're a top level motorsport product and are priced accordingly. Keep up the good work testing and developing the Masiv! Do they come with non-painted fins?


Jim - Fan shrouding behind the radiator is good for the fan's cooling ability at low speeds but become a significant restriction at speeds above ~45mph. Mounting fan(s) directly to the radiator is often a good compromise for cooling at speed and in the pits. Also the more air-tight you can make the ducting from the front bumper to the radiator, then from the radiator to the hood, you'll see even larger gains in cooling efficiency than just having a vented hood alone.

Why not run an oil-air heat exchanger on the rear of your car rather than the laminova oil-water?

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For what it's worth, I stand behind it as well. Using it should say enough :)

All I can do is put my name behind it (and maybe Jim's too) for whatever that is worth. Owners will have to take the risk and try for themselves and see if it works for them. If they don't, then they don't.

At any rate, more proven products for our rare cars is a good thing for everybody.
 

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Coz - Thank you for the kind words. I'm looking forward to testing your and Shanghai's cars hopefully sooner than later! Kristy will hopefully come out as well. I'm also antsy about my motor build.

That shroud should work alright. FWIW, removing the fan itself will improve your cooling at speed by a noticeable amount. If 1 fan is enough to keep your engine cool at low speeds or when parked, you can improve your overall efficiency by removing a fan. But this takes testing (or simply unplugging one to see if its enough before removing one).

Taping up the big gaps will help but once you make the sealing AIR TIGHT from bumper-radiator then radiator-hood, you'll see HUGE gains in cooling and front downforce.

Why not mount an air-oil cooler in the rear of your car and duct your side vents to the oil cooler?
 
Coz - Thank you for the kind words. I'm looking forward to testing your and Shanghai's cars hopefully sooner than later! Kristy will hopefully come out as well. I'm also antsy about my motor build.

That shroud should work alright. FWIW, removing the fan itself will improve your cooling at speed by a noticeable amount. If 1 fan is enough to keep your engine cool at low speeds or when parked, you can improve your overall efficiency by removing a fan. But this takes testing (or simply unplugging one to see if its enough before removing one).

Taping up the big gaps will help but once you make the sealing AIR TIGHT from bumper-radiator then radiator-hood, you'll see HUGE gains in cooling and front downforce.

Why not mount an air-oil cooler in the rear of your car and duct your side vents to the oil cooler?
We tested with one fan. Actually between Jim and I we tested about 8 different configurations (maybe more.. lost count). The problem with 1 fan and no shroud is that sitting in traffic or at low speeds the fan simply isn't cooling enough fin surface area of the radiator. This would not be a problem if the NSX had a radiator configuration which the end tanks on the sides (instead of on the top and bottom). We actually thought of doing this but the mounting and coolant tube layout made it a pain in the ass for the gain. If it's at the top and bottom, placing one fan leaves too many tubes whereby the coolant tubes that does not cross the path of the fan simply doesn't get cooled at all and recirculates back into the system hot. The best one fan configuration i've tried is mounting a Spal fan using the OEM shroud (which still leaves some fins exposed to free air on the sides). Ideally, I'd like to build a shroud with lightweight flaps. This way when the fan is on the flaps close thru vacuum but when the air flow is high (as in high speed driving) the flaps open and let the hot air escape. Obviously, this takes a lot more testing but both Nick (@ Applied) seems to like this idea. I haven't gone down this path because it seems the OEM fan configuration seems to work well in my car. We'll have to see how it works when it's ridiculous hot out. I'm almost tempted just to put two fans in there and call it day and go tracking! However, I was hoping to keep the ABS, even if upgraded to a 00+ newer unit whereby you have to use a slim fan on the driver's side because the ABS unit leaves little room for a full size paddle or turbine style fan due to the ABS unit and the "cage" around it.
 
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Glad to see you on track! Jim's a great guy and is a great platform to test the radiator with high demands of a fast turbo car that actually races. Great to hear that your radiator outperformed a heavier Ron Davis.

Who had the PWR radiator and did they have proper ducting to a vented hood like on Jim's car?

For the NSX, i'm not a big fan of integrated oil coolers (in the rad). Unless the car is dry sumped or has a higher volume pump, sending pressurized oil all the way to the front of the car isn't ideal. Also, the integrated cooler injects a TON of heat into the radiator which takes away from the cooling ability of the coolant, while not always lowering the oil temps as well as a proper stand-alone air to oil cooler (although 239*F isn't bad atall so it must be cooling the oil pretty well at the expense of water temps).

Were the temp numbers (Jim's Ron vs. yours and the PWR) on the same day or temperature within 10*F?
I'm with you on the oil cooler part.
Not only the pressure and inefficiency the added risk of oil leaks is not worth it.

Back on topic,
Very very nice build! keep up the great work.
 
The car would start to overheat with 1 fan at low speeds? Was the (1 remaining fan that was running) mounted flush to the radiator?

If you just remove one of the 2 fans on Jim's shroud, the remaining fan would suck air from the opening (or even the other fan if its' just unplugged -defeating my last post/recommendation) rather than sucking the air through the fins of the radiator -because of the 1/2" gap between the fan and the rad.

If you have 2 fans mounted flush to the fins, they would probably work the same as the 2 fans in jim's shroud, but would be slightly better at speed due to the lack of a shroud. However, 1 fan mounted to Jim's shroud would be useless whereas 1 fan mounted directly to the fins may be enough for your needs.

With this in mind, how did you test the multiple fan configs?
 
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The car would start to overheat with 1 fan at low speeds? Was the (1 remaining fan that was running) mounted flush to the radiator?

If you just remove one of the 2 fans on Jim's shroud, the remaining fan would suck air from the opening (or even the other fan if its' just unplugged -defeating my last post/recommendation) rather than sucking the air through the fins of the radiator -because of the 1/2" gap between the fan and the rad.

If you have 2 fans mounted flush to the fins, they would probably work the same as the 2 fans in jim's shroud, but would be slightly better at speed due to the lack of a shroud. However, 1 fan mounted to Jim's shroud would be useless whereas 1 fan mounted directly to the fins may be enough for your needs.

With this in mind, how did you test the multiple fan configs?
Yes, at low speeds (i.e. heavy fwy stop/go traffic) the car would overheat with a 1 fan, no shroud configuration. Again, this was with our Version 2 radiator. Not the most recent Version 3 though I suspect the problem would still be the same. It was mounted whereby the fan blades were 5-10mm away from touching the fins/core. This was per the recommendation of Spal and another OEM fan manufacturer we consulted with. So I think you're saying the fan housing should make contact with the core.

I'll argue that with a 1 fan configuration, no shroud, in a low speed situation, you run into this problem in the NSX (see diagram). The OEM end tank configuration, which I eluded to the previous post, has the problem I tried to illustrate in the diagram below. The arrows represent water flow and water temp.

Radiator Fan Config (single fan) 2.jpg
 
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Yes, at low speeds (i.e. heavy fwy stop/go traffic) the car would overheat with a 1 fan, no shroud configuration. Again, this was with our Version 2 radiator. Not the most recent Version 3 though I suspect the problem would still be the same. It was mounted whereby the fan blades were 5-10mm away from touching the fins/core. This was per the recommendation of Spal and another OEM fan manufacturer we consulted with. So I think you're saying the fan housing should make contact with the core.

I'll argue that with a 1 fan configuration, no shroud, you run into this problem in the NSX. The OEM end tank configuration, which I eluded to the previous post, has the problem I tried to illustrate in the diagram below. The arrows represent water flow and water temp.

View attachment 107316
Can you send a link to where they recommend the 1cm gap? I've mounted spals on my street cars flush, there's SPAL hardware that has zip-tie like prongs that go through the fins of the radiator to mount the fan flush, and all of the racecars i've seen have the fans mounted flush. IMO that gap greatly affects the cooling ability of the fan which could explain your issues since air takes the path of least resistance and will be sucked in from that gap rather than from through the core of the rad.

The FXMD NSX has 1 (16"?) fan and it keeps it plenty cool at idle after coming in hot on track.

You mentioned the radiator end tanks a few times. What's the issue with the top & bottom end tank configuration like a stock NSX? I believe the hot water goes in the top and out of the bottom like most production cars.
 
Not to derail but that HKS box is a piggyback, right? Meaning you have retained the stock ECU?

I know plug-and-play wiring harnesses for NSX exist for AEM FIC, but I'm assuming you had to make one (or get one made) for the HKS?
 
i think we're talking two different things in terms of the spacing. they said the distance from the fan blade's leading edge needs to be between 5-10mm. they did not specify the spacing of the fan housing itself. They have fans with different housing specifications for custom applications so we had to be specific. So.... I think we're talking the same thing here.. i agree, that if you're saying the fan housing should be near or touching the core, it will be more efficient.

in terms of the end tanks discussion.. i'm not sure how much more I can better illustrate my theory than the diagram I put together. Sorry man.. i'm just not that smart - small brain syndrome :)

Will reply more when I get home tonight. Will try to take pics too. Will also try to test with a 1 fan, no shroud situation soon... though, like I said before... I've been having enough success with the OEM Fan configuration so the need to do more testing is not as important.

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Not to derail but that HKS box is a piggyback, right? Meaning you have retained the stock ECU?

I know plug-and-play wiring harnesses for NSX exist for AEM FIC, but I'm assuming you had to make one (or get one made) for the HKS?
Yes. Actually the HKS F-Con iS is a pure piggyback. I'm considering upgrading to a HKS F-Con VPro which can function as a piggyback or a full stand-alone. As I get more educated on tuning, I just want to do more and more. It's a disease! haha

The HKS units are really very good and a quite a robust platform. The problem is finding a good tuner who's familiar with it.

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This was our 2nd dyno session. The iS has a nice feature and displays sensor outputs via a composite video out signal.
5756_10151530139556588_1672693539_n.jpg
 
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i think we're talking two different things in terms of the spacing. they said the distance from the fan blade's leading edge needs to be between 5-10mm. they did not specify the spacing of the fan housing itself. They have fans with different housing specifications for custom applications so we had to be specific. So.... I think we're talking the same thing here.. i agree, that if you're saying the fan housing should be near or touching the core, it will be more efficient.

in terms of the end tanks discussion.. i'm not sure how much more I can better illustrate my theory than the diagram I put together. Sorry man.. i'm just not that smart - small brain syndrome :)

Will reply more when I get home tonight. Will try to take pics too. Will also try to test with a 1 fan, no shroud situation soon... though, like I said before... I've been having enough success with the OEM Fan configuration so the need to do more testing is not as important.
Jim's shroud looks to space the face of the fan about 0.5-0.75" away from the face of the radiator. In this case, there is 0.5-0.75" of a gap where the fan will suck air from instead of through the radiator fins if the second fan is removed or unplugged. If there is ANY gap between the outer edges of the fan housing and the face of the radiator fins, then it will greatly affect the cooling ability of the fan.

For a SPAL fan, you want to mount the face directly to the fins, or have an air tight seal from the outer edges of the fan to the face of the shield.

On another note, for the end tanks, I think you drew the diagram wrong for the top/bottom end tank design. I believe all production cars have the hot water go IN the TOP then the cooled water comes OUT of the BOTTOM. Could you elaborate on how the cross flow radiator cools better than the top-down?
 
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