Semi-DIY Mild Engine Build for FI

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Location
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Hello,

The purpose of this thread is to document my engine "build." As the older cars like mine are getting a bunch of miles on them, and a lot of us are interested in forced induction, I thought this might be informative for a lot of DIY'ers. There seems to be a bunch of folks that have power aspirations in the 400-450WHP range. This seems to be a sweet spot as far as driveability, drivetrain longevity, and also money invested in the engine to do so reliably. Beyond this power level, IMO, it gets really expensive with sleeving the block, aftermarket connecting rods, aftermarket main caps, aftermarket optimized cams, etc.

I've never rebuilt an engine before but wanted to learn (gotta learn sometime). Instead of shipping the car off, I'd like to tear it down myself, do the short block assembly (after the block is bored, honed, and decked, and the rotating assembly is balanced), and final engine assembly. I don't think I'm going to tackle the heads myself though. I will just ship those off to be reworked. Doing this won't save much money, but will save some. But I'll learn a lot (I already have in my reading and asking a bunch of questions) and I get to buy more tools :smile:

This isn't something that should be tackled by a lot of folks. But, if you're somewhat mechanically inclined, have patience, have some time where you're not in a rush, and ask questions when you're unsure, then you can probably do this too. Having said that, I hope I don't screw mine up and it works in the end :biggrin: I certainly don't know everything and I will be asking a lot of questions in this thread. A lot of our NSX experts have already answered a lot of my questions in other threads, I'll try to link to those when the time comes. Hopefully this will help others....

This will follow along the lines of Tuan's (gsrboy) epic engine removal thread here:
http://nsxprime.com/forum/showthread.php?t=128469

SOS has also done a nice pictorial of the rough steps they do when performing an engine build here and in past NSXCA magazines:
http://nsxprime.com/forum/showthread.php?p=1498484#post1498484



So, this is what I've got:
I have a '92 3.0L M/T NSX with ~130k miles. The engine runs great, doesn't burn oil or leak it (minor weeping though), but it is time for TB/WP, hoses, harmonic balancer, main seals, etc...


And this is where I plan to be:
I want ~450WHP, so this is the perfect time to upgrade the common weak link in this engine to accomodate it (OEM cast pistons). To get the 450WHP, I will be making a custom turbocharged setup. I'm designing it now, but this will come later after I get the new engine broken in and learn how to work the AEM EMS. And if I have enough money to finish all of it :redface:


This is my current inventory of parts:
- All new OEM stuff purchased from the great guys at Acura of Augusta:
Hoses
Engine gasket kit
TB/WP, timing belt tensioner
Harmonic balancer
Vehicle speed sensor
It's highly recommended you check inventory before taking things apart! I didn't have much wait time, but others have in the past for the OEM parts.

- Stuff from SOS:
90.5mm 10.2:1CR Wiseco pistons with xylan skirt coating and ceramic coated domes
'97+ LMA conversion
MLS standard thickness head gaskets
ARP head studs
Walbro fuel pump
RPS twin carbon clutch (overkill - SOS sport clutch may be better suited)

- Dali's Billet Steel Oil Pump Gear
http://www.daliracing.com/v666-5/catalog/index_browse_part.cfm?focus=1078

- OEM Denso-rebuilt starter from Amazon
http://www.amazon.com/gp/product/B000C5SGJU/ref=oh_o03_s00_i00_details

- Autowave's Series 2 AEM EMS with dual UEGO O2 sensors
http://nsxprime.com/forum/showthread.php?t=150818

- A bunch of stuff purchased from Summit, like dial bore indicator, plastigage, engine block cleaning kits, Clevite77 bearing guard, 90.5mm bore billet piston ring compressor, piston ring filer and pliers, etc.

- Also have a bunch of shop rags, brushes, degreasers, zip-loc bags, and dedicated camera/computer to take a bunch of pics as it's pulled apart!


By limiting the power to ~500 crank HP, I don't need to sleeve the engine, do a bore using deck plates, do a main bore, don't need main caps, etc. Also going to keep the OEM cams, maybe keep the OEM valves, but upgrade or replace the springs/seats/retainers, and valve seals and guides. I'm unsure how much will be removed from my block and heads when they're decked, so I might need adjustable cam gears. I'm trying to avoid that by taking a little hit in power for not having to degree the cams and do all that timing stuff later during assembly. This will all be explained at the appropriate times in the build.


I'll also be doing a lot of other things later when it goes back together, like:
Upgrading the cooling system (aftermarket radiator, coolant temp sensor). Deleting VVIS, EGR, crankcase ventilation, and simplifying the OEM throttle body. For oil I already have Titanium Dave's baffled oil pan and temp/pressure senders/gauges. I will probably add an Accusump. Fuel pump, filter, and rail mods (ID1000 injectors will come later after break-in). Transmission works great and was rebuilt 6 years ago for snap ring fix with case, bearings, and new synchros, so I'm not touching it. Wish it had JDM short gears , but that’s a long story….






1st Step is READ!!!
The Service Manual shows how to remove/install the engine and disassemble/reassemble it. Read through this stuff, but remember - don’t ever separate ball joints!

If you want some other reading material with color pictures, our C-series engines are most familiar to the B-series. This is the book I bought:
http://www.amazon.com/gp/product/1932494782/ref=oh_o01_s00_i00_details




2nd Step is More Reading and Research!!!
The first step should have raised a bunch of further questions, like, detailed instructions for piston ring gapping, rotating assembly balancing, what do I really need to replace or machine, etc? That’s where doing a bunch of internet searches comes in. You should also start searching for machine shops where you can take your block and rotating parts to do machining and balancing. Admittedly, I don’t have this figured out yet. There’s two local places I need to interview tomorrow on my day off, but at worse case, you can always box and ship everything out to known trusted shops.

I also did a baseline dyno on a local Dynojet. I expect to get this thing running and broken-in and ready to dyno in the Spring under similar weather conditions. I’m not concerned with absolute power numbers since all dynos are different – just relative numbers to make before/after comparisons. This isn’t necessary. Just thought it would be fun since I’ve never had it on a dyno and wanted to get an idea of A/F ratios. I’m glad it didn’t blow up:
Baseline_Stock_1024x745_.jpg





3rd Step is Preparation!!!
After you’ve read and have a good idea on what you’ll need to do, then start deciding what you want to buy and basically how much you want to spend. Start stockpiling parts beforehand so you possibly won’t have to wait a long time when you need something. The basic ones have been listed previously. Now you need tools, a clean, organized, well-lit place to work on this stuff, rags, degreasers, etc.

You also need a method to lift the car and drop the engine, and an engine stand. I don’t have space or the money for my dream two-post asymmetric lift, so I bought this engine lift to support the engine/transaxle/subframe while it’s lowered down onto dollies, and then lift the rear of the car to roll this stuff out:
http://www.northerntool.com/shop/tools/product_200305213_200305213

Then, I bought this engine stand to support the engine for cleaning and teardown:
http://www.northerntool.com/shop/tools/product_200313359_200313359

Unfortunately, I waited almost two weeks for the engine stand to arrive at my local store, and then noticed some fitup problems with it. Some freak thing I guess. Ordered a replacement last night…. It’s OK since I’m waiting for my Series 2 AEM EMS from Autowave to arrive. Mike is putting his calibration for their shop NSX with intake/headers/exhaust on it. With the dual UEGO O2 sensor feedback it should be good to putt around in for a few days over Thanksgiving! I’d like to get the EMS installed and running over break before tearing the car apart. Just to learn the AEMTuner software and play around with some things.



Plan is to take the car apart right after Thanksgiving. Stay tuned... I’ve put a lot of thought into exactly how to get the car up safely in the air and remove all this stuff. Should be interesting to see if it works! I’ll take plenty of pictures.

Dave
 
90.5mm 10.2:1CR Wiseco pistons with xylan skirt coating and ceramic coated domes
'97+ LMA conversion
MLS standard thickness head gaskets
ARP head studs
Walbro fuel pump
RPS twin carbon clutch (overkill - SOS sport clutch may be better suited)

- Dali's Billet Steel Oil Pump Gear
http://www.daliracing.com/v666-5/catalog/index_browse_part.cfm?focus=1078

- Autowave's Series 2 AEM EMS with dual UEGO O2 sensors
http://nsxprime.com/forum/showthread.php?t=150818

By limiting the power to ~500 crank HP, I don't need to sleeve the engine, do a bore using deck plates, do a main bore, don't need main caps, etc. Also going to keep the OEM cams, maybe keep the OEM valves, but upgrade or replace the springs/seats/retainers, and valve seals and guides......

Great thread.

I just got a call from my service center and my engine is in the process of being dropped as I type this. it should be ready for delivery to the machine shop tomorrow or some time next week.

How much boost are you planning on running?

According to SOS's Piston section and your power goals, I think you may want to reconsider the compression ratio from a 10.2 to a 9.5 to be safer. Also, since you are using MLS gaskets you will need to shave the bottom of the head where it meets the gaskets to have an even contact patch/ This will effectively increase your compression ratios as the volume of your combustion chambers shrink in size.

9.5:1 CR (forced induction: 400-500 wheel horsepower)
10.2:1 CR (factory or forced induction: up to 400 wheel horsepower)

I've got a similar list of components and power goals in my build. However, I'm going to have a better accessment once the engine is pulled apart if there are any additional parts needed.

I do plan on upgrading to the Ferrea valves since they are suppose to be a few grams lighter, but most importantly, my flow-bench tests will help me determine if I need undercut valves or not for the intake portion. the other added benefit is that the Ferrea valves will help preserve the engine in the unfortunate event that the valves and piston were to contact from either a failed spring, mis-shift, etc. the valves are known to bend and not break off in the combustion chamber, which will almost certainly cause much greater damage.

For my rebuild I'm going to use the Power Enterprise Kevlar Timing belt

http://powerenterpriseusa.net/products/engine/timing_belt/timing_belt.htm

Also, have you considered the locking timing belt tensioner?
 
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According to SOS's Piston section and your power goals, I think you may want to reconsider the compression ratio from a 10.2 to a 9.5 to be safer. Also, since you are using MLS gaskets you will need to shave the bottom of the head where it meets the gaskets to have an even contact patch/ This will effectively increase your compression ratios as the volume of your combustion chambers shrink in size.

I intentionally wanted to keep the OEM CR for a few reasons. Just in case I decided to do direct port nitrous injection through the old EGR ports instead of turbo :wink:... and also because I'm going to use methanol injection when going FI. It works pretty well! Finally, I've already got the pistons too.



I do plan on upgrading to the Ferrea valves since they are suppose to be a few grams lighter, but most importantly, my flow-bench tests will help me determine if I need undercut valves or not for the intake portion. the other added benefit is that the Ferrea valves will help preserve the engine in the unfortunate event that the valves and piston were to contact from either a failed spring, mis-shift, etc. the valves are known to bend and not break off in the combustion chamber, which will almost certainly cause much greater damage.

Also, have you considered the locking timing belt tensioner?

Cool, please let me know how the valves work out! Are you doing the "typical" 1mm diameter oversize on the intake (like the 3.2L engines)?


Good call on the locking timing belt tensioner. The SOS one is ~$275 shipped, whereas I bought a new OEM one for $92 shipped :wink: I plan on doing the "locking part" mod described here for just a few more $:
http://ojas.net/nsx/mirror/dal#Timing Belt

Dave
 
Nice ,I will follow this thread since is very similar to a built I plan.

Plus two on the billet caps and ofcourse all of the ARP hardware.
Good luck.

-MSR

Thanks!

I have ARP studs for the head. I was considering ARP rod bolts, but decided against it. I plan on just inspecting my OEM ones and measuring them to see if they're within spec. Then just reuse them with new nuts. If I went with ARP rod bolts I would have to get everything align bored, and then that could get into different rod bearings, etc. I plan on just using plastigage to confirm my clearances using new OEM rod bearings.

If I were building a 600HP beast that would see severe track usage, I would do the ARP rod bolts, and billet main caps (below), but right now I have to draw the line soemwhere on the costs for this "measly" 450WHP build.




Consider Billet Main Caps.

This was my motor. I was lucky, this failure could have destroyed the block and crank.
http://nsxprime.com/forum/showthread.php?t=143947

Thank you! I have considered them. Then I found out the $600 for the caps would be in addition to a block align bore, and then getting into the process of selecting main bearings (like the rod bearings I was talking about above). All of that will push the short block work and assembly out of my league. Like I said above, I have to draw the line somewhere on this build... I just hope later that it won't come back to bite me! If it does, I'll do a K20 swap or ditch the whole car for a Factory 5 GTM :wink:

I am doing a couple of things though to minimize main cracking:
- I'm researching what kind of chamfer I can put on the oiling holes to help avoid the stress risers that may lead to cracking.
- I'm also balancing the rotating assembly to minimize the loads in the first place.

That's one thing SOS doesn't mention when selling the main caps. The slightest imbalance puts additional stresses on the crank and mains. Maybe the few cars that have had problems had out-of-balance rotating assemblies (clutch, flywheel, crank, pistons, etc), and they failed after repeated use on the track :confused:

Dave
 
......Cool, please let me know how the valves work out! Are you doing the "typical" 1mm diameter oversize on the intake (like the 3.2L engines)?.....Dave

I'm going to see if the shop received the block so I can swing by and take a look at it when it's fully pulled apart. Yes, only it it will fit. I heard that the 3.2 valves run really close to the sleeves. Should I be worried?

Consider Billet Main Caps.

This was my motor. I was lucky, this failure could have destroyed the block and crank.


http://nsxprime.com/forum/showthread.php?t=143947

How much power were you running when the main caps were discovered to be broken?

Thanks!

I have ARP studs for the head. I was considering ARP rod bolts, but decided against it. I plan on just inspecting my OEM ones and measuring them to see if they're within spec. Then just reuse them with new nuts. If I went with ARP rod bolts I would have to get everything align bored, and then that could get into different rod bearings, etc. I plan on just using plastigage to confirm my clearances using new OEM rod bearings.

If I were building a 600HP beast that would see severe track usage, I would do the ARP rod bolts, and billet main caps (below), but right now I have to draw the line soemwhere on the costs for this "measly" 450WHP build.

Thank you! I have considered them. Then I found out the $600 for the caps would be in addition to a block align bore, and then getting into the process of selecting main bearings (like the rod bearings I was talking about above). All of that will push the short block work and assembly out of my league. Like I said above, I have to draw the line somewhere on this build.....

I am doing a couple of things though to minimize main cracking:
- I'm researching what kind of chamfer I can put on the oiling holes to help avoid the stress risers that may lead to cracking.
- I'm also balancing the rotating assembly to minimize the loads in the first place.

That's one thing SOS doesn't mention when selling the main caps. The slightest imbalance puts additional stresses on the crank and mains. Maybe the few cars that have had problems had out-of-balance rotating assemblies (clutch, flywheel, crank, pistons, etc), and they failed after repeated use on the track :confused:

Dave


I do plan on upgrading my rod bolts to the ARP ones. My concern was if the OEM bolts were to stretch and you spin a bearing and/or make the main caps crack.

I didn't realize that there would be other stuff that needs to be replaced in the event of upgrading to ARP bolts.

I'm on the same fence for the billet main caps and it does make sense with regards to balancing the engine properly, which is part of all my engine builds.

SOS only mentions Main cap upgrades in the higher horsepower Stage 2 & 3 rebuilds as an option.

Since my goals are to make whatever power at i bar of boost (14.7 psi) I don't think i will see 580HP that is rated for their stage 1 rebuild.
 
I'm going to see if the shop received the block so I can swing by and take a look at it when it's fully pulled apart. Yes, only it it will fit. I heard that the 3.2 valves run really close to the sleeves. Should I be worried?

The edge of the valve will only be 0.5mm closer to the sleeve if you go with the 1mm diameter oversized '97+ ones. Also, going from a 90mm to 90.5mm overbore for the new forged pistons means the valves will really only be 0.25mm closer to the sleeves.:wink: I find it hard to believe it would make that much difference, but what do I know?


How much power were you running when the main caps were discovered to be broken?


He had a CTSC, saw extensive track duty, had a semi-custom aftermarket Tilton fly/clutch setup (which should have been OK though), was it the original crankshaft dampener that potentially degraded but hadn't failed yet?.... Is it obvious I'm trying to rationalize excuses for not doing this to mine? Hopefully I don't regret it.


I do plan on upgrading my rod bolts to the ARP ones. My concern was if the OEM bolts were to stretch and you spin a bearing and/or make the main caps crack.

I didn't realize that there would be other stuff that needs to be replaced in the event of upgrading to ARP bolts.

I figure there are plenty of cars out there making more HP than me with the OEM bolts. The SOS Stage 1 build doesn't say anything about replacing the rod bolts on the 580crank HP build. I will make sure mine are within spec when I take it apart. I expect them to be.. if not :confused:


I'm on the same fence for the billet main caps and it does make sense with regards to balancing the engine properly, which is part of all my engine builds.

SOS only mentions Main cap upgrades in the higher horsepower Stage 2 & 3 rebuilds as an option.

The 580HP SOS FI Stage 1 option here:
http://scienceofspeed.com/products/engine_performance_products/NSX/ScienceofSpeed/custom_engine_program/FI_custom_engine_program/
Specifically lists rotating assembly balance as an option "recommended for racing applications."

I just see that as flawed and a significant contributor to unnecessary main cap stresses. I mean, the pistons are lighter, rod grinding will lighten it, etc. Balancing is typically done to within 1gram. Look at this link for balancing... It's a good read and consistent with other balancing research:
http://www.eddiesvalvegrinding.com/balancing.htm

Dave
 
Dave - when ship out the rotating assembly for balancing are you including everything from the dampener/pulley to the clutch/flywheel/pressureplate installed and balanced as one unit or are you doing each piece individually?

What does something like that cost?

Here's a place that will do it to 0.2gram
<iframe width="560" height="315" src="http://www.youtube.com/embed/x-a68LZpIGo" frameborder="0" allowfullscreen></iframe>
 
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.....I figure there are plenty of cars out there making more HP than me with the OEM bolts. The SOS Stage 1 build doesn't say anything about replacing the rod bolts on the 580crank HP build. I will make sure mine are within spec when I take it apart. I expect them to be.. if not :confused:

The 580HP SOS FI Stage 1 option here:
http://scienceofspeed.com/products/engine_performance_products/NSX/ScienceofSpeed/custom_engine_program/FI_custom_engine_program/
Specifically lists rotating assembly balance as an option "recommended for racing applications."

I just see that as flawed and a significant contributor to unnecessary main cap stresses. I mean, the pistons are lighter, rod grinding will lighten it, etc. Balancing is typically done to within 1gram. Look at this link for balancing... It's a good read and consistent with other balancing research:
http://www.eddiesvalvegrinding.com/balancing.htm

Dave

I'm surprise that balancing isn't offered as a standard build. If I was an builder of performance car engines like the NSX I would have that as a standard service on all of my builds regardless of current or future power goals. This would minimize the potential of stuff shaking and vibrating apart and a very upset customer.
 
Dave - when ship out the rotating assembly for balancing are you including everything from the dampener/pulley to the clutch/flywheel/pressureplate installed and balanced as one unit or are you doing each piece individually?

What does something like that cost?

Here's a place that will do it to 0.2gram
<iframe width="560" height="315" src="http://www.youtube.com/embed/x-a68LZpIGo" frameborder="0" allowfullscreen></iframe>

My quote for a full engine balance from a local engine machine shop is $495.

that's an internal balance and then checked again with the clutch/flywheel.
 
I'm surprise that balancing isn't offered as a standard build. If I was an builder of performance car engines like the NSX I would have that as a standard service on all of my builds regardless of current or future power goals. This would minimize the potential of stuff shaking and vibrating apart and a very upset customer.
The assembly of the whole thing is also just as important.


My quote for a full engine balance from a local engine machine shop is $495.

that's an internal balance and then checked again with the clutch/flywheel.
That's not too bad actually.
 
Dave - when ship out the rotating assembly for balancing are you including everything from the dampener/pulley to the clutch/flywheel/pressureplate?

What does something like that cost?

Here's a place that will do it to 0.2gram

Yeah, if they'll take it. I had asked that question here:
http://nsxprime.com/forum/showthread.php?t=154713

I'm hoping to get the block work and the balance locally, i.e. Columbia, Charlotte (1.5hrs away) or even going to Atlanta (3hrs drive). I still haven't checked out the two recommended machine shops in town....

I've seen quotes for balancing around $750. BUT, that was for aftermarket rods (heavier) and had to have weight added to the counterweights. The tungsten that's added isn't cheap. I'm guessing around $600 for a good balance, similar to BATMANS quote.

BTW, do you guys mind if I add my engine build project to this thread (since the specs and power goals are similar) or should I create a separate BATMANs engine build thread?

Nah, it's cool man. I just ask that you please restrain yourself on GTO and rotary tidbits!

Dave
 
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He had a CTSC, saw extensive track duty, had a semi-custom aftermarket Tilton fly/clutch setup (which should have been OK though), was it the original crankshaft dampener that potentially degraded but hadn't failed yet?.... Is it obvious I'm trying to rationalize excuses for not doing this to mine? Hopefully I don't regret it.

This was my car.

I had a Comptech Supercharger. ~325 RWHP. Nothing special.

Yes I take the car to the track... This is the only place you can really appreciate what the car is capable of.
I am an HPDE instructor. I don't push the car that hard. I don't over rev and such.

The dampener was fine.

Had I been flogging the car or if the dampener was bad I suspect it would have come apart.

I had ScienceofSpeed rebuild my motor. I went for a Low compression 3.2
To quote my wife. "Don't Skimp you get to do this once"
We replace Oil pump, main caps, valves and all hardware, etc... everything Chris recommended.
I am very pleased. The car make 440 RWHP but the torque curve is impressive. It make 300fp at 3000 rpm.

I didn't go for a 3.5 as Chris felt California Smog would be next to impossible.

I also got the ScienceofSpeed Endura Lite Exhaust that sounds nonintoxicating.
 

I'm on the same fence for the billet main caps and it does make sense with regards to balancing the engine properly, which is part of all my engine builds.

SOS only mentions Main cap upgrades in the higher horsepower Stage 2 & 3 rebuilds as an option.

Since my goals are to make whatever power at i bar of boost (14.7 psi) I don't think i will see 580HP that is rated for their stage 1 rebuild.

Look at it this way...
The car stock makes 270 or 290 hp. at the crank.
You are trying to get to 580? That is more than 2x stock power level.

I wanted the car to be reliable. If a main fails it is going to be costly!
Cheep insurance.

Call and Ask Chris what he thinks.
 
To quote my wife. "Don't Skimp you get to do this once"

Sounds like an awesome wife.

I've stooped to convincing mine that twin turbos are necessary components in an engine rebuild :redface: That and stand-alone engine management will increase my fuel economy.

J/K! My wife is pretty cool too.

Dave
 
Sounds like an awesome wife.

I've stooped to convincing mine that twin turbos are necessary components in an engine rebuild :redface: That and stand-alone engine management will increase my fuel economy.

J/K! My wife is pretty cool too.

Dave

I also swapped out my Comptech Supercharger for the Science Of Speed SC and inter-cooler :)

Several years ago for xmas I wanted headers for the car.
She asked how much additional power the car would make.
She than preceded to ask how much additional power a supercharger would make. Than she said "Pick One":smile:

A few years later I got the headers.

None of this will increase your fuel economy. :cool:
 
Look at it this way...
The car stock makes 270 or 290 hp. at the crank.
You are trying to get to 580? That is more than 2x stock power level.

I wanted the car to be reliable. If a main fails it is going to be costly!
Cheep insurance.

Call and Ask Chris what he thinks.

I'm not going for that much power since at 14.7 psi I doubt that our SOS SC can deliver that.
 
Sorry about the crappy images. My Sprint EVO just took a dump for some reason today.

The timing sensor black glue has melted off. Is this typical for forced induction?

Also, my head gasket looked like it was start to leak and one of the head bolts was loose. You can see the oil/carbon in the threads of one of them.

Only one of the piston on one side looks unusually dirty from the top, but there is no evidence of detonation.

Next week he will have the other side pulled.

Don, something else that was brought up to my attention was that I should re-sleeve the block with Darton sleeves. Did you do that?
 

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