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Prospeed rdx injectors & ecu rom tune kit

Don't you also need the dimensions, volume, compression and material parameters of the combustion chamber?

I didn’t think of that but yeah, it sounds like that should definitely be important, too.

For what it’s worth, the data I have for 3.0 liter NSXs is:
  • Bore: 90 mm
  • Stroke: 78 mm
  • Swept volume (displacement): 496.2 cc’s per cylinder
  • Compression ratio: 10.2:1
  • Volume of combustion chamber above piston at TDC: 53.9 cc’s
  • Included angle between intake and exhaust valves: 62°
In the pic you can see the vectoring of the holes and they go right and left... This should give us close to a 25 degree to 30 degrees.

In the video I posted earlier on the first page if you look carefully as the injector slows down you can see it is separated.

You’re right. Very cool. Looking at the nozzles in the picture, freeze framing the video, and measuring the angles, it looks like the RDX injectors have about a 25° cone width, a “split stream” pattern, and no “bend”. Looking at the dimensions of an NSX intake port and the mounting position of the injector, it looks like the RDX injector should fog the fuel at the two intake valves while wetting the walls as little as possible. I'm no expert but from what I’ve read about injectors, that sounds pretty much ideal. And another thing that sounds good about the RDX injectors – OEM Honda reliability and if ever required, parts availability from your local Honda dealer. OK, I’m sold. Now I just need someone to tune a chip for me since my engine has ported cylinder heads, an increased compression ratio, high-lift camshafts, I’m planning on adjusting my cam gears slightly away from the OEM specs, etc. Brian, are you coming to Europe any time soon?
 
I will talk to someone. I work at Bosch Anderson, but I deal with TCU, ECU, ESP, and ABS. does someone have the official intake/cylinder dimensions and angles? and stock fuel injector stats vs. the new one. Ill just give them everything and get an opinion.
Thank you very much. The stock 3.0 injectors flow 240 cc’s per minute and are the pintle type. The RDXs flow 410 cc's per minute. Do you need to know the angle the fuel hits the intake valves at in an NSX or the angle of the injectors relative to the axis of the cylinder?
 
Thank you very much. The stock 3.0 injectors flow 240 cc’s per minute and are the pintle type. The RDXs flow 410 cc's per minute. Do you need to know the angle the fuel hits the intake valves at in an NSX or the angle of the injectors relative to the axis of the cylinder?

Yeah, I will probably need that info. The guy that I am going to ask is the guy over the LS3 line. The other guys would be worrying about economy, lol. I sent him an email seeing when he has time to meet and help me understand the calculations. Ill stay posted
 
OK, the first picture in post #89 (from JGE) is of an NSX intake port and I found a good cross sectional drawing of the engine in case that helps visualize the shapes and angles:



If you click on the thumbnail, you can get to a high resolution version of the drawing.

Based on that:
  • The fuel hits the back of intake valves at an angle of 65°
  • The axis of the injectors is 55° off the axis of the cylinders
Thanks again for speaking with your colleague and I look forward to hearing what you find out.
 
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Based on fastrax_turbo and 96cxt's results, I would expect keeping the VVIS plate but gutting the butterflies to kill mid-range TQ with little gains up top, and getting rid of the VVIS plate altogether to show bigger gains up top (for an NA application). Both users had their intake manifolds ported as well.

As to increased fuel pressure, Bisi & Tony Palo both expect a "few" HP. What "few" translates to will be seen soon.
 
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I didn’t think of that but yeah, it sounds like that should definitely be important, too.

For what it’s worth, the data I have for 3.0 liter NSXs is:
  • Bore: 90 mm
  • Stroke: 78 mm
  • Swept volume (displacement): 496.2 cc’s per cylinder
  • Compression ratio: 10.2:1
  • Volume of combustion chamber above piston at TDC: 53.9 cc’s
  • Included angle between intake and exhaust valves: 62°


You’re right. Very cool. Looking at the nozzles in the picture, freeze framing the video, and measuring the angles, it looks like the RDX injectors have about a 25° cone width, a “split stream” pattern, and no “bend”. Looking at the dimensions of an NSX intake port and the mounting position of the injector, it looks like the RDX injector should fog the fuel at the two intake valves while wetting the walls as little as possible. I'm no expert but from what I’ve read about injectors, that sounds pretty much ideal. And another thing that sounds good about the RDX injectors – OEM Honda reliability and if ever required, parts availability from your local Honda dealer. OK, I’m sold. Now I just need someone to tune a chip for me since my engine has ported cylinder heads, an increased compression ratio, high-lift camshafts, I’m planning on adjusting my cam gears slightly away from the OEM specs, etc. Brian, are you coming to Europe any time soon?

I would love to go snowboarding in the Alps! But I don't plan to go to Europe for at least another couple of years. I would love to tune your car with the mods that you have.

This is pretty exciting. Definitely subscribing to this thread for future updates!

There will be more exciting news coming soon! =)
 
I would love to go snowboarding in the Alps! But I don't plan to go to Europe for at least another couple of years. I would love to tune your car with the mods that you have.
Asides from cost and install differences can you help me understand what's the difference in the tuning you do with the chip vs. what can be done with an FIC? thx!
 
Asides from cost and install differences can you help me understand what's the difference in the tuning you do with the chip vs. what can be done with an FIC? thx!

The FIC has pretty much everything we can do as far as tuning fuel except for timing advancement... It can only retard timing. It also has boost support in case you decide to go FI in the future. With our own tuning we can advance timing, control more parameters and have the ability to shut down certain sensors as well.
 
so I had to try this...

i had Downforce AIS, ITG Foam filter, CT Headers, Pride V2 Exhaust, ATI harmonic damper, and Prospeed Chip... and about 250lbs of weight reduction. Adding the RDX Injectors made a BIG difference.

the power gains are insane. just so much torque at cruising RPM's now. i echo the remarks about this feeling like a larger engine... the torque is really surprising. throws my head back into my seat. i would have to say it feels like an F430 now. and considering i had 21 year old injectors on there of the finest 80's technology with almost 139,000 miles on it... i feel much better having replaced them with the latest and greatest.

great mod, a no brainer... Brian is a great guy, as well, so there is no reason not to do this. he also has a bunch of them in stock and ready to go.
 
The FIC has pretty much everything we can do as far as tuning fuel except for timing advancement... It can only retard timing. It also has boost support in case you decide to go FI in the future. With our own tuning we can advance timing, control more parameters and have the ability to shut down certain sensors as well.


Anyone try this with a 3.2L and FIC yet?
 
Anyone try this with a 3.2L and FIC yet?
If part of the gain made on the 3.0L's is due to upping the timing then, according to Brian, the FIC only gives the option to retard, not to advance.

So the question is.. was there any timing manipulations done or does the chip modifications strictly alter the fuel delivery?
 
HBui,

Did you dyno test as well?

Congrats on your new found torque. Amazing, isn't it?

unfortunately, no before dyno to show the differences, but i will be dyno tuning next week with Brian.

yeah the torque is crazy. the biggest difference really is driving around town, so i think this mod would even appeal to the regular joe not interested in racing.
 
unfortunately, no before dyno to show the differences, but i will be dyno tuning next week with Brian.

yeah the torque is crazy. the biggest difference really is driving around town, so i think this mod would even appeal to the regular joe not interested in racing.

Hey its Scott, the guy helping Brian out last night, I'm glad you like the mod! The difference is definitely noticable :smile: I might have to swing by when you visit the dyno to watch you make some good power lol.
 
so I had to try this...

i had Downforce AIS, ITG Foam filter, CT Headers, Pride V2 Exhaust, ATI harmonic damper, and Prospeed Chip... and about 250lbs of weight reduction. Adding the RDX Injectors made a BIG difference.

the power gains are insane. just so much torque at cruising RPM's now. i echo the remarks about this feeling like a larger engine... the torque is really surprising. throws my head back into my seat. i would have to say it feels like an F430 now. and considering i had 21 year old injectors on there of the finest 80's technology with almost 139,000 miles on it... i feel much better having replaced them with the latest and greatest.

great mod, a no brainer... Brian is a great guy, as well, so there is no reason not to do this. he also has a bunch of them in stock and ready to go.

Glad you like it! It really is an amazing mod! :)
 
If part of the gain made on the 3.0L's is due to upping the timing then, according to Brian, the FIC only gives the option to retard, not to advance.

So the question is.. was there any timing manipulations done or does the chip modifications strictly alter the fuel delivery?

RYU,

The timing was adjusted however it only attributed to about 1-4whp in certain areas... On L_RAO's car he already produced his huge torque gain around 4k Before timing adjustments were made and same with frumpybumps car.
 
So if we wanted to do this with a VTEC controller instead of FIC or AEM for OBDII, and not make any timing adjustments, it would still be a huge improvement- correct? Just thinking about options out loud for feedback.
 
Yes.

If you look at my original thread, we made monster gains down low (before Prospeed was able to get the VTEC maps worked out). I drove the car for about 40 days without going into VTEC.

The 2nd time we dyno'd, advancing the timing was good for 2 peak wHP.
 
Do these kits keep the proper safety buffer on the fuel to air ratio? I like extra power but I want to do it safely. Also I have plans to go turbo down the road any adverse effects in doing so. Will this work on a CTSC engine?
 
Do these kits keep the proper safety buffer on the fuel to air ratio? I like extra power but I want to do it safely. Also I have plans to go turbo down the road any adverse effects in doing so. Will this work on a CTSC engine?

My car is running safer AFR's now with the injectors than before when I just had a full exhaust. These were the results from my car's before and after dyno runs. You can see that the AFRs before were super high, almost touching 16:1 at one point. Now they are much better sitting right around 13:1. I like having the peace of mind knowing that its running at a safer level than before.

Also, Brian (Prospeed) was saying that this should be a good mod for the CTSC guys since I guess the kits use the stock 240cc injectors but they do some fuel pressure increase or whatnot, I'm not completely sure. I'm sure Brian can chime in and explain it better.

Here is Frumpbumps recent dyno charts!

His car has 175K miles on it. I had Bisi scale the AFR how most dynojet scale their AFR graphs.

-Blue line is with Pride exhaust, headers, test pipes and Factory ECU.
-Orange line is with Pride exhaust, headers, test pipes, RDX Injectors and Prospeed RDX Spec Program.

His car also responded well to the RDX injectors. He picked up 26ft lbs of torque at around 4000rpm and about 20whp. Up top he pick up a little over 10whp. Keep in mind his car has a lot of miles on it. Not bad at all! You can see how lean the NSX runs with a stock ecu, injectors and common bolt ons!

JacquelineNSXPwr1.jpg


JacquelineNSXAFR1.jpg
 
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It is pretty clear that the tune that I'm driving around with is much safer than the OEM tune. I'm well under 14.0, whereas I was over 15.0 in stock tune.

FI is a different game - depending on how much boost you'll be running the RDX injectors might not be big enough. Prospeed does sell a turbo kit I believe so he should be able to better answer your questions.
 
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