• ***AVOID MARKETPLACE SCAMS!!***

    Scammers are using compromised Prime member accounts to pose as a trusted seller in the marketplace. Before you enter into a deal with any seller, follow these tips to keep yourself safe. If you encounter one of these scammers, please report them immediately and we will lock their account.

    Caveat Emptor!

Prospeed rdx injectors & ecu rom tune kit

Brian,

I'm interested in this as well. This might fix my other issue that I've been having... (if you recall, I PM'ed you about it a few weeks back).

Let me know how to proceed...I have one of your earliest Prospeed chips.

Thanks,
- Zishan
 
Brian,

I'm interested in this as well. This might fix my other issue that I've been having... (if you recall, I PM'ed you about it a few weeks back).

Let me know how to proceed...I have one of your earliest Prospeed chips.

Thanks,
- Zishan

Hows it going? Yes, It sounds it could possibly solve your issues! People need to realize that over 20 years injectors do get clogged or start leaking. That's a long time and if you're going to clean them you might as well upgrade to a superior injector. You got PM.
 
For hardcore NA guys, it seems like the Prospeed RDX injector kit +
ITB's would be a match made in heaven!!!!!
 
I purchased the RDX injectors from Prospeed last Friday. After being at Bisimoto and witnessing L_RAO dyno his car and having seen in person what the injectors could do, I told Prospeed to get me a set ASAP! The car feels so amazing now! It feels much more gutsy, especially starting down low in the rpm range whereas before I'd really only feel the kick once the motor was already wound up. The car feels quicker now especially since the power isn't just up top but also in the midrange where I find myself rolling around in most of the time. Its definitely quicker to get up and go now as opposed to before.

I picked up the injectors from Prospeed since I'm local to him and he installed the injectors at his house on the spot. It took about 30 minutes and did not seem difficult at all. He installed the injectors and reflashed my ecu all at once and the car fires right up and idles like stock. I've done one tank's worth of fuel so far and i averaged 24 mpg, which isn't bad especially since I've been using the loud pedal more liberally just to feel the difference in power.

I'm going to visit the dyno this week to see if my car can put down numbers that are similar to what L_RAO achieved. I've baselined my car ('91 with 175k mi) with headers, test pipes, and a Pride V1 exhaust on the same dyno that L_RAO did his testing on and I put down 246whp and 187 lb/ft, so I'm very close to him on the baseline measurements. Hopefully the dyno visit can reaffirm what my butt dyno has told me so far. I definitely have high hopes for the outcome.

I threw in a couple of pictures I managed to snap during the installation process, its a pretty straightforward install and the injectors look kinda cool since they're blue. You can just catch a glimpse of them underneath the covers when everything is put together. Also notice the difference in size between the OEM injectors and the RDX injectors they are much more compact and lighter. Another nice thing is that the connectors on the RDX are much easier to install and remove, unlike the stock connectors that have the metal clip on them. There is also a picture of the bypass plug located next to the fan that never turns on.

Thanks frumpybumps! I still can't get over your screen name lol... Looking forward to seeing how your car does on the dyno!
 
More dyno results please! thanks

I'm naturally skeptical at this point since only one dyno sheet has been provided and the AFR dips in that look sketchy (It's not scaling of the graph).

Since I don't know what timing or fueling adjustments have been made i'm going out on a limb and hoping for consistent/better results with other cars.
 
More dyno results please! thanks

I'm naturally skeptical at this point since only one dyno sheet has been provided and the AFR dips in that look sketchy (It's not scaling of the graph).

Since I don't know what timing or fueling adjustments have been made i'm going out on a limb and hoping for consistent/better results with other cars.

There will be more dyno sheets give it time for people to test it out on their own cars. There's nothing sketchy about the results. The AFR's are safer than stock and produce results that are impressive. The car idles well with the larger injectors and so far 3 customers have noticed increased power. Also I would love better results as well but injectors and tuning can only produce so much power... did you want 50 ft lbs of torque instead? :) Give it time... In the next week or two there will be more NSX owners with this amazing mod.
 
There will be more dyno sheets give it time for people to test it out on their own cars. There's nothing sketchy about the results. The AFR's are safer than stock and produce results that are impressive. The car idles well with the larger injectors and so far 3 customers have noticed increased power. Also I would love better results as well but injectors and tuning can only produce so much power... did you want 50 ft lbs of torque instead? :) Give it time... In the next week or two there will be more NSX owners with this amazing mod.
No offense intended. I'm just reading the dyno and a few other folks picked up on it too. I'm hoping for the best with this mod. Dyno results will speak for themselves.

As with what happened to the SOS ITBs what one car sees on the dyno may not be the same outcome on another.

Thanks for everyone's efforts.
 
kookoo: the only problem is that ITBs require a standalone EMS.

EZ: our results were pretty clear and our testing procedures were controlled. My only regret was that I didn't do the fuel pressure testing that day as well.

The flaw in the ITB test was that ITBs AND EMS were added at the same time. That test should have been (1) EMS, tuned to the max, then (2) ITBs, tuned to the max.
 
the kit definitely sounds interesting!

I'd like to see how it compares to a 100% stock (un-modified) NSX AFR curve on the dyno as well, just to see if it's close and not simply a leaner mapping that creates the power gains...

I would love power gains that maintain the safety tolerances of OEM engineering.
 
very impressive Brian, i might have to pay you another visit soon. lol.

Sounds Good! =)

No offense intended. I'm just reading the dyno and a few other folks picked up on it too. I'm hoping for the best with this mod. Dyno results will speak for themselves.

As with what happened to the SOS ITBs what one car sees on the dyno may not be the same outcome on another.

Thanks for everyone's efforts.

None taken... I know people will always be skeptical. People doubted L_RAO's efforts when he began this project as well. Every car is different... some will make more power than others. That's how it's always been. Yes, you will see more dyno graphs out there and like I say give it time.

For hardcore NA guys, it seems like the Prospeed RDX injector kit +
ITB's would be a match made in heaven!!!!!

Yes, it would be but ITB's right now require a standalone EMS.... but give it time =)

kookoo: the only problem is that ITBs require a standalone EMS.

Yes, for now!

EZ: our results were pretty clear and our testing procedures were controlled. My only regret was that I didn't do the fuel pressure testing that day as well.

The flaw in the ITB test was that ITBs AND EMS were added at the same time. That test should have been (1) EMS, tuned to the max, then (2) ITBs, tuned to the max.

You're correct! I really wish we got that FPR on your car! AEM is currently on backorder for them too! =(

the kit definitely sounds interesting!

I'd like to see how it compares to a 100% stock (un-modified) NSX AFR curve on the dyno as well, just to see if it's close and not simply a leaner mapping that creates the power gains...

I would love power gains that maintain the safety tolerances of OEM engineering.

This would be great however most NSX owners have either an exhaust or headers or a both. I could do a tune just for a 100% stock NSX but not sure if anyone would just leave their car that way =)

Also there seems to be a misconception with leaner conditions and more horsepower.... That is not true at all! Lean conditions in the 14.5 to 16 or higher is dangerous at WOT. Part throttle is a different story... Our part throttle map is dialed in and runs right about stoich(14.7). Lean conditions cause detonation and loss of power because the factory knock sensor will try to retard timing.... For NA typically 13.0 to 13.7 is the universal standard for the most power. If you look at our dyno graph you can see an NSX with stock injectors and stock ecu with just headers run lean! It wants more fuel. The AFR the NSX runs now is safer in every way.
 
I'll certainly be ordering this kit soon, how does this effect emissions?
 
I'll certainly be ordering this kit soon, how does this effect emissions?

Emissions shouldn't be a problem. We've compensated for the extra fuel and the car runs great through all rpm's. The original stage 3 rom passed smog with no problems so this tune should do just as well. Someone will test it on a smog dyno soon. =)
 
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
 
This along with bolt-ons seems like just about the best thing you can do for a mild NA setup.

So it is safe to say this is basically a "reflash" tune designed around the RDX injectors and bolt-ons?

Everyone knows the sos itb's is the best bolt on. Why do you think no one ever says anything bad about the cost and gain per dollar spent. Everyone always says... I want.

ITB's are far more cost effective, way more reliable, and the gains are through the roof for 8,9,lets call it 10k dollars.

This is just a stupid injector swap that if they don’t sell thousands of these kits... we all need to rethink whether or not we should just sell our NSX's as we are no longer worthy or smart enough to own one.

Hats off dudes.. I questioned it when Loc brought it to my attention.. I bow down to you guys.

Taking advancements outside the carbon fiber airBOX that still needs to be designed for the killer ITB set up and raising the bar for all of us to continue to think of the possibilities...

I’m sure Danny did this before the RDX was a car.. but way to design a cost effective modernization to our already super car.

Peace,
 
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!

I've always thought this was a neat idea. It is amazing to see the difference at 4k RPM's. This also happens to be where the fuel pump gets a boost. Did you play around with different fuel rail pressures to see if you can get more of a gain?

I'm sorry, but otherwise, the 10-15WHP gain throughout the rest of the RPM band can simply be attributed to a better tune for the vehicle mods and location.

I'm still very curious how this will work at higher pressures!

Dave
 
Everyone knows the sos itb's is the best bolt on. Why do you think no one ever says anything bad about the cost and gain per dollar spent. Everyone always says... I want.

ITB's are far more cost effective, way more reliable, and the gains are through the roof for 8,9,lets call it 10k dollars.

This is just a stupid injector swap that if they don’t sell thousands of these kits... we all need to rethink whether or not we should just sell our NSX's as we are no longer worthy or smart enough to own one.

Hats off dudes.. I questioned it when Loc brought it to my attention.. I bow down to you guys.

Taking advancements outside the carbon fiber airBOX that still needs to be designed for the killer ITB set up and raising the bar for all of us to continue to think of the possibilities...

I’m sure Danny did this before the RDX was a car.. but way to design a cost effective modernization to our already super car.

Peace,

Sorry I used the word best if that is what you are getting at. I am new...

I wouldn't really consider itb's a bolt on affair but hey, what part doesn't bolt on?:rolleyes:
 
This might have to be my next mod. Great bang for the buck

Thanks! I totally agree! Headers typically on an NA1 will give you about 10 to 15hp tops. Exhaust systems as well. This is just amazing especially down low and mid range where we are normally at everyday!

Is the delta for the 20whp gain at 4k? How many miles did the original base dyno car have on it?

The base dyno and after had over 175k on it. At 4k there is 20whp! That is real!

This along with bolt-ons seems like just about the best thing you can do for a mild NA setup.

So it is safe to say this is basically a "reflash" tune designed around the RDX injectors and bolt-ons?

I agree... and yes it is pretty much a reflash designed around the RDX injectors and bolt-ons... very similar to the Hondata reflash for the RDX or Civic Si.

Everyone knows the sos itb's is the best bolt on. Why do you think no one ever says anything bad about the cost and gain per dollar spent. Everyone always says... I want.

ITB's are far more cost effective, way more reliable, and the gains are through the roof for 8,9,lets call it 10k dollars.

This is just a stupid injector swap that if they don’t sell thousands of these kits... we all need to rethink whether or not we should just sell our NSX's as we are no longer worthy or smart enough to own one.

Hats off dudes.. I questioned it when Loc brought it to my attention.. I bow down to you guys.

Taking advancements outside the carbon fiber airBOX that still needs to be designed for the killer ITB set up and raising the bar for all of us to continue to think of the possibilities...

I’m sure Danny did this before the RDX was a car.. but way to design a cost effective modernization to our already super car.

Peace,

Ross you always crack me up! Honestly I was someone skeptical in the beginning as well and I give props to L_RAO for doing it! I'm impressed with the low and mid range the most. The NSX is much happier not having to run lean =) CEM... cost effective modernization is exactly what this is =)

Very interested. Question. My ECU was chipped by SOS before I bought the car. Are you able to re chip it or can you reprogram the one on there?

I would need your ecu to reprogram the chip. I could reprogram the existing one or send you one that is ready to go and you just need to replace it.

I've always thought this was a neat idea. It is amazing to see the difference at 4k RPM's. This also happens to be where the fuel pump gets a boost. Did you play around with different fuel rail pressures to see if you can get more of a gain?

I'm sorry, but otherwise, the 10-15WHP gain throughout the rest of the RPM band can simply be attributed to a better tune for the vehicle mods and location.

I'm still very curious how this will work at higher pressures!

Dave

I agree that some of the extra tuning up top attributes to the 10-15whp but that just reaffirms to everyone why we need to have an ecu rom upgrade when we upgrade with bolt ons. If anyone had a stroker kit we could do a custom tune with the RDX injectors. I am extremely impressed with the low to mid range as it is the most important for every day driving and spirited mountain runs. =)

Sorry I used the word best if that is what you are getting at. I am new...

I wouldn't really consider itb's a bolt on affair but hey, what part doesn't bolt on?:rolleyes:

I didn't get it at first glance either! I'm not sure about other mods but I am sure this is a good bang for the buck mod!
 
More modern injectors definitely sound promising. On witchhunter.com (a company that cleans and flow tests injectors), they describe various kinds of injector spray patterns:
  • Wide or narrow spray
  • Single stream or “V”-shaped (separate streams to spray into the individual intake ports of multi-valve engines)
  • Straight or angled (so that the stream sprays toward the back of the intake valve even if the injector isn’t pointed straight at it)
And then any combination of the above, adjusting the angles so that the fuel sprays down the backs of the intake valves given the geometry of the cylinder head and how far away the injectors are installed. Another specification along which injectors vary is the electrical resistance or impedance they present to the engine management system.

If the OEM NSX injectors are simply wide, single stream injectors, that shouldn’t be too hard to improve upon. If the OEM NSX injectors have a “V”-shaped spray pattern and/or spray the stream at an angle to hit the intake valves dead-on, it might be more tricky.

Do you know what spray pattern and impedance the OEM injectors have and how the RDX injectors compare in those two areas?
 
More modern injectors definitely sound promising. On witchhunter.com (a company that cleans and flow tests injectors), they describe various kinds of injector spray patterns:
  • Wide or narrow spray
  • Single stream or “V”-shaped (separate streams to spray into the individual intake ports of multi-valve engines)
  • Straight or angled (so that the stream sprays toward the back of the intake valve even if the injector isn’t pointed straight at it)
And then any combination of the above, adjusting the angles so that the fuel sprays down the backs of the intake valves given the geometry of the cylinder head and how far away the injectors are installed. Another specification along which injectors vary is the electrical resistance or impedance they present to the engine management system.

If the OEM NSX injectors are simply wide, single stream injectors, that shouldn’t be too hard to improve upon. If the OEM NSX injectors have a “V”-shaped spray pattern and/or spray the stream at an angle to hit the intake valves dead-on, it might be more tricky.

Do you know what spray pattern and impedance the OEM injectors have and how the RDX injectors compare in those two areas?

Hi Greenberet,

I always like it when you chime in! It's always productive... =) Here is a lil more info and hopefully this can explain why the RDX injector idles well and makes more horsepower and torque over the factory injector and in theory should improve emissions and gas mileage! The pictures below belong to witch doctor and motoiq. Thanks!


OEM HONDA INJECTOR

The oem 240cc Honda injector is a peak and hold low impedance injector using a pintle style head.

"Pictured below is the earliest and the most common tapered pintle design that was used in most injector designs in the 70's thru the 80's. The pintle is tapered with a mushroom shaped tip causing the spray to diverge as it leaves the injector tip.

Note: the pintle cap was removed for this picture."- witchhunter.com

Std%20pintle%20Bosch.jpg
Std%20pintle%20spray.jpg




OEM RDX INJECTOR

The OEM RDX 410cc injector is a high impedance saturated injector.

"Due to the more demanding emission requirements thru the years, the injectors makers started putting more smaller holes to help atomize the fuel especially when the engine is first started. This one has four holes." -witchhunter.com

The RDX injector uses 12 holes that are vectored to help with atomization.

4%20hole%20Bosch.jpg
4%20hole%20spray.jpg


Here is the head of the RDX injector It's their newest DENSO injector pic belongs to motoiq.com the injector pictured is from a nissan but its identical.

17-L.jpg


Here is more info on the RDX injectors direct from the DENSO website

"One of the true innovators in electronic fuel injection technology, DENSO introduced the 12-hole injector in 1999. Its breakthrough design reduced fuel droplet size to 65 microns, providing superior atomization for improved engine efficiency. In 2002, DENSO followed with its UC injector, reducing droplet size even further, down to 50 microns – around one-half the width of a human hair. That same world-class engineering expertise goes into DENSO's entire line of First Time Fit® fuel injectors. Added-value materials and innovative features like welded seals allow DENSO injectors to meet the most rigorous emissions requirements in the world, including those for Super Ultra Low Emissions Vehicles (SULEV) and Partial Zero Emissions Vehicles (PZEV). A DENSO fuel injector is a precision instrument – they're that accurate.

While the electronic fuel injection systems in today's cars are incredibly sophisticated and can adapt to a wide range of conditions, their real-world performance often comes down to the accuracy and consistency of the injectors themselves. Each injector must deliver precisely the right quantity of fuel at exactly the right instant, thousands of times per minute, or performance, economy, and engine smoothness will suffer. The top parts distributors, retailers, and technicians won't settle for second-best on these crucial components. That's why they select DENSO First Time Fit© fuel injectors.

FEATURES

Premium internal components and welded-seal construction
DENSO fuel injector technology boasts the highest dynamic range
Calibrated impedance assures full system compatibility

BENEFITS

Maintains new-car smoothness and drivability
First Time Fit® saves valuable shop time
DENSO's injectors finer fuel spray significantly reduces exhaust emissions

"The injector atomizes a predetermined amount of fuel and delivers the fuel spray toward the intake valve based on signals from the Engine ECU. DENSO's injector generates finer fuel spray particles, significantly reducing the amount of hydrocarbon in the exhaust gas."

The RDX uses the newer UC injector
"UC 12 holes Fuel injection opening area gradually increases."

injector2.jpg


The image above from motoiq shows the vectored holes.

"Benefits and Features

Small fuel spray particles
The fuel flow to the fuel injection opening in the injector is improved – reducing the particle size of fuel spray (C60, UC).
The fuel injection opening area gradually increases, resulting in further reduced particle size of fuel spray (UC).
High responsiveness
Industry-leading fuel injection responsiveness due to improved magnetic circuit and lighter-weight valve.
Small size
Sealing by welding results in smaller injector size. (C60, UC)."

Heres an inside pic of the C60. This injector didn't have the vectored holes but is essentially the same injector besides the regular holes.

injector3.jpg
injector.jpg
 
Last edited:
I am currently looking for a 95+ NSX owner wanting to do this mod. We will need to dyno test your car. We are now offering the RDX install kit with an AEM FIC. If you're in the So Cal area and interested in having your car tuned for the RDX injectors please PM me for price and details. Thanks!
 
Back
Top