Prospeed RDX/Injector kit

Joined
22 July 2014
Messages
54
Location
Sunnyvale, CA
I was wondering if anyone was running this particular kit from ProSpeed:

http://www.prospeedpower.com/nsx_rdx_injectors_intall.html

My friend gave me his set up before parting out his NSX but forgot one of the pieces on the kit which I am trying to locate. I haven't been able to get in touch with ProSpeed so any help would be appreciated. I currently have the items pictured in the ProSpeed link above. I also have an already modded ECU (my friend's ECU + the prospeed chip so I'll be able to keep my own untouched). I and was told by one Prime member that it sounded like I was missing some sort of bypass piece that helps control the idle. Any help would be greatly appreciated, thank you for reading =)
 
You probably need these 2 items -> 8 Phenolic Fuel Rail spacers and 1 Injector Resistor Bypass Plug. I am waiting on mine from a fellow prime member who sold me his kit. Cost is around $30.
 
I paid Prospeed for this two items for jtrikakis 3 weeks ago and I havent recieved it yet. Initially Brian said he has them so I sent the payment then after two weeks i followed up this time he said his guy has it. I made the paypal payment thru family and friends so that he wont be charge fees. I'll wait until Friday then I'll just write a review.
 
The rail spacers will be needed as these injectors are shorter and will need them to make sure you don't leak raw fuel into the top of the manifold. As to the bypass resistor, When I bought my car with the RDX injectors already installed, I did not have the bypass for the fuel pressure and the car idled just fine. I will bypass mine when I go FI in the future. For just a mild improvement in performance, you may not even need it. I had the Stage 2 chip for what it's worth.
 
Could be but I thought it was to bypass the fuel pump resistor that uses low flow at low rpm's and it jumps up to full feed at higher rpm's.
 
You probably need these 2 items -> 8 Phenolic Fuel Rail spacers and 1 Injector Resistor Bypass Plug. I am waiting on mine from a fellow prime member who sold me his kit. Cost is around $30.

I have the spacers, it was the injector resistor bypass plug i am missing. Is there a part number on that thing? I've tried for months to get in touch with those guys but haven't been able to get any help =(
 
I feel stupid for not looking this up but at the same time elated because I can finally order this damn thing and install the kit. Thank you so much!!!

your welcome, i had the same problem but worse which ended up being a disaster, we had the car scheduled and setup for 2-3 hours DYNO time to do a before and after on the Dyno install without moving the car which meant doing the install on the dyno without moving it so there would be no variables.

While the car was strapped to the dyno we finished the install and the car would not run properly and that's when we double checked the instructions and noticed the bypass plug was missing from the used kit I bought from member Valhalla (whom was apathetic and passive regarding my troubles, that's another disappointing story, in 9 years of buying/selling used on prime this was the first member I've had a problem with). The car had to be moved around the shop for a few days since the ECU chip was already changed/installed as well as the injectors so reversing the install would mean removing the ECU again to swap the chip and injectors. Luckily after few phone calls someone one from a nearby honda tuning shop had a spare plug from another Honda and custom made one and brought it to the shop. Ended up costing a few hundred dollars of time and effort for the shop and custom plug and a wasted a few more hundred dollars in the failed before/after dyno test attempt to have no variables. Later we figured we could get it from SOS but that would have taken just as long to ship/receive.

Over all word of caution, if your buying a used prospeed RDX kit make sure you get the bypass plus, it seems easy to miss since it is hardly visible and plugged into the female end of the resistor box wire coming from next to the side engine compartment fan.
A second thing to keep in mind is that the original RDX kit price includes the cost of ECU socket itself and install service, so if your buying used you will have to pay someone to do it.

Some pics from the dyno install at STP motorsports which is very trusted Dyno in the area that some of the best known tuners in south Florida use this DYNO regularly, its known to give reasonable numbers, it does not really read high nor low so 281rwhp was great. FWIW The local dynodynamics which is known to read lower estimated 275, so I guess it's somewhere between them two. for comparison a newer Porsche caymen that leads the continental challange race series professionally was there being tuned and only put down 263rwhp on this dynojet and that was on a full standalone Motec ecu, so I was very proud of this 23 year old Honda putter putting down 281rwhp on oem ecu.


 
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Your situation sounds like it was a total nightmare! I'll take some pictures of all my parts. My friend actually gave me his entire ECU with the chip installed already as his car went off to be parted out after a nasty accident that wasn't his fault =(. I have the injectors and I'll make sure I have the spacers, I believe I do - Gorgeous car by the way =)

your welcome, i had the same problem but worse which ended up being a disaster, we had the car scheduled and setup for 2-3 hours DYNO time to do a before and after on the Dyno install without moving the car which meant doing the install on the dyno without moving it so there would be no variables.

While the car was strapped to the dyno we finished the install and the car would not run properly and that's when we double checked the instructions and noticed the bypass plug was missing from the used kit I bought from member Valhalla (whom was apathetic and passive regarding my troubles, that's another disappointing story, in 9 years of buying/selling used on prime this was the first member I've had a problem with). The car had to be moved around the shop for a few days since the ECU chip was already changed/installed as well as the injectors so reversing the install would mean removing the ECU again to swap the chip and injectors. Luckily after few phone calls someone one from a nearby honda tuning shop had a spare plug from another Honda and custom made one and brought it to the shop. Ended up costing a few hundred dollars of time and effort for the shop and custom plug and a wasted a few more hundred dollars in the failed before/after dyno test attempt to have no variables. Later we figured we could get it from SOS but that would have taken just as long to ship/receive.

Over all word of caution, if your buying a used prospeed RDX kit make sure you get the bypass plus, it seems easy to miss since it is hardly visible and plugged into the female end of the resistor box wire coming from next to the side engine compartment fan.
A second thing to keep in mind is that the original RDX kit price includes the cost of ECU socket itself and install service, so if your buying used you will have to pay someone to do it.

Some pics from the dyno install at STP motorsports which is very trusted Dyno in the area that some of the best known tuners in south Florida use this DYNO regularly, its known to give reasonable numbers, it does not really read high nor low so 281rwhp was great. FWIW The local dynodynamics which is known to read lower estimated 275, so I guess it's somewhere between them two. for comparison a newer Porsche caymen that leads the continental challange race series professionally was there being tuned and only put down 263rwhp on this dynojet and that was on a full standalone Motec ecu, so I was very proud of this 23 year old Honda putter putting down 281rwhp on oem ecu.


 
While the car was strapped to the dyno we finished the install and the car would not run properly and that's when we double checked the instructions and noticed the bypass plug was missing from the used kit I bought from member Valhalla (whom was apathetic and passive regarding my troubles, that's another disappointing story, in 9 years of buying/selling used on prime this was the first member I've had a problem with).

Are you sure you want to go down this road again Patricio? I advertised a used kit complete with pictures. You wanted it and I made a concession as to price and even mailed it to you on my dime. You received it, didn't like what you received and then asked if there were any more parts. I replied that my mechanic (Ramon at Niguel Motors) was in Hawaii for the weekend and would get with him at first chance to see if there were indeed anymore parts. You then threaten me with a PayPal claim while still asking for my help. It's not normal to slap someone while asking for their help. You then made a claim that same day on PayPal. You stated in the complaint that I did not send you the item, so you looked like a fool when I provided the tracking number inclusive of the insurance I placed on the parcel that you received.

I have been here for years also and helped anyone I could with their NSX. Check out my thread on EPS repair, engine wiring harness trouble codes, etc. I am a respected member of the NSX SoCal group and on the committee to host NSXPO this fall. If you are going to publish stories about me, get your facts straight. I don't feel that I need to publish your PM's to back this up. I would appreciate if you retract the above quotes in the your post and I will delete this one. Your call.
 
Wow.. you are complete liar.... and i have it all in writing if you would further want me to post everything...

for one the pay pal claim was only denied because i paid you as a gift and pay pal does not have any buyer protection for that.. i have that in writing...

My claim which was immediatley after you stated you wpuld not refund me anything and made that very clear... the claim clearley stated that you sent me an incomplete kit. Never did i claim i did not recieve the item at all. Thats all in writing... wow. Your full of it.

You post had a picture of items in a box and stated that it was the prospeed rdx kit. But it was not the "kit". The "kit" comes with the injector bypass plug.. your package of parts did not include the plug as you admit, yet you act as if you have no responsibility for sending me an incomplete kit...

you state you made "concessions" and sent it on your "dime" things get sold with or without shipping all the time i was not aware the $15 it proably cost you to ship would be refered to as on you "dime" i would imagine this term to be saved for a relevant cost or favor and last time i checked you did me nothing as favor.... $500 for an RDX kit that is 750 new minus the chip socket and minus installation soldering of the chip socket and missing the same bypass plug this gentelman on this thread also went through grief to find is hardley a deal at all. All i asked was for a refund of the $80 of the custom rush plug that was made as a favor in exchange for the hundreds of dollars and days of complications due to your neglidgence which i understand was not intentional, but is no excuse.

You sent me an incomplete kit.. period... and your a liar...

i can post screenshots of all the crap you just claimed which is a complete lie.

I am not arguing over $80... which is a complete waste of my time... but your a piece of work and everyone should know.

Post whatever you want. I have my facts straight...i've been on and off this forum for almost 10 years and owned several NSX's. And have sold used turbo kits and superchargers.. big dollar stuff. Never a complaint. You already admitted sendig me an incomplete kit and act as if you have something on me... you cant even admit a small wrongdoing when its in your face and prefer to point the finger at me... lol...

Are you sure you want to go down this road again Patricio? I advertised a used kit complete with pictures. You wanted it and I made a concession as to price and even mailed it to you on my dime. You received it, didn't like what you received and then asked if there were any more parts. I replied that my mechanic (Ramon at Niguel Motors) was in Hawaii for the weekend and would get with him at first chance to see if there were indeed anymore parts. You then threaten me with a PayPal claim while still asking for my help. It's not normal to slap someone while asking for their help. You then made a claim that same day on PayPal. You stated in the complaint that I did not send you the item, so you looked like a fool when I provided the tracking number inclusive of the insurance I placed on the parcel that you received.

I have been here for years also and helped anyone I could with their NSX. Check out my thread on EPS repair, engine wiring harness trouble codes, etc. I am a respected member of the NSX SoCal group and on the committee to host NSXPO this fall. If you are going to publish stories about me, get your facts straight. I don't feel that I need to publish your PM's to back this up. I would appreciate if you retract the above quotes in the your post and I will delete this one. Your call.
 
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your welcome, i had the same problem but worse which ended up being a disaster, we had the car scheduled and setup for 2-3 hours DYNO time to do a before and after on the Dyno install without moving the car which meant doing the install on the dyno without moving it so there would be no variables.

While the car was strapped to the dyno we finished the install and the car would not run properly and that's when we double checked the instructions and noticed the bypass plug was missing from the used kit I bought from member Valhalla (whom was apathetic and passive regarding my troubles, that's another disappointing story, in 9 years of buying/selling used on prime this was the first member I've had a problem with). The car had to be moved around the shop for a few days since the ECU chip was already changed/installed as well as the injectors so reversing the install would mean removing the ECU again to swap the chip and injectors. Luckily after few phone calls someone one from a nearby honda tuning shop had a spare plug from another Honda and custom made one and brought it to the shop. Ended up costing a few hundred dollars of time and effort for the shop and custom plug and a wasted a few more hundred dollars in the failed before/after dyno test attempt to have no variables. Later we figured we could get it from SOS but that would have taken just as long to ship/receive.

Over all word of caution, if your buying a used prospeed RDX kit make sure you get the bypass plus, it seems easy to miss since it is hardly visible and plugged into the female end of the resistor box wire coming from next to the side engine compartment fan.
A second thing to keep in mind is that the original RDX kit price includes the cost of ECU socket itself and install service, so if your buying used you will have to pay someone to do it.

Some pics from the dyno install at STP motorsports which is very trusted Dyno in the area that some of the best known tuners in south Florida use this DYNO regularly, its known to give reasonable numbers, it does not really read high nor low so 281rwhp was great. FWIW The local dynodynamics which is known to read lower estimated 275, so I guess it's somewhere between them two. for comparison a newer Porsche caymen that leads the continental challange race series professionally was there being tuned and only put down 263rwhp on this dynojet and that was on a full standalone Motec ecu, so I was very proud of this 23 year old Honda putter putting down 281rwhp on oem ecu.

What other mods do you have? That seems pretty high for the Prospeed kit.
 
Well so much for the retraction. I guess we agree to disagree. The matter is closed.


Sure.... You can "Close the matter"

- - - Updated - - -

What other mods do you have? That seems pretty high for the Prospeed kit.

FWIW this RDX kit was only a test out of curiosity to see how much power I can document N/A prior to installing the turbo in few weeks. My car already dynoe'd 279-280 recently with the mods listed below running an autothority chip that is no longer produced..... The RDX kit unfortunately only gained 1-2whp and 1-2 TQ and we think its underperforming since its a stage 2 RDX tune which is likley insufficient for the mods especially the cat delete and likley the tune in not optimal optimal. I'm sure their is more HP there and its a shame we cant tune the RDX chip.

The next test invloves the AEM Infinity I just received last week from SOS for the turbo kit going in a few weeks, but will first install and tune the infinity EMS for the N/A setup with RDX to see what the max RWHP can be extracted with all the bolt-ons out of curiosity before going turbo. Likely just blowing money here, but I just need to know :) My goal is to see what the best 1/4 time I can pull N/A at 2500lbs with A/C and full interior. I'm convinced a lightweight NSX is capable of accelerating on par with stock weight CTSC car. Which if its even close in acceleration it would mean the 700lbs lighter car would outperform the heavier CTSC car on the track once deceleration, cornering, break fade, and heat soak is introduced into the equation. 3100lbs / 350rwhp = 8.85 power to weight VS 2500lbs / 285rwhp = 8.77 power to weight


DC headers (on car when I bought it)

I have done quite a few tests on various items while on the dyno without removing the car
The ones that I confirmed conservatively say dyno:

The Super damper ATI lower MOI crank pulley gained 1-3whp on dyno
RSR Oil additive gained 1-3whp dyno
Uni air filter gained 2-4whp dyno
A custom 3" BPI velocity stack mounted into OEM airbox entrance mouth fed by the down force intake snorkel gained 2-4whp dyno
Taitec GT009 cat delete exhaust (already had exhaust but added additional 8rwhp on dyno more over old exhaust)
Lightweight forged 15lbs motegi tracklites gained 2-4 whp dyno on 21lb slightly worn 25" diamater 255-40-17. (but had 22lbs 19" wheels with 25.5" diameter 275-30-19 23lb worn tires before. This has much more complex Moment of inertia explanation to be saved for another thread someday, as I do not want to argue physics on a car site.) :)
Lighweight SOS flywheel and clutch -15lbs saving quite a bit of inertia (don't know how much rwhp this releases but it may free up 1-3rwhp estimate)
Royal purple synthetic oil for past 9 years that I've owned the car
4.23 short gears
Polished heads with SOS upgraded titanium retainers & valve springs (3-5rwhp estimated)


- - - Updated - - -
 
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Sure.... You can "Close the matter"

- - - Updated - - -



FWIW this RDX kit was only a test out of curiosity to see how much power I can document N/A prior to installing the turbo in few weeks. My car already dynoe'd 279-280 recently with the mods listed below running an autothority chip that is no longer produced..... The RDX kit unfortunately only gained 1-2whp and 1-2 TQ and we think its underperforming since its a stage 2 RDX tune which is likley insufficient for the mods especially the cat delete and likley the tune in not optimal optimal. I'm sure their is more HP there and its a shame we cant tune the RDX chip.

The next test invloves the AEM Infinity I just received last week from SOS for the turbo kit going in a few weeks, but will first install and tune the infinity EMS for the N/A setup with RDX to see what the max RWHP can be extracted with all the bolt-ons out of curiosity before going turbo. Likely just blowing money here, but I just need to know :) My goal is to see what the best 1/4 time I can pull N/A at 2500lbs with A/C and full interior. I'm convinced a lightweight NSX is capable of accelerating on par with stock weight CTSC car. Which if its even close in acceleration it would mean the 700lbs lighter car would outperform the heavier CTSC car on the track once deceleration, cornering, break fade, and heat soak is introduced into the equation. 3100lbs / 350rwhp = 8.85 power to weight VS 2500lbs / 285rwhp = 8.77 power to weight


DC headers (on car when I bought it)

I have done quite a few tests on various items while on the dyno without removing the car
The ones that I confirmed conservatively say dyno:

The Super damper ATI lower MOI crank pulley gained 1-3whp on dyno
RSR Oil additive gained 1-3whp dyno
Uni air filter gained 2-4whp dyno
A custom 3" BPI velocity stack mounted into OEM airbox entrance mouth fed by the down force intake snorkel gained 2-4whp dyno
Taitec GT009 cat delete exhaust (already had exhaust but added additional 8rwhp on dyno more over old exhaust)
Lightweight forged 15lbs motegi tracklites gained 2-4 whp dyno on 21lb slightly worn 25" diamater 255-40-17. (but had 22lbs 19" wheels with 25.5" diameter 275-30-19 23lb worn tires before. This has much more complex Moment of inertia explanation to be saved for another thread someday, as I do not want to argue physics on a car site.) :)
Lighweight SOS flywheel and clutch -15lbs saving quite a bit of inertia (don't know how much rwhp this releases but it may free up 1-3rwhp estimate)
Royal purple synthetic oil for past 9 years that I've owned the car
4.23 short gears
Polished heads with SOS upgraded titanium retainers & valve springs (3-5rwhp estimated)


- - - Updated - - -

a lot of detailed information.

by the way, thanks for the bar.:biggrin:
 
FWIW this RDX kit was only a test out of curiosity to see how much power I can document N/A prior to installing the turbo in few weeks. My car already dynoe'd 279-280 recently with the mods listed below running an autothority chip that is no longer produced..... The RDX kit unfortunately only gained 1-2whp and 1-2 TQ and we think its underperforming since its a stage 2 RDX tune which is likley insufficient for the mods especially the cat delete and likley the tune in not optimal optimal. I'm sure their is more HP there and its a shame we cant tune the RDX chip.

The next test invloves the AEM Infinity I just received last week from SOS for the turbo kit going in a few weeks, but will first install and tune the infinity EMS for the N/A setup with RDX to see what the max RWHP can be extracted with all the bolt-ons out of curiosity before going turbo. Likely just blowing money here, but I just need to know :) My goal is to see what the best 1/4 time I can pull N/A at 2500lbs with A/C and full interior. I'm convinced a lightweight NSX is capable of accelerating on par with stock weight CTSC car. Which if its even close in acceleration it would mean the 700lbs lighter car would outperform the heavier CTSC car on the track once deceleration, cornering, break fade, and heat soak is introduced into the equation. 3100lbs / 350rwhp = 8.85 power to weight VS 2500lbs / 285rwhp = 8.77 power to weight


DC headers (on car when I bought it)

I have done quite a few tests on various items while on the dyno without removing the car
The ones that I confirmed conservatively say dyno:

The Super damper ATI lower MOI crank pulley gained 1-3whp on dyno
RSR Oil additive gained 1-3whp dyno
Uni air filter gained 2-4whp dyno
A custom 3" BPI velocity stack mounted into OEM airbox entrance mouth fed by the down force intake snorkel gained 2-4whp dyno
Taitec GT009 cat delete exhaust (already had exhaust but added additional 8rwhp on dyno more over old exhaust)
Lightweight forged 15lbs motegi tracklites gained 2-4 whp dyno on 21lb slightly worn 25" diamater 255-40-17. (but had 22lbs 19" wheels with 25.5" diameter 275-30-19 23lb worn tires before. This has much more complex Moment of inertia explanation to be saved for another thread someday, as I do not want to argue physics on a car site.) :)
Lighweight SOS flywheel and clutch -15lbs saving quite a bit of inertia (don't know how much rwhp this releases but it may free up 1-3rwhp estimate)
Royal purple synthetic oil for past 9 years that I've owned the car
4.23 short gears
Polished heads with SOS upgraded titanium retainers & valve springs (3-5rwhp estimated)

That would explain it! I thought I was getting really cheated with the mod! LOL
 
The next test involves the AEM Infinity I just received last week from SOS for the turbo kit going in a few weeks, but will first install and tune the infinity EMS for the N/A setup with RDX to see what the max RWHP can be extracted with all the bolt-ons out of curiosity before going turbo.

I for one am very curious to see what happens.

Prospeed had indicated here that a custom AEM tune would "pick up even more hp".

Please keep us all updated.
 
View attachment 126733View attachment 126734View attachment 126735View attachment 126736

My concern is my buddy included 4 of the original fuel rail spacers. He did give me a box of copper ones with the same size (would the different material matter here if the sizes are the same?)
I have 6Xinjectors
The bypass plug
A ready to go ECU with the tune and chip already installed from my friend's NSX.

FWIW... I cant imagine why any correct size spacer would not work. But I'm no expert


I for one am very curious to see what happens.

Prospeed had indicated here that a custom AEM tune would "pick up even more hp".

Please keep us all updated.


Will do... I just have to know as well.
 
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