what injectors fit top feed rb25 setups?

[chad b.]

I'm just curious as to what injectors to order for a top feed setup for rb25det considering no site has this application listed. Do you just order Honda injectors, or DSM / Evo, or Toyota, or what? I talked with the guys at Fuel Injector Clinic and they had no idea what injector to sell me. I told them my rail was 11mm bore, and the base was factory Nissan, but they didn't know the height. I did a search but couldn't find what I was after.

[StricNyne]

its going to be dependent on your fuel rail, i have 1000cc rc eng low impedence inj and they are 11mm, i know greddy sells a 10.5 and a 11, and on ebay u can get a leaky peice of s*** rail that is useless and leaks. So your options revolve around either the greddy rail with either size and getting the proper inj size 10.5 or 11

[chad b.]

its going to be dependent on your fuel rail, i have 1000cc rc eng low impedence inj and they are 11mm, i know greddy sells a 10.5 and a 11, and on ebay u can get a leaky peice of s*** rail that is useless and leaks. So your options revolve around either the greddy rail with either size and getting the proper inj size 10.5 or 11

Did you read this part: "I told them my rail was 11mm bore, and the base was factory Nissan, but they didn't know the height."

I know what size the bore is, and the base is obviously Nissan. What I don't know is the height, or if any other injectors will work maybe listed for a different application. I did some more digging and found a post where a guy said that 350z injectors were the correct height and bore for an RB25 top feed setup. The only difference I can think of between two different brands of top feed rails for the 25 (besides the bore) would be the height, which is made up by the length of the stand offs supplied by the kit. I don't know why they don't standardize this s*** to take out the guesswork.

[StricNyne]

PL9-1200 is part num for the inj from RC mine is pl9 1000 so i guess the pl9 is the model of inj and its followed by cc

[chad b.]

Awesome, thanks man. I just googled RC SL9 and it seems that is the injector used for Honda B-series motors. So, it may be that Honda B-series injectors will work in an RB25 top feed setup. I'm gonna round up a couple injectors from some local Honda guys and see if they fit.

[chad b.]

PL9-1200 is part num for the inj from RC mine is pl9 1000 so i guess the pl9 is the model of inj and its followed by cc

Which rail are you running?



I got ahold of a Honda B-series injector and tried it. It seemed to work well, except it wasn't tall enough. Simple solution: Chop down the stan-offs. I think I may be onto something. I'm gonna post on HybridZ and see if any of those guys know.

[shanomak]

dont forget the most important part of the injector, and that is rather it is a low impedance or high impedance. this is determined at manufacturing by the engineers and the ecu that controls it will tell it when to fire and how long to fire. injectors are just basic solenoids, that receive commands from the ecu. the impedance is the first step of not letting the magic smoke out of your ecu. go to rc engineering's website and read some of the tutorials on injector basics. very informative.

[chad b.]

LOL, thanks for the info. I know the difference between a low and high impedance injector. Either should work with my setup. I'm running an AEM. I actually decided to buy the JGY fuel rail and their injectors which are an MSD style. They guarantee a leak free fit.

[chad b.]

well just for sh*ts and giggles, I tried a 1G DSM injector, and it fits like a glove. Guess I won't be buying that JGY rail after all. So, for anyone who may buy one, the Godspeed rail for RB25DET can use 1G DSM injectors. I bought this rail against my better judgement, but hey, it matches my cam gears.

[Darius]

chad b - Do you have any pics of the machining inside the fuel rail where the injectors seat? I am curious to see what it looks like on the Godspeed rail. I assume it is an 11mm rail?

[chad b.]

It's 11mm, yea. I haven't taken any pics of the inside of it, but I remember looking in it and it seemed fine to me. I can take a couple pics to post up. I'll try to have them up Friday.

[meet07]

I have the JGY rail with some Delhpi/msd injectors and it fits on the greddy copy cat plenum with no mods. I swapped to low impedence for my build.

[chad b.]

If I could do over, I would buy the JGY for sure. I wanted an HKS rail to match my cam gears, couldn't find one anywhere in stock, so I bought the Godspeed (HKS knockoff). It's the only cheap part on my money pit of a car. lol

[chad b.]

here a pic of the injector bore