Stock RB25 fuel pressure?

Post by **Joe** » Fri Sep 19, 2003 9:07 pm

I was "forced" to get a nismo adjustable FPR because my clip didnt come with a fpr, so what is fuel pressure of the stock rb25 set at?:ylsuper

Post by **vududoc** » Fri Sep 19, 2003 9:07 pm

32psi idle 43 no vacuum

Post by **Joe** » Fri Sep 19, 2003 9:07 pm

that seems kinda low to me, can anyone else verify?

Post by **vududoc** » Fri Sep 19, 2003 9:07 pm

thats what i thought but i tuned to it as my pump was dropping hella gas. other pressure that i got was 36 at idle from SDU forums

Post by **hashiriya13** » Fri Sep 19, 2003 9:07 pm

I do believe it is 43 but could be wronge.

Post by **Joe** » Fri Sep 19, 2003 9:07 pm

lol am i gonna have to get a stock fpr to test?

Post by **vududoc** » Fri Sep 19, 2003 9:07 pm

nah go to SDU theres a string there

Post by **Nismo_Freak** » Fri Sep 19, 2003 9:07 pm

Standard FP on most Nissan engines is around 32-36 at idle.

Post by **JonPowell** » Fri Sep 19, 2003 9:07 pm

32 idle, 43 vacuum is correct. I spoke to one of the techs at RB Motoring and it is the correct pressure. The funny thing is that the FPR from your KA will work also. All Nissan motors run the same pressure. I switched mine and NO PROBLEMS, except for the blown head, but that is the correct pressure.

Post by **vududoc** » Fri Sep 19, 2003 9:07 pm

Muhahahaha i was right :P lol

Post by **Joe** » Fri Sep 19, 2003 9:07 pm

damnit! oh well im glad i got a FPR. good self-tuning aid with a EGT gauge.

Post by **vududoc** » Fri Sep 19, 2003 9:07 pm

i ran into that snag with my fpr...but people couldnt even tell me when to get one for the rb20. now im just looking for an incar FP gauge.

Post by **Nismo_Freak** » Fri Sep 19, 2003 9:07 pm

JonPowell wrote:32 idle, 43 vacuum is correct. I spoke to one of the techs at RB Motoring and it is the correct pressure. The funny thing is that the FPR from your KA will work also. All Nissan motors run the same pressure. I switched mine and NO PROBLEMS, except for the blown head, but that is the correct pressure.

Stock KA idle pressure is 34 psi... they are not all the same.

Post by **Joe** » Fri Sep 19, 2003 9:07 pm

vududoc wrote:i ran into that snag with my fpr...but people couldnt even tell me when to get one for the rb20. now im just looking for an incar FP gauge.

be prepared to spend some $

i know jegs sells one, around 200$

Defi has one also

im sure there are 100 others but i KNOW of those 2.

Post by **wcbjr** » Fri Sep 19, 2003 9:07 pm

How much HP will the stock KA FPR handle?

Post by **Nismo_Freak** » Fri Sep 19, 2003 9:07 pm

FPR's aren't rated on their HP ability.. they are rated on their pressure ability. Since it's not adjustable you can't raise or lower the pressure, you must increase the injector size/duty/pulsewidth to raise the amount of fuel present in the mixture.

Post by **wcbjr** » Fri Sep 19, 2003 9:07 pm

So I can run the KA FPR and RX7 440cc injectors and still have proper fuel pressure for up to 400crank hp?

Post by **Nismo_Freak** » Fri Sep 19, 2003 9:07 pm

Yes... but I'd get the FD's 550cc injectors and have them cleaned and reconditioned. If your not aware of this, you should know that RX7's are notorious for having clogged up injectors.

Post by **wcbjr** » Fri Sep 19, 2003 9:07 pm

Any reasoning for the clogged injectors? Sounds kinda strange.

I think 440's will be enough for 400crank, and they are ~65 for a set of 4. Servicing for ~25 a piece and that comes to 165 for 4 fully functioning injectors.

Post by **PROJECTRB240SX** » Fri Sep 19, 2003 9:07 pm

BUY THE 55OCC INJECTORS FROM NAPA OR AUTOZONE. THOSE COME ON THE 89-91 CORRECT?

Post by **wcbjr** » Fri Sep 19, 2003 9:07 pm

Yeah, the 550's for an RB20 are from an 1989-1991 Mazda RX7 Turbo-II.

Denso 195500-2020

The 440's are 195500-2010 from a non-turbo model.

Post by **PROJECTRB240SX** » Fri Sep 19, 2003 9:07 pm

Post by **wcbjr** » Fri Sep 19, 2003 9:07 pm

Those are 460cc on the non-turbo, not 440.

Post by **PROJECTRB240SX** » Fri Sep 19, 2003 9:07 pm

WHO DID YOU GET YOUR HEAD GASKET AND STUDS FROM?

Post by **PROJECTRB240SX** » Fri Sep 19, 2003 9:07 pm

BTW WE ARE GOING TO USE COPPER, GOOD CRUSH RATE AND SUPER HIGH TOLERENCES TO PRESSURE.

Post by **wcbjr** » Fri Sep 19, 2003 9:07 pm

I got mine from Paeco. I sent in an old gasket and bolt.

$250 for the gasket/sealant, about $225 for studs and nuts/washers.

Post by **PROJECTRB240SX** » Fri Sep 19, 2003 9:07 pm

ARE YOU SATISFIED WITH THEIR PRODUCTS?

Post by **wcbjr** » Fri Sep 19, 2003 9:07 pm

Don't know yet, they are sitting in my apartment office. They closed early yesterday. I will try to get pics up asap. I'll also take some pics of that eBay'ed SSAutoChrome tubular manifold while I'm at it. I promised those a while back but have not had a camera to take pics with.

Post by **PROJECTRB240SX** » Fri Sep 19, 2003 9:07 pm

OK, I'D LIKE TO SEE THEIR GENERAL DESIGN. TO SEE WHAT I SHOULD DO.

Post by **vududoc** » Fri Sep 19, 2003 9:07 pm

wcbjrhey can you tell me more about that manifold...i contacted them directly and hadnt a clue.......and i know i saw that manifold. Details on manufacturer would be nice as im looking to buy them in bulk

Stock RB25 fuel pressure?

Stock RB25 fuel pressure?

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