Jump to content
SAU Community

Recommended Posts

Ok I did a bit of a search. couldn't find anything. I'm looking at doing some work on my car, has an r32 spec rb25de-t in it.

Looking at putting in an aftermarket ecu and injectors. Wanted to know if anyone had any recommendations on injectors? Brands and size. Currently the car is putting out about 215kw at 18psi on stock injectors, with supporting mods to get it to this stage.

At this stage I don't think I'd want to go past 250-260kw. So would some 550cc or so injectors suffice? If so any good or bad experiences with different brands? Bit of a noob when it comes to injectors.

Link to comment
https://www.sau.com.au/forums/topic/243032-injectors-recommendations/
Share on other sites

Do the R32 RB25DE's use top feed injectors ? Someone did tell me that the top and R33 side feed rails are interchangable with the top feed ones .

I think the Nismo SF 555's or 740's are high resistance saturated injectors so not sure what you'd do with an R32 .

A .

Nismo 555's or 550's (cant remember the size fo RB25's)

They are bigger than you need.

You could get away with GTR 440's adapted to fit and they would be fine. (bit of dicking around)

I believe s15's are 440 and a straight fit, they pop up in a set of 6 from time to time.

After the research i have done a good guide is that whatever horsepower your looking for thats the cc of the injectors you want plus a little more for headroom, the horsepower your after is 350, standards are 370cc so it does not leave you with much head room, next size up would be the S15 440cc, another thing you also need to take into account is once you have 260rwkw will you want more?

Not so long ago i would have been more than happy with the 220rwkw i have now, but things have changed, if you can see this being the case it might be worthwhile going 550cc so you dont have to do another change when your pushing for 300-350rwkw.

Edited by W0rp3D

rule ive heard for minimum injector size is:

divide engine hp (rough figure) by no. of cylinders to get hp per cyl, and you need 5-6 cc fuel per hp

so for you say you want about 400bhp

400hp/6 = 6.667 x 6 = 400cc, plus fudge factor = 500cc injectors

but most of the stuff ive read says its better to go bigger, a good tune should iron out the problem of using oversize injectors, plus it gives u room to make more power with out buying another set of injectors

rule ive heard for minimum injector size is:

divide engine hp (rough figure) by no. of cylinders to get hp per cyl, and you need 5-6 cc fuel per hp

so for you say you want about 400bhp

400hp/6 = 6.667 x 6 = 400cc, plus fudge factor = 500cc injectors

but most of the stuff ive read says its better to go bigger, a good tune should iron out the problem of using oversize injectors, plus it gives u room to make more power with out buying another set of injectors

LOL thats a lot of maths to agree with the theory that if you want 400rwhp that you should go 400cc injectors plus a bit more for head room.

yeh i know, just illustrating the point that its a 6 cyl car, and u need 6 cc per hp

just happend to turn out that way, the rule works for V8 and 4s aswell, then you would be dividing by 8 or 4, then mult by 6

Edited by Kranker
Anybody seen what they can get out of GTR 440cc injs on 4bar base pressure? By my calcs you would be able to see almost 350rwkw.

But gtr injectors are top feed and this application requires side feed.

  • 1 month later...
LOL thats a lot of maths to agree with the theory that if you want 400rwhp that you should go 400cc injectors plus a bit more for head room.

Yes, but your method doesn't take into account the number of cylinders. Which is predominantly fine considering this is a skylines forum, but you get my point.

If you had a 4cylinder engine and you wanted 400rwhp, you'd have to multiply by 1.5 to get an injector size (600cc) plus a bit more for head room.

Krankers method,

400hp/4cyl = 100hp/cyl

100hp/cyl * 6cc/hp = 600cc/cyl (plus fudge factor)

Same sh*t, different smell.

I wouldn't bother trying to retrofit GTR injectors when the S15 injectors are rated the same (if not higher, depends who you talk to) and are sidefeed.

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now


  • Similar Content

  • Latest Posts

    • I don't know for sure, but I'd expect them all to be interchangeable given the diff end and hub end don't move/change between any C34 series. Often Nissan will change part numbers and the aftermarket follows those year ranges; but the original part number change doesn't mean other parts won't fit. The change could be a change in material, internal parts or even just supplier. For example, all the RB gearbox to engine bolts are no longer available and there is a new part number instead. The only change is they went from cadmium plated bolts to zinc plated due to the issues manufacturing with Cadmium. They look different but work the same.
    • One year is a bit concerning. Did you try contacting GSP? It says 5 year warranty on the box if I remember correctly. I'm also running their driveshafts on my S2 Stagea.   You could check the part numbers on Amayama for your year. Here's the link for my 1998 which gives the 39100-23U60 part number. Well, that and 39100-23U70. https://www.amayama.com/en/genuine-catalogs/epc/nissan-japan/stagea/wgnc34/6649-rb25det/trans/391 What does it say for yours?
    • I ordered a GSP Front R/H Axle from here - https://justjap.com/products/gsp-premium-front-driveshaft-r-h-nissan-r32-r33-r34-skyline-gtr-stagea-4wd#description It lasted around a year before one of the boots blew out. I'm lowered, but I have GKTech roll center adjusters. One year seems a little premature. I think I'm going to spend the extra money on an OEM cv axle this time. This website - https://tfaspeed.com/collections/nissan-stagea-wgnc34-x-four-parts/products/nissan-stagea-awc34-260rs-rb26-right-front-axle-drive-assembly Makes it sound like the readily available OEM CV axle will only fit 11.1999 Stagea and up (mine is a 2.1997 S1). The JustJap listing didn't mention any years or anything for the GSP axle. Amayama shows '11.1999' and up as well for that part number. As well as 'plastic boot type'. See attached picture. So I guess my question is, does that axle (39100-23U60) really only fit S2 Stagea? It's the front driver side. If it does, I'd love to buy that instead of rolling the dice on another GSP. I've found that OEM one cheaper here: https://www.partsfornissans.com/oem-parts/nismo-jdm-r32-r33-r34-skyline-gtr-r32-gts4-right-front-axle-3910023u60 and here https://www.nissanparts.cc/oem-parts/nismo-shaft-ft-drive-3910023u60 Just a little confused because the JapSpeed listing for the GSP front driver axle doesn't mention any specific years or anything and it fit my S1 Stagea fine. So will 39100-23U60 fit my S1 Stagea even though technically it says '11.1999' and up? What would have changed? Thanks.  
    • Thanks for the info. The only "Issue" I've had with the shifter is I always found the throw between 4th and 6th gear too close. I'm always worried to shift into 4th accidently and sending my motor to the moon. Adam LZ recently came out with a video and stated Serialnine revised their shifters to correct this and will change all the revised parts for 150$. Strangely enough, I contacted Serialnine right after and they denied it and said it's bullshit. I found that strange as he's a distributer. I'll keep this forum post updated on that saga.
    • Yep that is correct. It allows you to adjust the short throw range from what I can tell
×
×
  • Create New...