rb25 no power

SON240sx Automotive
1

hi guys i need some help on this one. i recently put forged internals in my rb25. before the rebuild the car made 330rwhp on 12 psi. now after the rebuild it revs up all the way with no hiccups or misfires but it feels like it only has the power of a ka24de. my boost gauge shows im building boost. my A/F gauge seems to be reading ok. my timing is right. anyone got any ideas on what i can look at? im stumped…

i have an rb25 s2 with gt2871r on stock exhaust manifold. isis intake manifold and tomei cams

2

Tell us more about the car, better yet if you have a video of the car running and driving that would make it much easier. It could be as simple as a boost leak if its or a few if its pullin like a KA hahahah

3

The car has an hks blowoff, manual boost controller and gtr intercooler. It was tuned on a rb20 ecu. I check the codes on it.only code is a knock sensor code but iv heard that’s a common code on older nissans. I looked for boost leaks and I can’t find any although I may have missed one. Also when the car is cold it bogs down alittle but once warm runs a lot better. I will try to get a video of it driving soon as I can

4

prob boost leak, did you put it on the dyno and see what its actually putting out?

5

cap your bov, my old bov had a bad spring and wouldnt close all the way when it was cold, but when it warmed up from the engine heat it worked fine

6

I have not had a chance to put it on a dyno yet. I will definetly check the bov again though. I’m going nuts trying to find boost leaks now lol

7

Ok bov is good. I did another boost leak test an found out my new gt2871r turbo is leaking out of the compressor housing. Fml!!! Is there a large oring between the compressor and turbo? Anyone ever have this issue? Can I seal it somehow? Thanks for the help guys!

8

LOL of course theres a seal between the comp. housing and the CHRA!! LOL

giant o ring.

9

Ok fixed the compressor housing. Found another leak at the shaft on my throttle (q45) I tried taking it apart an putting in a oring did not help at all. Anyone got any ideas I googled it and its very common? This leak is pretty big I’m hoping the car will pull harder when fixed

10

are you using the “freddy” intake manifold? you can use a tiny bit of rtv and seal it but dont tighten the bolts all the way until its slightly dry

11

I’m using a isis intake. Its not leaking from the bolts its leaking from the throttle plate shaft were it comes out to meet the throttle linkage. I’m gonna try a various of oring sizes today to see if I can come up with something