Fresh rb swap making little to no power.

[sviellvoicae]

Hey guys just looking for a little insight on why my rb is lacking power. Its an rb25det into a 91 s13. Here is the best way I can explain what its doing.

When I get on it, it seems to get louder but kinda falls on its face. First gear seems to be ok power wise but 2nd and so on is terrible. I have been in a 240 with a stock rb20 and that was easily faster than this. I know something is wrong cause I got smoked by a single cam ka. Im not looking for huge performance right now as it is an all stock setup other than a z32 maf, apex afc, exahust, intercooler. Nothing done to the motor and Im at stock boost as well. Any info will be a huge help. Thanks in advance. I know its really little info but ask questions and I will try to answer as best I can. O not sure if it matters but the car drives great runs great idles great just under boost seems to faceplant. Thanks again.

[sci2000tech]

Could be a slipping clutch?

[sviellvoicae]

Its not he clutch for sure. I know what that feels like and how the car reacts. I guess its more of a bad hesitation. When It boosts the car gets louded like it wants to go but something is holding it back.

[Yellow4g63]

check the codes in the ecu. could be a bad CAS, or knock sensors.

[rb25det250sx]

i wouldnt think the coil packs would make it get louder my any means, but check them while your at it. couldnt hurt.

[yotik]

Humbly speaking:

Does it build full boost? My Rb "fell on its face" because of loose upper intake mani, ic clamps. It would boost to about 9psi then couldnt hold anymore. Rechecked clamps and mani=problem solfffed...seriously man it could be a lot of stuff- what seems outta place? Boost? Throttle response? Hesitation?

[Joe]

what spark plugs are you using at what gap?
whats your timing set at?

[USMCgetsome]

i agree could be a boost leak or to be honest it sounds like a maf or fuel pump problem. I had all those same issues and one by one they started to get fixed. First it was the boost leak then my maf started to go out then my fuel pump slowly stopped working in a course of 6 months. They were all very tough to diagnose although doing all 3 of those brought my setup back to life and fun to drive again.

[ralphsdiorama]

Make sure your CAS is positioned correctly. Sounds like your timing may be a bit retarded. no pun intended.

[virus77]

Boost leak or timing is way off or tps is screwed up... I would say the first two are more likely.