Rb25 Boost/fuel Problems

[si3.bang!]

Hi ive been reading stuff on this site for a while and now need some of the great knowledge that is out there.

i have a rb25det in s13 have just replaced the cast exhaust manifold with stainless item. first problem is the piping had to be redone and i think i made it too big and laggy 2.5" to intercooler and 3" to throttle. second problem the wastegate actuator was hitting the rocker cover so i removed it and welded it up. yet to fit the external gate.

when driving the car before it was only at 7psi but it pulled strong through the whole rev range and was almost completely lag free in any part of the rev range.

now it is slow to build up boost * strange due to there being no wastegate??? and when it does it is quite weak (feeling) although the gauge can go up to 1.5bar maybe 2bar.

in some points the fuel cut or whatever is happening comes in at different boost speeds and rpms?

what do i need to adress?

[burnsie]

mine sorta has the same problem in my ceffy. so if anyone has any idea please help

[SilverCal]

So let me get this right..you have removed the wastegate actuator and welded up the flap in the exhaust housing?? and you have not fitted an external gate??..this will mean that there is no way it can control the boost! it will just keep rising!! and you say it is reaching 2 bar?...do you know what detonation sounds like?? it would feel weak as there will not be enough fuel to match the air if you are only running stock stuff!

[paulr33]

1) unlimited boost will cause engine failure

2) unlimited boost will cause turbocharger failure

3) unlimited boost will break other stuff

4) stop loading the engine up while its running as "unlimited boost"

5) baby the car around until you fix it properly - dont load it up

6) get a real ecu

7) stop doing ghetto mods and being stupid