car is an s2 erst, it has been tuned by power engineering, i bought it to work in and it has been mucked about with. cars running a t34 and boosts to just over 1 bar.

now the problem im having is not in 1st and 2nd its fine, 3rd 4th and 5th however it will only make it to 4000rpm before bogging down and not making power, the turbo spins up but just wont make any more power. anyone got any solutions?

 

When did power's last set it up ? Does it just hit the limiter like it's overboosting ? Or just not accelerate at all ? Any smoke from the back of it ??

 

Could be the metering unit

 

quite a few years ago by now, and yeah seems to spool up to quickly, so probably overboosting. no smoke. car is also running a dumpvalve

 

take it to a tuner mate

 

i would say it over boosting when i put a 31 actuator on mine it was sort of like that.
if you have a bleed valve take it off and try a standerd amel valve on there if it runs better is probibly a over boosting problem

 

Take it to Power's or Torque Of The Devil near by to get checked out

 

sounds like surge(running to the right of theturbo airflow curve) , i have the same problem in 4/5th at over 0.5 bar
never had it with my sidedraughts , so im going to change the throttle to a larger unit and build a side feed plenum

if you have a boost guage fitted , it will show a rapid left to right cycling?

problem is time. your turbo in higher gears has more time to spool up and so builds up very high boost pressures at very low air flow rates
and runs into surge

its a bastard to understand as very few people understand this , spent weeks on the net to get to this conclusion

to get around this , you may eed to either change the cold side of your turbo and go smaller or unrestrict the flow capability or your engine with headwork , high lift cam , match porting etc