After taking my car to a track for a bit of a blast, when I was coming down the straight, foot to the floor, the car hit about 140mph and then lurched and lost power. I lifted off and the dump valve released. On the next lap I managed to get it back to the same speed but a bit more gentally and that didnt happen. I was wondering what could cause this?? A mate of mine who also has a scoob suggested it overboosted?? if so how do you go about curing this problem?? Its on a MY98 Sti4, mods are HKS Hiper, HKS Downpipe, HKS SQV and K&N cone filter

[Edited by Graham Beal - 8/7/2002 7:09:35 PM]

Probably hit the boost cut ... amazing how much more boost these cars can peak on the track, despite being very hot they always boost higher.

One way of compensating is to open the restrictor up (adjacent to the boost control solenoid in the top pipe) but you will then lose a bit during normal use.

Bob

[Edited by Bob Rawle - 8/7/2002 11:04:57 PM]

In the same vein a restrictor valve can come in handy to enlarge the restriction as much as you need when on track.

A Dawes actually worked best of all boost control methods (ECU, EBC, bleed valve, needle valve, fuel cut lifter and different restrictor etc) on track I reckon, but that was on a UK car.

Thanks for your help, Im glad to see that its nothing major!!! :)