jools1010

HI all, went for my first proper spin in the car today after buying it have have noticed big lurch only in 4th gear??

when the car hits 80ish it happens 100ish and 110 all happens without the hiss of the dump valve? it feels like you taken your foot off the gas..

I then tried it in 3rd and 5th and it didn't happen

Any idea will be of great help

Cheers

Jools


P.s. test was on be local air field...

scooby546

iTrader: (1)

Sounds like boost cut maybe, when the ECU cuts boost when it passes a preset level to protect the engine. Can feel like hitting a brick wall, more likely to happen in higher gears as the engine is under more load and gets more boost as a result.

Hope that helps a bit
Cheers

Pete

jools1010

Ok, I've read alot about overboost so what the best solution to overcome the problem.

Whats the restrictor pin?? this is in a rubber pipe so why do people drill it? what would happen if you replaced the pipe with one without a pin?

Cheers

Jools

scooby546

iTrader: (1)

Depends which model year etc, I'm not 100% sure but in some I've heard that drilling the brass restrictor pill out a little lowers the maximum boost - so in theory if you remove it then you might drop the boost right off, which would stop it overboosting for sure, but you just want to drop it a little. What's the boost maxing out at just now, and what was it running before, if you know?