KRIS.
How do you know it is safe?

Stef.

 

Hi KRIS,
I tried a bleed valve and had one fitted to previous car,problem on car now was-peak boost 17/18 dropping back to 16 and when car was full and in high gear or under load it would hit overboost cut out,turning boost down gave 16 odd peak holding 14 which was no better than standard really so i took it off.it made the boost behave like a wastegate only pressure control-high peak dropping off.
The hose i had it in may have been too long so i will shorten it to the length of the black piece under soleniod and try it in there.

What about putting a bleed valve just before the map sensor so it sees boost lower than it really is just to get a couple of psi,anyone tried this.

where is yours fitted KRIS.
cheers Pete

 

Hi there,
A question for someone understanding how the boost is controlled.

AS i know it the map sensor converts psi into volts then supplies the ecu this info which sends some of this to the wastegate solenoid and regulates boost to around 14 psi (99 car).
how can we make the boost settle at 16 psi,is it a case of fitting a different resistor somewhere or altering the software?
I dont want to use a bleed valve and the evc seems a bit pricey just to get 2psi.

thanks Pete

 

Why dont you want to use a bleed valve ? I have had one fitted to my 98 with no probs at all AND it is safe. My cars peaks at just over 16 psi and holds this until near the red line where it drops back to std

k

[This message has been edited by KRIS (edited 04 November 2000).]

 

I have mine fitted in the pipe just before the boost solenoid. I have not changed the pipe just cut into it. I know it is safe because the car still sees the boost level. If it didnt then the overboost would not cut in. My 98 model overboost cuts in at 16.5 psi or thereabouts and i can maintain aprox 16psi. I have not been greedy and am happy with the little extra. If you want more then i am told it means taking out the overboost safe gurads....erm no thanks.
k

 

Kris
Thats all fine, however have you had the fueling checked on the rollers to ensure its sufficient for the increased boost?

If not you could be running lean....


I tried a bleed valve whilst on the rollers and the resultant curve would have been undrivable. This was 17psi peak 16psi held.

I wouldnt do it again, unless mapped in.

Regards

Richie

 

I couldnt get anywhere near 17psi as the overboost would cut in. I only have the extra couple and as far as I`m concerned and have read etc its doing no damage and I`m happy with that....No doubt some people will panic and want to spend thousands on mapping and all that.
k

 

Fair enough, just pointing out that you dont know the car is safe at all unless you get it dynod. Just because the ECU detects the increased boost it does not mean its safe. Your running more boost and without extra fueling to compensate.
I thought you said you were getting 16 PSI, seems close to 17 to me.
Some cars are fine and owners have run bleed valves or EBCs for years without a single glitch. If it was me, Id at least check it on a rolling road to ensure I wasnt running lean and risk detonation, but maybe I value my pistons too much

Rich


[This message has been edited by RichieC (edited 08 November 2000).]