hi guys just fitted boost guage to uk spec twin turbo manual 1994. just wondered what boost pressure should be. car is decatted and stainless exaust also have hks super power flow airfilter. according to the guage it's showing 14 psi is this safe and normal ? many thanks steve !!

Safety Boost is 7psi

Standard Boost is 9psi

 

A lot of people on here run 14 psi (and more). Do you have a an aftermarket ECU? You should do or you risk detting.

 

HTH

James

no standard ecu as far as i know. i have not played with the boost at all, is this normal for my mods ? sometimes car misfires at full throttle under load hi-boost. could i have a problem causing hi boost ? could i be hitting boost limiter. why do i need new ecu , to up my fueling ? many thanks steve !!

Aftermarket ECU will have better air/fuel maps for the increased boost.

 

What's probably happened is the previous owner used boost jets (read welding tips in vacuum line) to force the higher boost. Nothing to worry about really. Boost controllers are better as they can control spikes...

 

As for the mis-firing, are you sure it's not detonation. Haven't heard it myself but people say it's like a bag of bolts rattling in your engine :eek:

 

Better wait to see what other, far more experienced people have to say:)

The mis-fire may be lack of fuel or incorrect mix of fuel and air.

 

You may not have an aftermarket ECU, but it may be worth checking what chip you have inside your ECU.

 

Running standard boost on a stock chip that hasn't been remapped is asking for trouble.

 

You can pick an aftermarket JWT or SE chip up from £100.

This may not cure your misfire problem but it will sure make your car safer to run at 14psi.

Just looking through some posts and come acros your message. I currently run standard chip but i am awaiting delivery of my JWT. i have just fitted another boost gauge and it is only reporting about 7psi. the car seems very quick but what is this safety boost? and how do i get it to 9psi before the chip install

 

cheers

 

Bazz (UKJoba)

 

 

Safety Boost is 7psi

Standard Boost is 9psi

 

A lot of people on here run 14 psi (and more). Do you have a an aftermarket ECU? You should do or you risk detting.

 

HTH

James

if the boost is up, it could be the plugs are in poor condition, higher boost levels require a stronger spark.

 

as everyone else has also said - check to see if the ecu is socketed & running an aftermarket chip. 14psi is way too high for standard IMO