hi everyone, i just picked up an 89 turbo2 and was wondering if anyone had a picture or coud tell me where the stock boost gauge is suppose to reading at when on boost, in my car it only ever reaches the second line above the zero, which is about half of what i think its suppose to be reading, thanks for the help. its completely stock s5 and has 71,000 miles

 

Welcome to the club.

I will ask one of the members more familiar with the 89-91 Turbos to answer.

 

thanks, ill post a pick when i get a chance

 

Hi. Welcome to the club.


While I don't have the exact answer to your question I do have some tid bits you might find helpful.

The stock boost level for an S5 (1989-1991) turbo is about 7.5psi.

Unfortunately, the stock boost gauge is usually not very accurate and it is often recommended to purchase an aftermarket boost gauge. They can be had for a few bucks online and are easy to install but they will give you an accurate reading of your boost levels which is what your looking for.

Be sure to check out the FAQ's on here and FC3Spro.com.

Good luck man.

 

A little more than halfway between 0 and 45 is the highest I've seen it go on an unmodified S5 TII. As said above, the stock gauge is impossible to get an accurate reading and might want to get a more accurate gauge to see exactly how much you are boosting. However, I would say that the stock gauge is a pretty good indication of whether or not you are boosting, just the actual amount is difficult.

You may have a small boost leak somewhere in your system. I'm kind of in the same boat as you are right now. Mine used to deflect about 60-70% above 0 between 0 and 45. Now it doesn't go above 0, and the power is gone.

 

i wanna thank everybody for their imput, after tinkering with the car i found that the hose < stock intercooler piping> that connects the turbo to the recirculating valve pipe was loose. i tightened and i a diffrence, the boost gauge moves up one more notch. i know that the stock boost gauge is inaccurate, but im only using it as a refference. my concern now is that if its been loose for a long time is there a realistic chance that ive been overboosting/overreving the turbo? if so what would be the consequences?