Hi, Im wondering what psi would be considered a "good" motor. If there was 100psi on all faces, is that good? What would a new motor produce? What is the number that means the engine is getting pretty tired, and should be rebuilt before an apex chucks out? Thanks

Wondering about an s5 turbo motor

 

100 is wonderful on all faces, a tired motor is usualy around 75-80. a rebuilt motor after the break in period should have around 115-100 in most case

 

The Jspec that im buying supposedly has no less than 100psi per face. Most people say that a Jspec should always be rebuilt before use. With 100psi, do you all think this should be rebuilt? Im getting poor, and a rebuild would really delay my car getting a motor. Let me know what you all think. Thx

 

well I would first test the compression yourself, Ive told over the phone that motors had good this, good that - its ****** bull...check it out yourself first...

If you indeed have ~ 100psi on all faces, then - yeah - run it

The reason that people say you'll need to rebuild it is because in MOST cases you do, I have had to in every case......but there are good ones out there - you just need to verify it yourself.

 

Thats what I planned on doing. I was going to hook the starter up to a battery, hold the throttle body open and check what its got... Now how should I go about getting a good compression reading? Should I do it dry, or put a little lube in the plug holes? Thanks

 

Yup and also to port that biatch!!

Personally if I were to buy a jspec, regardless of claimed condition, I would rebuild and port it.

 

Is porting it really worth all the time/money to tear it down? How much HP increase from a basic streetport?

 

Well if your running short on time and money then tearing it down just to port it probably won't be a good idea for you. But a large majority of the folks who have rebuilt their engines or dropped in a jspec without porting them wish that they had. I don't know what the HP increase is from a basic streetport, maybe 20 or so HP depends on the mods really. Porting will also add extra potential for the future such as spooling larger turbos sooner and cracking higher HP numbers easier etc.