Compression & Cylinder Leak Down Test

[GoFaster06]

Just got car back from doing a compression & cylinder leak down test. Results are as follows: Compression: 1=204, 2=200, 3=196, 4=206, 5=190, 6=184, 7=200, 8=193 (all within 10%). Cylinder leak down test: 1=8%, 2=4%, 3=4%, 4=2%, 5=13%, 6=3%, 7=4%, 8=7%. Tests were done on cold engine, they had issues with getting correct adapter). Shop stated both test #'s would be higher on a hot engine.

Are these #'s within normal range or should I be concerned about anything. Shop said #5 (13%) has a piston ring seal leak. I had these tests done since I'm trying to pinpoint power loss. I've done all the smaller things, now looking at possible engine, supercharger problem.

 

[86GT351]

Just got car back from doing a compression & cylinder leak down test. Results are as follows: Compression: 1=204, 2=200, 3=196, 4=206, 5=190, 6=184, 7=200, 8=193 (all within 10%). Cylinder leak down test: 1=8%, 2=4%, 3=4%, 4=2%, 5=13%, 6=3%, 7=4%, 8=7%. Tests were done on cold engine, they had issues with getting correct adapter). Shop stated both test #'s would be higher on a hot engine.

Are these #'s within normal range or should I be concerned about anything. Shop said #5 (13%) has a piston ring seal leak. I had these tests done since I'm trying to pinpoint power loss. I've done all the smaller things, now looking at possible engine, supercharger problem.

I would worry about number 5. Still working but only going to get worse.

 

[Marc s]

I would worry about number 5. Still working but only going to get worse.

Agreed.

 

[GoFaster06]

Agreed.

By getting worse what will start to happen?

 

[Marc s]

You will notice more blowby and then less power. Then, it will start to idle rough and throw missfire codes.

 

[86GT351]

You will notice more blowby and then less power. Then, it will start to idle rough and throw missfire codes.

Correct. You are at a very fragile point. Still working but not causing major issues yet. Will only get worse if nt addressed.

 

[GoFaster06]

You will notice more blowby and then less power. Then, it will start to idle rough and throw missfire codes.

How much does it usually cost to fix?

 

[Marc s]

If you remove and install a new engine with forged components, $4,000.00 If you have a shop do all of the work, $8000.00.

 

[GoFaster06]

If you remove and install a new engine with forged components, $4,000.00 If you have a shop do all of the work, $8000.00.

You can't just fix piston ring seal? How much does that cost?

 

[psfracer]

If you are currently running a whipple @ 10psi, just save up for a forged short block. I think it would be kind of silly to do all of the labor of removing the engine, tearing it down, rebuilding, and reinstalling, and put back in stock components when running a whipple at 10lbs already.

 

[CraigNnem]

If go through all the trouble of removing and taking the motor apart, you might as well use better components when putting it back together.

 

[GoFaster06]

If you are currently running a whipple @ 10psi, just save up for a forged short block. I think it would be kind of silly to do all of the labor of removing the engine, tearing it down, rebuilding, and reinstalling, and put back in stock components when running a whipple at 10lbs already.

Like this.
http://www.brenspeed.com/b326.html

 

[Marc s]

If you are currently running a whipple @ 10psi, just save up for a forged short block. I think it would be kind of silly to do all of the labor of removing the engine, tearing it down, rebuilding, and reinstalling, and put back in stock components when running a whipple at 10lbs already.

If go through all the trouble of removing and taking the motor apart, you might as well use better components when putting it back together.

That's the correct answers.