My Mom gave me my Dad's 86 Corvette when he passed away this January. I am grateful for it. I also knew that it wouldn't run for a few months and sat over winter. When I started working on it. The engine was seized and it needed a starter. I replaced the starter with a high torque and managed to unseize the engine. The fuel system had quite a bit of water in it. I've completely emptied the tank of gas water. Plenty of spark with a spark plug tester. No fire. So, I did a compression test. Ahh!

 

did you lube the pistons before breaking it loose? You may have damaged the rings (or even the cylinder walls).

 

broken timing chain??

 

Yeah, I filled the cylinders with ATF and PB blaster. Soaked it for about a week before it broke loose. i agree, it may have ring and cylinder damage

 

Yeah, it's difficult to say what it is without tearing the engine apart. That may be my only option.

 

It may be out of time. Would that cause low compression?

 

I'm no expert, but it would seem to me that the timing would have to be very severely off. So much that a valve opens on the compression stroke. Isn't that close to 180 deg?

 

What if a timing belt/chain was busted??

 

Not sure what's wrong with it, unless I just start tearing it down. I guess I'll have to rebuild it. This will be my first time rebuilding an engine. So, since I have very little engine knowledge. I wonder how much HP I can get out of this 1986 Corvette L98 5.7L V8?
Any advice and experience knowledge would be very helpful. Thanks!

 

I'm watching an engine rebuild video right now actually (just for fun, because I'm weird like that). It might help you.