Finally got my compression done on the engine stand yesterday. had to rebuild the starter solenoid before really getting started (), but it went pretty smoothly after that.

since I didn't have a cooling system hooked up at the time, I couldn't really warm the block with the block heater. Also, the barn was unheated for the week leading up to the test and it was snowing outside at the time of test.

so, I think its pretty safe to say the engine block was dead cold during test.

that said, my numbers are little lower than I believe they should be, but using some high school physics knowledge (pressure is directly proportional to temperature), I think I'm looking pretty good.

all of my cylinders were between 325 and 340 psi, so the consistency was quite good.

then, for kicks, I did the math on what the numbers would be had my block been at operating temperature (assuming an operating temp of 215F and a temp of my block at 32F). ...I also threw in Glenn's recent numbers as well and an estimated block temp of 100F since he said it was ~45F outside at the time and he had plugged it in "for a few hours" :-)



I doubt we'd see numbers like that if we did our tests hot, but I would bet we'd both clear 400 psi across the board so that's good news!

now on to getting this sucker built back up with all the go-fast goodies!

 

Looks good JP!

 

Yeah, I was pretty happy with it - after doing the math. Another factor I have heard that I didn't account for is improved sealing of the rings with a warmer engine - with the aluminum pistons presumably expanding in the cylinder. So, I'm feeling pretty good with my numbers.

Now the fun job of pulling the turbo and exhaust manifolds...

 

That's really interesting JP, good job. So, have you decided to tear it apart or just do some mods to it while its out? I forget, is this red, white or blues motor and how many miles on it?

 

I think I'm going to do just about everything but remove the heads - front and rear seals, lpop, and all the mod stuff... I plan to put a build thread together starting with a to-do list, but prob won't get to that till next week. Still visiting family and friends over the holidays for now.

And this was Red's motor. 199k on the clock, but it had two bent turbo fins, so I was afraid it may have swallowed something along the way. Whatever it was, didn't seem to do any harm to the cylinder walls or valve seats, though, which was my main concern.