S13 Blacktop SR Compression

[bigjacsoc]

I am going to pick up my motor tomorrow and would like to know what I'm looking for when it comes to the compression. I already did a search and put in "SR compression" and who would've know every fucking thread popped up and all I found the the ratio.

So what is perfect S13 Blacktop Compression (highest) and what is the lowest without going into bad compression? I've seen stuff that says anything below 135 is bad but then 160-170 is good, which leaves a big gap between 135 and 160. All input is greatly appreciated.

[garagelu]

Check that the numbers are even across the board. I think thats a little more important than the actual number. You should be around 150psi on each cylinder.

[fliprayzin240sx]

^^^Agreed, 150 +/- 10 psi across the board. But also, per FSM, minimum acceptable number is 125. Personally, I wouldnt take an engine thats lower than 140.

In reality tho, its not just compression you have to worry about anymore. Rod knock is next thing you have to worry about. Shitty part, you wont know till you run the engine. Make sure who ever you get the engine from will take it back if it has rod knock.

[bigjacsoc]

Well there's a place here in GA where the two people that own the shop fly to Japan, test drive cars while they're running (only pick descent running cars), buy the cars, then strip everything out of the car (motor, gauges, interior,aftermarket stuff, VLSD, etc.) and then ship the 13 or so different cars' parts to the U.S. Also I paid in advance so they guaranteed me the motor with the best compression of the 7 that are S13 blacktops.

[fliprayzin240sx]

Well there's a place here in GA where the two people that own the shop fly to Japan, test drive cars while they're running (only pick descent running cars), buy the cars, then strip everything out of the car (motor, gauges, interior,aftermarket stuff, VLSD, etc.) and then ship the 13 or so different cars' parts to the U.S. Also I paid in advance so they guaranteed me the motor with the best compression of the 7 that are S13 blacktops.

Sounds iffy, not a lot of folks can afford to run operations like that. Most engine importers have contracts with numerous junkyards all over japan and just sends them whatever they have to fill up a container. And thats usually after the locals are done with the pickings.

[BlitzRPS13]

Take the valve cover off also.. that can give you an idea if the motor has been taken care of also.