ok so i have been looking to buy a 1980 rx-7 with 58000 original km (Canadian car) and the owner got a compression test done and it said 180 psi for both rotors so my question is the motor any good and how dose it work with this scale

110+psi = Brand new engine in perfect condition.
100psi = great condition
90psi = avg
80psi = on it's last leg
70psi = you ain't getting anything out of this one.




thanks Jesse

 

anyone know what Iam talking about

 

There is no way that motor made those numbers. Retest compression and make sure you remove the valve from the gauge.

 

le wrong^...to an extent.

the engine CAN make those numbers, but thats because the gauge is being used incorrectly! just trying to explain more indepth for this guy.

if you use a normal gauge it will accumulate the pressure of all 3 faces....when you use a piston engine comp gauge to check the PSI on a rotary youre supposed to keep your finger on the air bleed valve or remove it, and just watch the height of the "bumps" in PSI and see what each ones bumps up to instead of letting it pump itself up, which will give a way higher value, just as turbo II rotor sort of explained.

180 probably means 60-70 PSI on each face..

 

The owner just rattled off a number he is familiar with from a piston engine.

 

so what it sounds like the motor has got some age to it. So how much life do you expect is left in this motor? and is it worth 500bucks for the whole car there are a few mechanical problems like slave cylinder and a lealky shock and just a little surface rust ( iam a apprentice mechanic so the mechanical and body work is no problem) so what do you guys think.

 

like they said, retest the compression, I think the owner was BSing you. make sure you're there when he does it. but for 500 thats a decent deal.