hey i am new to this whole fd thing and i was wondering if someone could tell me what the compresion test should say for me to know the car is in good condition. i really appreciate the help.

 

please anyone?

 

I think that the pulses need to be 90+ psi or higher...but I'm not sure...

 

well i appreciat the trie but i wish i knew for sure thanks

 

The REAL specs should be 100 psi or 7 kg/cm^2. Mazda lowered the official specs to 90 psi or 6 kg/cm^2. Also important is that all of the six readings are consistent.

The numbers above are valid for a cranking speed of 250 rpm and the throttle closed. The engine should be fully warmed up.

 

the throttle closed? is that right, i always though you were suppose to have you foot fully on the gas pedal and then be cranking.

 

http://www.robrobinette.com/compression.htm

 

, I meant throttle open! sorry about that.

 

thanks everyone i will post the results when i get them. then i will post pics of the car if i buy it. thanks

 

ok theses are the results tell me what you think....

Front rotor at 282 rpm

7.4
7.4
7.6 kg/cm2

Rear rotor at 283 rpm

7.5
7.6
7.6 kg/cm2

 

All compression above 7 kgf/cm2, 100 psi is good (no rebuild needed).

Sounds like the engine is in great shape!!! Go for it!

Josh

 

just gotta go there and do the 3rd gear WOT test and then get it if it is good. question, is it hard to put the boost gauge in and how long you think it will take?