Specs .

Rebuild motor , new parts : Hurley apex , mazda sideseals , cornerseals .
Used but good housings , side plates , rotors etc .

Engine has been run 3 x 20 minutes only so far , test was on warm engine .
I know the compression wil improve during brake-in , but the difference between the front and rear housings seems very large ? , se pics . Also the rpm is somewhat low , but its an indication at the least .

Some inputs guys . ?


Front. Rpm 168

Chamber
1= 7.4 kg/cm - 105 Psi
2= 6.3 kg/cm - 89,6 Psi
3= 6.6 kg/cm - 93,87 Psi


Rear . Rpm 202 .

Chamber
1= 3 kg/cm - 42,7 Psi
2= 4.4 kg/cm - 62,6 Psi
3= 3.2 kg/cm - 45,5 Psi

 

Ummmm.....these readings are almost like an engine on life support...

IIRC, you should be at 100PSI atleast, everywhere.

Who rebuilt that?

 

Hey , !

A so called "well known" engine builder , on of 15-20 rotary guys in my country , hmm , - .

 

First of all, you need to normalize those reading to the Mazda spec of 250 engine RPM and sea level. Your engine cranking speed is way too low like you say. Use the charts in the factory service manual to correct the readings so that you can compare them with Mazda recommended minimum acceptable compression. However, even after correcting the readings, I doubt that rotor #2 will be at or above the minimum. Fully break in the engine and test again.

 

Okay . The engine has now run aprox 2650 miles .
Broken in one should say.


Front. Rpm 246

Chamber
1= 6.5 kg/cm - 95,55 psi
2= 6.7 kg/cm - 98,49 psi
3= 6.7 kg/cm - 98,49 psi




Rear . Rpm 260

Chamber
1= 4.4 kg/cm - 64,68 psi
2= 4.4 kg/cm - 64,68 psi
3= 5.0 kg/cm - 73,50 psi



Its not the parts from top of the shelf ..that has been used we can say .