ive got a used motor i dont know much about, its a 350 5.7l tpi from a 91 firebird. i dont have the manual for this motor i need to make sure im doing this right.

i know i should charge the batt, disconnect iginition and fuel, and get the motor warm. is there anything else? not sure how to disconnect the fuel. but for the ignition i just remove the main coil wire right?
also what is the psi rating i want to have for a healthy motor?

 

if the engine is still in the car and it runs correctly then pull out the INJ fuses in the fuse panel. This will disable the injectors. You could also just unplug the fuel pump relay. Also, remove the coil wire. Screw the compression hose into the cylinder you want to test and crank the engine over 4 rotations. Pay close attention to the reading on the first cranking rotation. Ideally, you want all 8 cylinders to be the same or no more than 10% difference. I did mine last week and got 185psi.

 

sounds good thanks for the info.

 

I forgot to add that you will need to keep the throttle body wide open to do the test.

 

so just floor it while cranking the motor or ..?