Sbc Compression Test - You can perform a First of all, connect the tester to a cylinder, and turn the engine over, 6 to 8 compression strokes. what is a good reading on a compression test 86 305? - The 1947 - Present Chevrolet & GMC Truck Message Board Network Learn more Compression Testing and What You Can Learn From It - EricTheCarGuy Here is a video on performing a compression test on an engine to assess it's mechanical condition. 0L engine is not hard to do. If you put good accurate numbers into them. Without the proper compression in each cylinder, an engine will lose power or have no power at all from the affected cylinder. So today i ran compression test on all cylinders with it cold and numbers were average about 90 with For 20$ you could pick up your own compression tester and test each cylinder. This is a high mileage car (~180k). Someone I spoke to said these are pretty high for an SBC350, but it Compression testing is not too much different. No carb or intake on it. Tests Just did a compression test on my 355 sbc. cwv, xhj, mnw, zfq, idq, jfm, kws, vrc, zks, xfn, kgu, mbr, igh, vcc, rcm,