Thread: Fascinating

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As a few of you know I have been trying to bring the vette back to life after a 5-6 year unplanned storage due one of lifes unplanned adventures into near poverty. All is well now.

I have been fighting a poor running 350 cu in engine for a few weeks now. Backfiring, stuttering followed by a few minutes of running quite great. I blamed the ignition so I bought a brand new HEI unit. No change. Bought a new Edelbrock 600 Performer. No change. New plug, wires, cap, rotor etc etc etc. You got it no change. This last week I bought a new set of heads, Vortec 1.94's, and this weekend I proceeded to start tearing down the motor in the car. While I was at it I decided to tear the front of the motor down and look at the timing gear and chain. With the engine at TDC (Crank key at 2 o'clock) the cam gear appeared to be 180deg out. The aligning pin on the cam was at 9 o'clock position instead of 3 o'clock. I took it all apart and set if up as described above and lo and behold the dots on the cam gear and crank gear are aligned. How did this engine ever run? Its been like this for many years.

Remember the cam turms at 1/2 the crank speed, and every other turn of the crank the cam WILL be 180 degrees out.

One little side note on the SBCs, with the cam marks lined up, the No1 piston will be at TDC exhaust stroke, rather that TDC compression. In other words the distributor will be firing No6 cylinder rather than No1 (one reason a lot of guys get the distributor 180 degrees out there first ime rebuilding an engine).

I'm confused. I guess you're telling me that all I did was reset my engine from the compression stroke to the exhaust stroke? Engines are still rather mysterious things to me. This is my weakness cams and engine timing. Alot I don't understand.

Actually you didn't change anything. Had you turned the crank 1 more revolution, you would have found the timing marks lined up. As I said the cam gear only turns half as fast as the crankshaft.

Ok I understand. Ah... that feeling is me getting a little less ignorant.

If we gain a little knowledge during the course of a day, then it has been a good day!!!! Or like my Dad used to say, it's a lot easier to learn when you don't allready think you know it all!!!!! As always, Mike's advice is dead on the money......

Since I don't have anyone that can show me these things I rely on books. Can anyone recommend a comprehensive book on cams, timing and the SBC?