I need some advice. I purchased my Chevy II with a rebuilt 230 inline in it. The seller didn't know much about the rebuild, although I did get some of the receipts. I've now decided to install a different cam and I'm at the point where I've removed the front cover, exposing the cam and crank gears. I was surprised to see that the small timing marks on the cam gear and the crank gear do not line up next to one another as they should. In fact, the dot on the cam is 180 degrees away from the dot on the crank. The car seemed to run OK. What's the impact on horsepower from this error? Should I install the new cam in this same manner, or should I install the new cam with the timing marks next to one another as they should be? Thanks for help.
The camshaft turns slower than the crankshaft,,,if you turn the engine over some more,they (the Dots) should line up.
MBHD
I agree. In a 4 stroke motor, the cam turns once for every two crankshaft revolutions. Turn the crank one more full turn and I will bet that your dots will line up.
Yes, that works. I wasn't thinking about it correctly. One more question: What is the relationship between TDC on #1 and the two timing marks aligning correctly? Do I not have to worry about that? I guess if the two marks align, then the correct relationship between the cam and the crankshaft exists for all of the cylinders and I just have to find TDC correctly on #1 and everything should work. Right?
JRJ,
Yup youre right:
#1 has to be at TDC (also slip the timing cover and damper on at some point and make sure that when buttoned up the pointer really says TDC when it is really at TDC).
And then the cam timing marks have to line up when the #1 is at TDC. You can (and should) "Degree" the cam to make sure, but I gotta admit, the first couple cams I did I just set em on the marks and called it good.
DeuceCoup: Thanks. I did just what you suggested and everything went together fine. I installed the new cam, got it started, timed it, broke it in as per instructions, and am now ready for the track this weekend. I didn't degree-in the cam--just don't have the tools to do it. It's difficult enough removing and installing the cam while the engine is in the car and doing it outside my single-car garage. Thankfully, weather was great. JRJ