Timing pointer?

[Clos'84TX]

Well I have yet another question, this one is about timing pointers..I have a 350//four bolt main. The engine was swapped to this truck, no pointer is installed. I'm looking into installing one.
What is the difference between a 7 in and 8 in pointer?
Or what would be the best one to install?

[jimfulco]

You need to measure your balancer and buy the pointer that corresponds. The pointer rides about 1/8" to 1/4" outboard of the outside diameter of the balancer, so the 7" pointer won't even fit on an engine with an 8" balancer, and an 8" pointer would be so far above a 7" balancer that you could not set the timing accurately.

[swervin ervin]

This is a question that is asked quite a bit. There is a lot of confusion about all this and I can understand why. GM needed to adapt a standard for this on SBC's but decided to make it hard, like a lot of stuff they do.

Anyway, to answer which pointer is best, either one will work but it all depends on what balancer you have. You see, GM had some balancers with the timing mark at around 2:00 and some at around 12:00. The 6-3/4" balancers used on 305's had the mark at 12:00 and the pointer was built in to the timing cover. I'm not absolutely sure if all 305's are this way but I think so. The 8" balancers had the timing mark at 2:00. I don't know of any 8" balancers where the timing mark was at 12:00, but they were some 6-3/4" balancers where the mark was at 2:00. No 305 had 8" balancers I do know. Of course the reference between 2 and 12 means when the engine is at TDC. Confused yet?

So, you really need to figure out where your timing mark on the balancer is and what size balancer you actually have. To do this you can simple measure the balancer, but you will need to put the engine on TDC at number one cylinder, compression stroke, for mark location.

Then it's a matter of buying the pointer for what you have. Do you know how to find TDC?

[Clos'84TX]

Originally Posted by swervin ervin

Anyway, to answer which pointer is best, either one will work but it all depends on what balancer you have. You see, GM had some balancers with the timing mark at around 2:00 and some at around 12:00. The 6-3/4" balancers used on 305's had the mark at 12:00 and the pointer was built in to the timing cover. I'm not absolutely sure if all 305's are this way but I think so. The 8" balancers had the timing mark at 2:00. I don't know of any 8" balancers where the timing mark was at 12:00, but they were some 6-3/4" balancers where the mark was at 2:00. No 305 had 8" balancers I do know. Of course the reference between 2 and 12 means when the engine is at TDC. Confused yet?

?

By 2 o'clock and 12 you do mean where the pointer should be mounted, I'm positive mine is supposed to be at 2. but for some reason it was never installed, when the engine was installed. My truck was originally a diesel.

I been doing some major fixes, swapped out upper and lower ball joints, brakes hoses, fixed my oil pan leaking problem. And even talked the wife into buying a billet grill for me.