Trying to time a mystery motor

jmans

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Hey ya'll

New to the forum but excited about my project!

Have a 1965 Pontiac Catalina with a later 70s Pontiac 400 and TH400 swapped in that I am working to sort all the issues on.

Have an issue with the car right now with long crank times and won't idle without a bit of help on the throttle until it warms up a bit.

I am looking at the timing and from the videos I watched there should be timing marks with the degrees on it but all I see is this thing poking out and these two marks on the balancer.


Are these the marks for TDC from Factory? any advice on where to set initial timing or timing in general on this kind of set-up?

This is some of the information on the motor I found which makes me think it's a 1974/75 400:

I haven't been able to get to the date code next to the distributor (Gunk and the angles make it difficult without pulling hood or distributor)

But these are the codes I have been able to locate:


Next to the water pump:
V245836
YT
Off the heads:
56/8 (Above exhaust manifold) A065 (below valve covers)
On the block passenger side by distributor:
481988 (In the spot for later motors so checks out)
Exhaust manifold has this number stamped on it:
9779033
 
I think someone installed a 389 damper and timing cover on your engine. The YT and the engine casting number 482988 point to 72 to 75 400. The damper is marked for 0 and 6 degrees.
 
Am I still able to time it with this or should I replace the timing cover and damper?
 
Am I still able to time it with this or should I replace the timing cover and damper?
You can time it but unless you make your own marks the best you have is 6 BTDC
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You can time it but unless you make your own marks the best you have is 6 BTDC
Looks like I'm going to have to play it by ear, we have a limited driving season and I don't want the car to be down while I try to replace these parts to time it.

I appreciate your help!
 
Looks like I'm going to have to play it by ear, we have a limited driving season and I don't want the car to be down while I try to replace these parts to time it.

I appreciate your help!
Just measure the distance between the two marks and add a 3rd one which will give you 12 BTDC
 
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