79 trans am engine identification.

[dafeutz]

Just purchased a 79 trans am which came with the 301, but the guy i bought it from said it has a 400, problem is we cant tell what the engine is and i cant find any numbers on it that seem to identify it. Other than numbers are there any ways to tell which engine it is (dipstick location possibly?) Thanks

 

[analogkid455]

The easy way is to look at the side of the block and it should have cast right into it 400 or 301. The 301 is a short deck Pontiac and has very restrictive dogleg intake manifold runners. If you have a pic of it I can tell you what it is. The 79s came with 400s as well. Last year for them. It could also be a 403 small block Olds. This will have the oil fill tube on the front pad of the block between the waterpump and intake. It sticks up there pretty high so it is very easy to identify. They also offered the 305 chevy. The chevy is easy to identify from many different things but the easiest is, look at the spark plugs. If they are under the exhaust manifolds it is a chevy. Pontiac and Olds engine have them above the exhaust.

Other clues for the Pontiac engines are, the 301 used head casting number 01 in 79. The 400 had head casting numbers starting with 6X. Somebody could have changed these though. Block casting numbers are PWH for the 400 and the 301 had many different numbers that year. It should start with PX.

 

[dafeutz]

My computer is not handling the pictures right now but we looked all over by the freeze plugs and didnt see anything but a "GM14" stamped on there. But we did find out that it isnt a 301 by the angle of the oil filter (evidently the 301 stuck out sideways). Also the car has the (smaller) radiator for the 301 causing it to overheat. My only concern is that it is overheating within 4 miles or so. Does that seem like something else is wrong?

 

[analogkid455]

Yes, there is something else wrong. I have to go to work right now but I will give you some things for you to check out when I get home this afternoon.