Basic 318 info needed

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Frank1669

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I have 2 318s that both run well 1st is a 1972 in 3/4 ton 4x4 pick up... the second is a 1988 1/2 ton 2wd pickup motor.. is one short block better than the other? is one set of heads better? I Don't know the specifically what cam I will install but it will be a small RV type Think like an Edelbrock performer cam, My understanding is I will need to change the oil pan and pick up to fit in an A body.. Will the pan and pickup off the 360 in the car work and do 318/360s use the same flex plate? Thank you
 
The flexplate is the same. However, the torque convertor for the 360 is weighted for external balance. The pick up tube will work. The pan will not. The 360 is smaller where it seals around the rear main cap. Both heads will be typical small valves for a 318. The 88 heads should be 302 castings. Flow is supposed to be better. They are crack prone, though. Short blocks would be basically identical. 88 might have a roller cam. Nothing in the way of performance though.
 
Peel the intake off the 88 engine just in case it's a roller cam engine. Those started in 85 in the cars but I am not sure when and if the trucks got them.
 
The 1972 3/4 ton block may have a steel crank and thicker cylinders. I've got two truck 1973 half ton truck 318's, and one has industrial thickness cylinders and the other doesn't, YRMV. The '88 half ton engine should be a hydraulic roller engine with 302 fast burn heads and close to 9:1 compression. If it does have the hydraulic roller cam, send it to Ken Heard at Oregon cam grinders for a regrind. You'll need a 318 car type pan for it, but as noted, the pickup out of the 360 will work. I would look into the 3/4 ton block a little closer. If it has a steel crank and you have any plans for a fairly hot small block, hang onto it. Chances are good it could go .090 over (4.00 inch bore) if it has a steel crank.
 
Frank1669 said:
I have 2 318s that both run well 1st is a 1972 in 3/4 ton 4x4 pick up... the second is a 1988 1/2 ton 2wd pickup motor.. is one short block better than the other? is one set of heads better? I Don't know the specifically what cam I will install but it will be a small RV type Think like an Edelbrock performer cam, My understanding is I will need to change the oil pan and pick up to fit in an A body.. Will the pan and pickup off the 360 in the car work and do 318/360s use the same flex plate? Thank you
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No, the 318 pan is not interchangeable with the 360 pan... The rear radius for the rear main is different...

Any pan from a 273, 318, or 340 will work...

The 360 pans have a unique rear main radius....

How to ID a Small Block Oil Pan 60's - 80's
 
99.89% that '88 will have a roller cam. That is better on the street for a few reasons, cam break-in is a no problem and you don't need to worry about adding zinc. I also think there is an advantage in the pistons/deck height maybe?? My mind is fuzzy... lol. Both engine can and will serve the purpose.
 
A couple more questions need to be answered to confirm choices. What year A-body is this engine going in, and which transmission is being mated to it?
 
The oil pickup will NOT work if you are changing from a rear sump to front sump pan. I am a bit confused about what you actually have.

On a side note, I actually converted two pans from 360--318 LOL sometime in the late 70's. Cut out the rear "half moon" with a makeshift jig on both pans, bolted them to an old 273 block to control warpage, and gas welded them into the opposite pans.
 
Most has been said, roller cam, 302 heads and such. You won’t know which is the better block till you have it sonic tested for cylinder wall thickness. Guaranteed the 88 is a thin wall casting, but may have core shift so sonic test both.
 
My vote is for the 88 engine. I swapped 318s in my 87 ramcharger for one that was an 88. Has the factory roller cam, #302 heads and the pistons were .018" on the hole compared to the 87 motor that was nearly double that. I rebuilt the 88 completely stock and the power difference is night/day to the non-roller 87 motor.
 
I'm all in for the '88 engine, too. A little bit of cam, intake, and headers goes a long way with the decent compression and good deck height.
 
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