Hello Guys,
I need your wisdom. I've got an almost new 360 truck engine ( inverted 105 block ) with all new parts in it. Since it hasn't got the power to get out of its own way, I'm thinking about hopping it up. I want to make it look like an early model 352. I bought a 63 four barrel intake, looking for early valve covers and I'll put a descent cam kit in it. The heads are D model and I plan on achieving @ 63cc combustion chamber volume.
Now that you know what I'm planning, tell me if the 391 ford piston ( Comp. Ht.= 1.882, 25cc dish volume) will work in the 360 engine. Same bore but it'll be sticking out of the jug by .002. Will the valves hit. It's got the 25cc dish in middle of the piston. Silvolite 3176H part no. Has anyone done this before.
Thanks for listening. Jim

 

I just did a real quick read on your post..and .002" out of the hole shouldnt effect it..I think Polcats running .004" out and back when Ratsmoker was here..he was running .005" out of the hole..So I think your good to go?

RJ

 

Interesting. I think it could work.

Will the valves hit? Depends on the cam. At worst, you friendly local machinist may have to have valve reliefs cut into the pistons. No big deal.

Or, if you can find .060" over 352 pistons, they will work in that block bored .010" over...

Oh, and that's an FT 361 piston.

 

Isn't "High Performance 360" an oxymoron?

 

You gonna turbo charge this thing? You'll need something to boost the 7.2 to 1 comp ratio with those pistons. Probably need to rebalance the thing too for those heavy suckers.

 

Yeah, there is no such thing as a 360 truck motor. They were designated as 361 to not be confused with the pickup 360 motor. The 361 has the 7.4 compression while a 360 has 8.4 compression and if you dont think that makes a difference you've neverdrive the 2 on the same day. The 391 motor shares the 7.4 compression.

 

361= same bore/stroke as the 360. Using 361 pistons in a 360 will yeild the same comp ratio as in a 361. 359 is also a 360 truck engine. Same crank as the 352/360, but with 361 pistons. 361 had steel crank.

 

Bear and BadDad,
My calculations with a 63 cc head would be 9.1 with the .020 gasket with 4.4 opening , 25cc dish piston, 1.88 compression height and -.002 deck clearance. I think the compession ratios you mentioned are for stock applications with stock head cc volumes. Am I wrong. Thanks, Jim

 

Bear and Bagdad,
Just realized, the 361 has the same stroke as the 360 but it doesn't use the same rod. The 361 uses the 390 rod which is shorter and drags the compression down with excess deck clearance. My plan was to not change the crank and rods, just get the compression up with different pistons. I was wondering if anyone had tried this combination before. It seems feasable. I know it won't set the world on fire but my old buick 3800 cc car seems like a rocket compared to a stock 360 engine.

 

Why all the screwing around, when done still a 360.
Why not locate a used 390, rebuild it and be done?

 

First I've heard of the 359/361 using the 390 rods, but it does make sense. But that doesn't change the fact that those pistons are huge and heavy and you'll have to rebalance the whole thing to make it work. I agree with Beemer, stroke it and be done with it.