Calling expert engine builders.....'77 360 build

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65Val

65Val

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Helping a friend with this 360 build. Here's what we've found. Pistons are EngineTech 1530's @.030 overbore...dish (we think) is 10.8 cc's...head chambers cc'd out at 65cc's. What'y'all think? Are we out to lunch?

Thanks huge in advance!!!

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i get 9.42 using the diamond pistons calculator and using .25" down for the first ring, 4.18" gasket bore and .040 thickness.
 
United Engine calculator shows 9.5 so you're right in the ballpark.
 
That 284 will want plenty of cylinder pressure to not be soft on the bottom. Especially the wide LSA version. IIRC that puppy is 241@.050

If alloy heads;
I ran the 292/292/108 Mopar cam(249@.050 as I measured it) with alloy heads for one summer and change, trying to make it work with 3.55s, (which was a bad idea).
So I switched to a smaller cam(223/230/110@.050) and readjusted the pressure and ran that for a few years.
When that cam died, I went to the next bigger cam (230/237/110@.050), again adjusting the pressure.

In total, this engine has over 100,000 miles since 1999, and it has always run right around 177 to 185psi, and has always run 87E10 with full timing.
Of the three cams, I liked the 223 the most.

But if iron heads; IDK. I think you will be somewhat limited in the pressure department.
 
Did you actually messure the piston hight ? I really think .025" down is very optomistic unless you have decked the block. Probably a lot closer to .050"
 
OK, things have changed. My friend added a zero to the deck height...should be .15, not .015! That kinda changes things a bit. Now the chart says 7.64 compression...OOPS! Now he's thinking of different pistons, or running the low comp and a Whiplash cam?

Which would be best?

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65Val said:
Ok, what can I recommend to him for pistons? He’s not looking for a top fueller, just a nice street engine with a bit of lump… probably a cast or hyperU ?
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Is the short block assembled or with only one piston installed?? He already has all the parts, why not call some cam companies and get a grind that will compliment what you already have?? No need to think themselves out of good parts that actually will work absolutely fine, IF a cam and other related parts are selected to compliment. I wouldn’t be concerned with the lower CR and would be calling a cam grinder and then assemble it! What he has now is perfectly fine with complimentary parts. :)
 
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12many said:
Is the short block assembled or with only one piston installed?? He already has all the parts, why not call some cam companies and get a grind that will compliment what you already have?? No need to think themselves out of good parts that actually will work absolutely fine, IF a cam and other related parts are selected to compliment. I wouldn’t be concerned with the lower CR and would be calling a cam grinder and then assemble it! What he has now is perfectly fine with complimentary parts. :)
Click to expand...

All 8 pistons and crank are in. That's it.
 
pull it apart and through in a set of sealed power h405cp pistons . $150 a set with rings off ebay , you will have to get a machine shop to press the pins for you , mine charges $40 the h116cp pistons are $300 for a little more compression
 
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