FE Power Forums
FE Power Forums => FE Technical Forum => Topic started by: 62_BattleBird on May 29, 2023, 01:43:09 PM
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Please forgive my ignorance as this is my first engine build, but I've got some questions about piston size, compression, etc. Here's the specifics thus far:
Car: 62 Tbird Convertible street/strip (pump gas but I don't mind using an octane boost)
Block: Robert Pond Motorsports big bore 427 iron block
Bore: Machine shop says it'll be 4.375 final bore size
Heads: Trick Flow
Rockers: Harland Sharp Roller Rockers
Crank: Forged 4.250
Intake: I have both a Blue Thunder 2x4 and a TFS Tunnel Wedge 2x4
Pistons: ? ? ? ?
Rods: ? ? ? ?
I'm to the point of purchasing need to purchase rods and pistons but I'm not sure what to do. The only 4.375 pistons I can find on Summit are for Mopar (does that matter?). Do I need to have the pistons custom built? Also, what do I do about piston top (dish, flat, etc)? Any help at all would be greatly appreciated!!
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You are deep in the custom piston range, need to figure out finished bore and deck height, likely end up somewhere around 1.325 with a 6.70 rod and the dish you'll need depends on use, but it'll be a big one at that size. Depending on use, I'd probably go 2618 alloy, but if all street, the 4032 is very good and can run a bit tighter tolerances
Brent will likely chime in, he can get you what you need from Racetec
As far as rods, I like Molnar at that power level, K1 Technologies are also good, very similar, tiny differences in bolts, and you can go up from there. Stay away from regular SCAT or Eagle at that range. Heavier and lower quality
As far as the BT 2x4 or a TW, I am a single plane guy, especially with cubes, but can't go wrong with either
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Ross, the 1.325 CH would be for a 4.25 crank. 1.275 would be a better CH.
I got my custom Ross pistons through Mark O'Neal @ Probe. 480 393 0800
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Crank: Forged 4.250
Ross, the 1.325 CH would be for a 4.25 crank. 1.275 would be a better CH.
I got my custom Ross pistons through Mark O'Neal @ Probe. 480 393 0800
Frank, one thing I learned after 25.5 years in the military - RTFQ
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Sorry about that, Ross but, why not a 526 at this level.
I learned after 25.5 years in the military
I learned I didn't like the military after only 2 yrs ;)
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Because there are no 4.375” cranks available unless you go to a $2500 custom crank.
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Echoing the group here. You are going custom piston. No option about that.
I would consider the Molnar rod as a solid choice at this level - upgrade would be to a Callies...
Intake choice is a usage thing. Normally I steer street stuff into the dual plane. They have an enormous torque advantage below peak. But this displacement alone means you won't have a shortage of torque no matter what.
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Thank you all so much for the detailed insight! I truly appreciate it.