What would you build if limited to 372ci - with boost as an option

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33IMP said:
For a street car, or drag car, I probably wouldn't bother.
For a salt car, I would assume you would have to do anything possible for durability sake.
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For this discussion, I was looking for everyone's input on what to build to get below 372ci. It isn't a deal breaker if it just doesn't make sense, but lessening a record by 20mph is huge.

Is my math right? If so, it seems doable for a displacement regulated class.
 
You had better talk to your crank guy about that .275 destroke. I'd bet you can't cut it that much.
I think the most you could destroke it, and still use a bbc rod is .205, and that's if the crank grinder is perfect.
To destroke more than that, you'd have to use something else, maybe a long small block rod. I don't think you can find a small block rod long enough, unless you go to a custom aluminum rod. And the crank would be seriously thin, if it doesn't already have a "window".
 
33IMP said:
You had better talk to your crank guy about that .275 destroke. I'd bet you can't cut it that much.
I think the most you could destroke it, and still use a bbc rod is .205, and that's if the crank grinder is perfect.
To destroke more than that, you'd have to use something else, maybe a long small block rod. I don't think you can find a small block rod long enough, unless you go to a custom aluminum rod. And the crank would be seriously thin, if it doesn't already have a "window".
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Another option. Take crank down 3.21 and use chevy rods which are 6.535. 364 inches from a 383 and off the shelf rods. Just need factory piston with 990 pin
 
About 50 years ago, when nhra was playing around with car weights in prostock (to make sure the chevies won, and mopars didn't, just like today) there were destroker cranks available for Hemis, to make smaller than 426 engines, so the car could,be lighter.
Good luck finding one. I think there might have been two strokes available. I remember 366 and 396 hemis in prostock.
 
I think you are trying to use shelf pistons. I just don't think that is remotely possible, cause I think your 3.21 crank solution is not possible.
I think step one would be to assume you will need custom pistons for anything you put together to work at 371 (or less).
 
71GSSDemon said:
Another option. Take crank down 3.21 and use chevy rods which are 6.535. 364 inches from a 383 and off the shelf rods. Just need factory piston with 990 pin
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That would theoretically need a 1.84 compression height piston, according to my math. What is the ch of the pistons you want to use?
 
33IMP said:
I think you are trying to use shelf pistons. I just don't think that is remotely possible, cause I think your 3.21 crank solution is not possible.
I think step one would be to assume you will need custom pistons for anything you put together to work at 371 (or less).
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I would assume custom also at this point.
 
33IMP said:
That would theoretically need a 1.84 compression height piston, according to my math. What is the ch of the pistons you want to use?
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My motor is a 68 which should have the 1.920 CH positive deck pistons I believe.
 
All measurements theoretical blueprint specs, but.....
1/2 c4ank stroke (depending on if you think it's 3.38 or 3.375) plus a 6.358 rod, ppus a 1.92 ch piston comes out to 9.965. So theoretically .025 in the hole with a 9.98 deck.
Of course, ALL of those dimensions can be off, from crank grinding, deck cutting, or over-height deck from Mopar, to reconditioned (shorter) rods.
 
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