AJ's Opinion; what size SBM do I need

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Ok you poked the bear ........ again
My advice as to cubes is based on the old adage that for performance, you need a 10 cubes per 100 pounds so a 3200 pound car and driver needs a 318 minimum. Since 1970, I have found this to be pretty good advice.
3200 loaded means about 3000 for the car only. Good luck with that.
Sure you can make horsepower with a 318 just by spinning it. But what you can't do is get bottom end out of it, with the big cam in it.
And street performance is all about bottom end. With the typical 3.23s she don't come alive until AFTER 30 mph! unless by some miracle you can get both tires spinning; and as we all know, spinning ain't winning..
So then you gotta bandaid the combo with stall and gears, to get some low-speed performance back .
So now not only do you have this pipey 318, but you also had to spend cash for the stall and gears and now you are wearing out your iconic318 on the freeway, not to mention wearing earplugs.

OK, granted you can engineer a 318 to get a modest amount of bottom end to go with that crazy cam. No argument. But the vast majority of all guys who come to FABO with 318 power on their minds, want nothing to do with putting proper pistons in their slouchy smoggerteens. They just want to bolt stuff on, to make a fun streeter; which is NOT ENGINEERING. And telling them to put a 268 cam or bigger , into their smoggerteens with no other changes, is just very bad advice. And probably 7 out of 10 guys are gonna say just that.

So if you actually thought about it, you might figure out that I actually am watching out for 318 owners. Not just in their pocketbooks, but also as to their expectations.

Please notice I never said a word about any other engine than the 318.
10 cubes per 100 pounds, sorry I can't remember ever hearing that one.
AJ I have a smogger 440 that makes 520 hp and 545 tq, where did I go wrong. That's stock compression fordge pistons and cast iron 452 heads. Your comments about the converter being a crutch is just ignorant. Cam and converter are just part of a package along with carburetors and gears.
I've said this before you have one idea in your head and its all you preach, you have only one combination in your scope of automotive knowledge and that's what everyone according to you is supposed to build.
In 2022 there are guys building 1000 wheel hp with only 2.0 liters, that's only 122 cid so I don't know how your made up antiqueted formula of 10 cid per 100 lbs fits.
 
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I’ve never heard of that formula ether but I like it for a “Old school/old guy” hot rod formula. It’ll work.

A bigger number would work better. But in general terms for an actual street driven car, it’s fine.

Times 11 for good power, street or street/strip
Times 12 for a beast mill.

No build the engine with the amount of HP per Cube math.
This is really where it’s at. The old saying comes into play here. There is no replacement for displacement.

3500 lbs vehicle =
10 = 350 cubes (340 or 360 engine) = street = 1.3 HP per cube. Mid to low 400 hp.
11 = 385 cubes (360 crank into a 340) = S/S = @1.3 is 483 hp
12 = 420 cubes (4.00 or greater arm) Track 1.3 = 546 hp

Stepping up the program…. 1.5 per cube… 350-372-420
525 hp
558hp
630 hp

1.7 hp per cube (wooooo!!!!)
350 = 595
372 = 632
420 = 714
 
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