SBC SWAP IN A 64 BARRACUDA?
Looking to graft a 64 Barracuda to a 68 corvette frame 1st, then install a 350 SBC and M21 4 speed.
It's a FI unit, roller, 450+ HP.
Will the 8.75/3.55 rear hold up with 15×29" drag radials?
Has anyone attempted a swap like this?
You know that Chevy frame is a stinking heavy piece of metal right?
After you get that all put together and safe to drive, you might need a BB.
Or a lot more gear than 3.55s, cuz if I remember right, that Chevy trans has a 2.20 low, check it out. If I'm right, that makes your starter gear a paltry
7.81, which is not gonna play nice with a cammed up Chevy small block, at something like 3600 pounds.....
But I gotta say, that the 2.20 low, chevy box does have mighty nice tight splits;
2.20-1.64-1.28-1.00; splits of .745-.78-.78
But to get off the line with 29s, yur gonna need at least 4.88s for a street starter gear of 10.74
As for me, I like a (normalized to 24" tire) ratio of 9.75. With my 27s that comes to 27/24 x 9.75=10.97. I get that with 3.55s in the back and a 3.09 low in the trans; eat your hearts out, lol.
Ok suppose you don't understand this; I normalize every tire/gear combo, to a 24 " tire, which is a 1 foot radius, and so I can easily equate engine foot pounds to on the ground foot pounds. Of course nobody installs 24" tall rear tires, so all starter gears have to be similarly normalized.
So then, by actually trying nearly every ratio in the Mopar arsenal; by process of elimination, I have come to the conclusion that I like a normalized 9.75 starter gear.
With 27s and a 2.66 low, this maths to an actual rear gear of;
9.75 x27/24 divided by 2.66=4.12.
With 27s and a 3.09 low
9.75 x 27/24 divided by 3.09=3.55
With 29s and a 2.20 low
9.75 x 29/24 divided by 2.20=4.99
So then;
2.20 x 3.55 x 24/29= a normalized to 24" tire of,
6.46 starter gear; which is gonna suck supremely.
