429 C6 4:10 ratio performance question

[jbolivar]

Can anyone tell me how this combination will perform? I have a 64 shortbed, with a 70 429 (d0ve c heads if that matters) stock 4 barrel Thunderjet, a stock c6, and a Dana 60 with 4:10 gears. What's a top speed? I want it to be as quick as possible, up to about 70mph. It's just a toy, twice a week driver to work. Thanks.

[Effie]

70 429 (d0ve c heads if that matters...

Heck yeah it matters, those are the good heads!

I have the same 429 except mine's a '68 Thunderjet, heads are the same as what you have. Oh and mine's in a 6000 pound pig - my 78 Bronco, with a C6 as well. Except I have 3.55s in a 9" rear.

4.10s are definitely gonna get you moving off the line, but your highway speed is gonna suffer. That 429 is gonna be screamin when you get it up 60-65mph. With my C6 and 3.55s, I think I was turnin' 3000 rpm at 60mph. [I actually took a pic of the speedo and tach on the way back from the Supernats year before last.]

Have you driven this 429 at all? You do know with those heads you'll have to run 93 octane because of the higher compression ratio. I run 93 and I've got the timing cut back because it was pinging. The performance suffers, but it's still got enough ass to be fun when you put your foot in it. Oh and make sure you've got a free flowing exhaust so those heads can breath out as much as they're taking in.

[Fordified1]

It's going to be quick as hell, but you won't want to run up and down the highway much. Using as tall of a rear tire as you can will help top end speed some... Traction too.

I had a 71 LWB F100 with a 70 Thunderjet, and it was very much a street sleeper. I ran 3.90 gears and 35" tires. Doesn't look like it, but it is 2WD. 3/4 ton springs all around.



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