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Marv D · 05-03-2010, 08:59 PM

Woah dude,, you have ANY traction out of the hole with the 700 and those steep gears???? I think the TH and a 4.11 gear with that short 28" tire is a good step. With your 4.11 gear and assuming that 9" convertor is about as efficient as the rest of them,, your around 6400 in the traps. Unless you make more power I wouldn't expect more MPH unless thngs were TERRIBLY off to begin with. So if you change to a 4.30 gear your only going to gain like 300rpm and put it crossing artound 6700. I bet that cam don't wake up till 6000. I know you got a lot of stroke there but I shift my 4" stroke sbc at 7400, cross at 7600. If it's built right,, it will handle it just fine. You know what kind of components you have in there, and if are keeping the valve train in check,, I sure wouldn't be afraid of going to a 4.56 gear and putting some screws to it with a MUCH bigger carb.

but,, that's just my 2¢ . Crossing at 7100 with that cam sure sounds like a better fit to me. But then,,, so would a little more head, more compression, bigger slick, and the slope get's slippery pretty darn quick don't it.

05-03-2010, 08:59 PM	#7
Marv D Registered Truck Offender Join Date: May 2008 Location: hells training ground (aka Ariz) Posts: 3,118	Re: carb size Woah dude,, you have ANY traction out of the hole with the 700 and those steep gears???? I think the TH and a 4.11 gear with that short 28" tire is a good step. With your 4.11 gear and assuming that 9" convertor is about as efficient as the rest of them,, your around 6400 in the traps. Unless you make more power I wouldn't expect more MPH unless thngs were TERRIBLY off to begin with. So if you change to a 4.30 gear your only going to gain like 300rpm and put it crossing artound 6700. I bet that cam don't wake up till 6000. I know you got a lot of stroke there but I shift my 4" stroke sbc at 7400, cross at 7600. If it's built right,, it will handle it just fine. You know what kind of components you have in there, and if are keeping the valve train in check,, I sure wouldn't be afraid of going to a 4.56 gear and putting some screws to it with a MUCH bigger carb. but,, that's just my 2¢ . Crossing at 7100 with that cam sure sounds like a better fit to me. But then,,, so would a little more head, more compression, bigger slick, and the slope get's slippery pretty darn quick don't it. __________________ Still playin with trucks, even at my age! When you're dead, it's only a problem for the people around you, because you don't know you're dead. .....It's kinda the same when your STUPID. I just did my taxes and reviewed my SS statement. Thanks to the current administration it looks like I will only have to work till noon on the day of my funeral.