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picklito · 02-13-2016, 11:44 PM

The 200-4r is still on the bench! So, I have the stock 3.08 and TH400 in there. Honestly, it's not bad with 235/75-15's, but run the numbers on a 3.73 and overdrive and it's much better at both ends. Where my 3.08/TH400 runs 2500 rpm, a 3.73/200-4r will be 2024 rpm... and have lower first/second/third gears!

As for carb size, ANY time you're not driving with your foot on the floor, you're not using the whole carb's airflow, right? So if you're building a drag car that's one carb requirement. On the street I hardly EVER put the foot on the floor. And, even though it's a 402, I'm using the truck as my freeway dirt bike hauler. 2 hours each way. So I'm going for as much air velocity, vacuum, and optimized ratios as I can. The truck drives amazingly well and really scoots. Your 383 will light the tires so bad it'll scare you.

02-13-2016, 11:44 PM	#7
picklito Registered User Join Date: Sep 2013 Location: Vacaville CA Posts: 490	Re: 1 pc rear main v 2 pc rear main The 200-4r is still on the bench! So, I have the stock 3.08 and TH400 in there. Honestly, it's not bad with 235/75-15's, but run the numbers on a 3.73 and overdrive and it's much better at both ends. Where my 3.08/TH400 runs 2500 rpm, a 3.73/200-4r will be 2024 rpm... and have lower first/second/third gears! As for carb size, ANY time you're not driving with your foot on the floor, you're not using the whole carb's airflow, right? So if you're building a drag car that's one carb requirement. On the street I hardly EVER put the foot on the floor. And, even though it's a 402, I'm using the truck as my freeway dirt bike hauler. 2 hours each way. So I'm going for as much air velocity, vacuum, and optimized ratios as I can. The truck drives amazingly well and really scoots. Your 383 will light the tires so bad it'll scare you.