350 sbc question
 

I have a 350 sbc with a Weiand Action-Plus Aluminum Intake, 1 inch spacer plate, 487X heads with 1.94/1.50 valves, Z28 .500 lift springs and a 278 duration cam with 222 @ 50 and a lift of .467. What would be a good torque converter stall and rear end gears to get the most out of this setup? I use this mainly for street purposes in a 72 fullsize truck weighing about 3500-4000lbs with driver. Some towing occasionally.

I would put in 3.73 gears if you're running bigger than stock tires in the back and have a non-overdrive trans. If you think that is abit steep then 3.55 would be a nice gear and also not too bad going down the highway. If I didn't use the factory converter I wouldn't go very much above stock.

I`d use a TCI saturday night special 2000 stall converter or anything similiar, and some 3.42:1 gears or possibly 3.73`s if your running a tall tire.

I have a rebuilt TH-350 and 265-75-15 tires on the back.

A 265/75 would be pretty tall. Are you sure it isn't a 70 series? Either way I would go with the 3.73 gears. It will be alot more pep without any trade offs around town but going down the highway will be running plenty of rpm.

Yeah, the tires are made by Pirelli. I did some checking and they are about the only ones with that size tire. Right now I have 3.08 gears and they suck with my setup. I usually run around 2200-2400 rpm at 55-60mph. I don't do that much interstate driving, but when I do, I don't want to be running in the 4000rpm range. So, what would be your recommendation?

3.55 will be more what you want.

Ok, thanks. Do these gears have a pretty good launch to them with a 2000 stall converter??

You'll be very happy with the difference from your factory gears.

Are 3.42 and 3.55 about the same? Who carries the 3.55 in a 12-bolt 8.875" truck? All I have found is the 3.42. Thanks!!

3.42 would be fine and still a big improvement over the factory gears. I can't find my little rpm chart for gear and tire size to get rpm. They have them all over the net though. Maybe you just have to bite the bullet and put in some 3.73 I did find those. :D

Off the top of your head then, (lol) what would be the rpm difference between 3.42 and 3.73 gears?

I would say without finding my dang chart. 500-600 rpm's. Just a guess though, I would try to find a gear chart on the net to make sure.

I found a good site for the gear selection. It is : http://www.drivetraindirect.com/html2/calculator2.html

I have 3.54 and a 3000 stall converter, they work very well off the line and on the highway.