anyone have 355's w/ c-4?
 

if so how do u like it ?
3000 rpm in 3rd =??mph
what size tires do u have?


thanks in advance for your help,
tinner

You're gonna have to state your rear-end gear ratio before anyone will be able to give you an accurate comparison.

I think he wants to know about a 3.55/ 1 rear axle ratio using a C-4 auto trans. I use a 3.25/1 8" Traction-lock in my '66 coupe with a C-4. Rear tires are BFG 235/15 Radial TA's. It runs 3000 RPM at 70 MPH and that's about as much as I can stand for cruising. A 3.55/1 in my car would run (3.55/3.25 X 3000=3275) and that's a little more than I want to cruise at. If cruising is not a factor, then the 3.55 wouldn't be much of a problem just driving around town or at the strip.

Rev

With 235 60 14 tires (25.1" tire diameter), 3:55 rear end, and C-4 my speedo says 50 at 3000 rpm, it is probably closer to 60 mph.

Ah! I though the 355's were his tire size.

Well, with 3.73's and a FMX tranny (same ratio's as C4), I turn approx 3000RPM at 60MPH.

I have 3.50 gears. Before I changed to an AOD I had a C-4. At 3000 rpm I was doing just over 60 mph with 225/60R15's. The rpm would drive you nuts and make you cringe if you pushed it any harder.

With the AOD it drops it about 800 rpm or so. I don't have a lock up convertor, just the O/D. Changed it to an Art Carr convertor. Really made a difference on acceleration.

Thanks for the help guys . I have 235/45/17's so 355's should be good for me . I had a third member built for me for $250.00 he said that was a good deal . Was it or did I get burned?

Hey tinner did you ever lower your car? And if so any pics? I believe it was you who said you were going to lower it awhile back. Not quite sure.

If the 3rd member is a Traction-lock, the $250 is a great deal. I paid $650 several years ago from Currie in Ca. and that included shipping to Houston. That was for a complete unit, (I still have my old one). If you don't have limited slip, you ought to get that same guy to put it in for you.

Rev

rev,
It's not a Traction-lock I went cheap for now , I will need a 9" when the new motor goes in .


1969Mach1,
Yes I did lower it some it still is coming down one more inch , I do have pics I will post them when I get them back.

Click on this link to see a chart of exactly what to expect

http://home.earthlink.net/~gp2mff/gr/bad355.htm

A good 8" Traction-Lock with a C-4 , is OK up to 300 HP or a little more. Some of it depends on what the torque curve is on your engine.

Rev

thanks for the help guys , the gears are in and my car feels much faster.;)

I was roasting my tires running a non posi 3.55 gear in my rearend. Of course I am running 414 HP so there you have to factor this in too. Get into a 9" Posi as fast as you can. Run a 3.50 or 3.70 if you don't mind the revs or a 3.25 or 3.00 if you want a freeway flyer.

I went with a 2.5 gear ratio and Posi when I put in a Granada 9" rear end. I love the traction, and it is really great on the street. I have a 4.30 Posi set up for drag racing when I feel the need for speed.

With the 3.55 gears and the C4 my car was reving pretty high at 75 to 80 mpg which is where I like to be on a freeway. With the 2.5 gears I should be able to hit 165 mph.

Yes I do have good brakes, 4 wheel disks and KEVLAR pads with cross drilled rotors.