My 347 puts out 425 hp and the same amount of torque (flywheel). Behind it I have a hardened T-5 from Astro Performance, balanced aluminum driveshaft, a nine inch rear with 3:70 gears and tracloc. The springs are four leaf and I have welded on subframe connectors. I put no thought into how to get traction until I started driving the car. Right now I have 235r60 15s BF Goodrich T/A tires. The car accelerates like a beast but hitting the accelerator even moderately hard in first or second gear gives me a tremendous amount of tire spin and a squirrely rear end. The car is dangerous to drive hard. Playing with tire pressure does no good. I'm going to look at tires first. Maybe 255/50-17 summer tires on the rear. Not sure about the front. Maybe caltec traction bars? Can anyone with experience with this sort of problem please give me some advise?
Tires. Traction bars. Drag shocks. A 17" tire may not help much. A drag radials would help. But I'd go bigger than 235.
Regarding use of "Traction Bars", here is some very interesting facts, FAQ#8, actually reading all FAQ's..... https://www.maierracing.com/faqs/ David
Thanks. Don't really want to run drag radials on the street. Doubt I would take the car to the track but on rare occasions. Definitely don want to keep my 235's. I want a wide track sticky street tire. 17 inch tires seem to give me a much wider choice.
255/60R15 would be a lot better. And cheaper than a 17. But 17" wheels look better most of the time. Even a 275/60R15 is easily doable.
I looked at the option you mentioned but haven't found a AA traction tire in a 15 inch. Maybe I'm not looking in the right place.
Remember these are`70s technology leaf and coil spring cars which we are attempting to keep moving in a straight line. YouTube is loaded with plenty of videos of both old and new rides laying on their sides or tops after the driver lost control. As greasemonkey points out, 255 or 275/60R15 tires will help regardless of traction rating. Then you have to learn to just peddle the throttle and hang on. Good luck with your beast!
Thanks for the comments but I think you don’t grasp the amount of wheel spin this car generates when hitting the throttle hard in first or second gear, never mind dumping the clutch from a dead stop. I invested at ton of time and money in this beast so I don’t mind going the extra step to bring it all together. The 235R/60-15 BFG’s don’t come close to making this a safe car to drive hard. Not interested in non DOT tires or traction bars. Does anyone have a +425 hp +425 ft-lb with 370 trac-loc who can hook up as well as say a new Mustang GT or Camaro SS? If I went toe to toe with one of these modern muscle cars I would do more spinning and fishtailing than anything else. I believe 15 inch tires have some advantages but can’t locate any supper sticky summer tires for a 15. I don’t mind going to 17 inch if this is what it will take.
Well, since you don't want to do what anyone who ever made one of these cars work with stock suspension did. You won't be able to compete with a modern car with modern suspension. Your car has leaf springs and a short long arm front suspension. With aftermarket suspension ( global west arms and roller perches or coil overs) and custom leaf springs you might be able to do what a cal-Trac or traction bar would do. And for the record my car with a 347 and 4.10 gear with an 8" converter went 7.58 in the 1/8 on a 235/60R14 bfg almost 20 years ago. With traction bars and air shocks.
Why do you not want to run drag radials on the street ? I am not saying they are the answer to your problem but will help some .Harley do you realize that the modern street cars you are talking about weigh 1,000 pounds more than your car, throw 500 pounds of weight in your trunk and see what happens then . I dont know if you have ever driven a modern muscle car but I can tell you that they have problems putting all the power to the ground in first and second gear as well and if they dont they are using traction control feature on their car which basically takes away horsepower when wheel slip is felt Greasemonkey its not fair comparing track traction to street traction and an automatic against a stick car .