I am installing a 2005 LS2 Corvette engine with a Tremec 5-speed in my 67 Roadster "Big Block" and wonder what type of front springs I should use as the engine is much lighter. I also plan to add offset trailing arms in the rear to use a larger tire and wondered if anyone has experience with them and could suggest a tire size - max 10".

 

I used double offsets from Van Steel on my 64. The e-brake bracket is relocated on top of the T-arm. Proper rim back spacing is key to maximizing tire width. I converted to disc brakes to fit 17x9 rims with a shortened rear main leaf. Backspace on the rims is 5.9". Tire choice is critical as well. Some tire brands are dimensionally different even within the same tire size. I managed to fit 275/40/17 BF Goodrich GForce KD's on the rear (255/40/17 fronts) without going to flares. I'm not sure about other tire brands. There is approximately 1/4" clearance on either side of the tire. My car is also lowered so that tells you how trial fitting everything is critical to making this combination work. The same exact setup on a friend's '66 big block netted only about 1/8" clearance. He had to shave the inner fender lips and pound out a dimple on the frame to make it fit. Very tight. This just goes to show the subtle difference in frame tolerances on various midyears. This setup is about the largest tire you can go on a midyear without flares.

I'm sure others will chime in on their setups but probably a narrower tire/rim combination would be a safer bet. If you go to 17" rims I would think that that a 245/17 front (with bumpsteer kit) and a 255/17 rear with proper backspace would fit without too much grief. Just remember I had a lot of professional help and some trial and error on a shop lift to get my setup to work.

Your LS2 setup sounds great. Keep us posted on the install and results.

Allan

 

That helps with the rear. Anyone have comments on what Spring rate I should use on the front.

 

If you're serious about modifying the front end, get the VBP front monoleaf spring conversion. That has adjustable spring rate and adjustable ride height.