69' Coupe Build

[John Grunwald]

hey guys! looking for some advice with my build!
im in need of some new suspension parts, right now I have no modifications to the suspension. the engine is a 331 with around 400rwhp, and all it does is spin the tires. I have 235/60r15 et street radials but they will spin all the way to 45 mph+. Whats the widest tires I can get in the back with minor modifications ( rolling the fenders) with out tubbing the rear.

Im looking to run a low 11 hopefully maybe a high 10 with the right suspension build. At the moment it is a street car but I don't drive it enough to care if the suspension is to rough. Im looking at caltracs at the moment because everyone says theyre magic but I wanna see what else is out there. The rear end is an 8.8 3.73 limited slip.

Lastly, I wanna put a roll bar in so I can set up a 5 point seat harness with some race seats but don't know who sells a pre fabbed roll bar that needs to be just welded in, anyone know the best way to get one? and how much does it cost?

 

[rbohm]

if you are building a drag car, then start with the front and dump the stock springs and shocks, and replace them with stock six cylinder springs and a set of 90/10 shocks. this will let the front end rise quickly and transfer maximum weight to the rear.

in the rear you want to stiffen up the springs to about 220lb rate springs. cal tracs are great for the track as well. for shocks you want a 60/40 or 70/30 shock to control shock compression.

as to the tires, i presume that you are running street tires, if so that is part of your ptoblem. get your self a set of nitto 555 drag radials, they can be run on the street, but will stick to the track like slicks. as to size, you can run a 255 50 tire in the rear with little or no clearance issues. that should be all you need with sticky drag tires.

one more thing, when at the track, disconnect the front sway bar for racing, as that will also allow for maximum weight transfef. just remember to hook it back up before you leave the track.

 

[John Grunwald]

Thanks! And for the rear springs am I able to run a reverse eye with a 1-2 inch drop? Or will there be clearance issues? And what about the split mono leaf from caltrac? It seems too overpriced

 

[rbohm]

you should be able to run the reverse eye leafs, but i wouldnt on a drag car. you want as much weight transfer to the rear as possible, and the reverse eye leafs will reduce that. if you want to lower the car, lowering blocks would be a better choice in your case. an even better choice would be to eliminate the rear leafs altogether, and go with a parallel bar four link system. that way you can get the rear end down and still have all the weight transfer you want.

i havent looked at the split mono leaf system.