Can anyone tell me or suggest if I need to make any modifications to my '69 Chevelle frame if I am going to put 500HP through it, i am presently doing a frame off rebuild and now is the time to do it.

Are you going to be running a 4 spd or trans brake.

Todd

I'm looking at running a Muncie M-22 4 spd.

first buy the hotchkis braces . that will stiffin up the rear frame wher the rear upper trailing arms bolt to. and youll need them with a 4 speed. the stock ones are very week and flex alot.other then that i cant think of any thing else for the frame less boxing it in .down side is it make the car heavy.

When you mention boxing it in, do you mean the side rails along the passenger compartment or the behind the rear axle? Or something completely different?

One thing you can or might need to do is strengthen the lower control arm brackets that are mounted on the frame. The forces from the lower bars push the brackets up (unless you have changed the angle of the bars) and inward. One neat and easy thing i saw someone do is buy a rectangular pc of tubing that has a dip bent in the middle of the tubing for a driveshaft loop. they then fit it in the bottom brackets and welded it to the the frame and bracket. that way they had their driveshaft loop and strengthened brackets. I believe you can buy them at jegs or summit. Alot of chassis companies make them also.

Also I do what chevelle racer told you about also. Those pieces just bolt to the top and lower control arm mounts on the frame.

Todd

i was talking about the side rails.

were you talking about the c channels under the driver and passenger seats. That would help reduce the twisting in the chassis. That's a good idea especially if your not going to put a cage in it.

Todd

I don't really think that 500hp is a level where you need to do much to a full-framed car. Defintely run the 4 speed braces ( I still use the stock ones), solid upper and lower control arms ( boxed), and IF you need a driveshaft anyhow, something I WISHED I did was to swap out the 1310-sized rear yoke for a 1330 or overkill 1350 rear end yoke to use the bigger ujoint.

Even with soft launches, my "maybe 500 hp" 427 is beating up the greaseless Spicer 1310 a bit. Looks like an annual replacement deal.

And yes, I am torquing the caps properly. ( overtorquing the uj caps tends to eat the needle bearings up quick.)

I am fortunate, in that my 'Camino has the heavy-duty boxed frame and the braces that tie the upper and lower rear control arm brackets together.

I went with poly bushings and No-Hop bars, but if I was doing this again, I'd shove in a long arm conversion like those from Hot Rods to Hell. This eliminates all the frame problems inherent in the original four-link rear suspension, and has super street manners, too. It seems like there's no down side other than cost and fabrication.

Hear they ride nice too. Friend used such a setup in his 632 ?? NOS Pro Street truck. Says it rides like a dream.