Saw something in another thread I didn't think about. I have a 305 TBI Camaro RS and in the next year or so planning on putting in a 350 and bolt ons to get me to around 400HP, is that going to cause any problems with the T top fbody thats was built with a 175 HP stock engine? I used to work in a car parts stamping plant and the car that were convertable got much thicker runners stamped than the hard top cars to make up stability for lack of the hard top stability.

 

Just get some sub frame connectors, get them welded in and you're good to go. Even without the extra power they help the body feel much more solid (less creaks and groans when driving over uneven road, less rattles developing over the life of the car, etc). On my 86 IROC with t-tops a strut tower brace really made the car feel alot more solid too.

 

just perform the standard suspension/frame mods (SFC's, LCA's, ect.,) and you'll have no trouble

 

Subframe connectors! Weld in, not bolt in!

 

whats LCA's?

 

LCA = Lower Control Arms

Just go with the weld in subframe connectors and you shouldn't have any troubles. I had a 355 that was tearing the body at the top and bottom of the C pillars with a hard top, so I defintaley recommend them as your first mod.

Martin

 

Ok thanks!

 

I have SFC and a 6 point roll bar and never had a problem with the T-tops. I ran for 2 years without a roll bar until I got into the 11's when I finally needed one.

 

whats the use exactly?? I have a T-Top car on top of all my mods, is it really slowing me down all that much. I planned on doing a lot of suspension work (AGX front shocks and a ful rear suspension kit that summit has for like $400) but I never really thought I would be hindered by my T-tops

 

Chassis flex not only causes your paint to crack and peel, it's also a power robber. Just think about it: every time you stomp it, the body of your car is twisting and absorbing some of the driveshaft torque. That's torque that isn't getting to your wheels, which means loss of acceleration. It generally doesn't become a problem till you get above 350hp or so, but even on a stock car it'll stiffen the suspension feel and take away a few rattles. SFC's should be one of the first mods to any performance oriented F-body, in my opinion.

 

Agreed. You would have to make a lot of power to really worry about chassis flex becoming something to worry about in the manner you speak of. However SFCs and the like work very well at tying the car together and giving it a frame of sorts.

And bolt-in ones will do just fine.... You can always weld them in later if you like, but it isn't like the bolt in ones will go ahead and loosen up and fall off on there own... Maybe with some repeated wheel stands or many many hot laps at the road course, but not your average street/part time strip/course car. Most of our cars are bolted together..... like oh, say....... the entire front subframe assembly and suspension .

 

so lets assume 400lbs of torque, will just SFC's do? what else is there? I don't even know what LCA's do or where they go, does a strut tower brace do anything strength wise for the frame?

 

start with the connectors then do the strut tower braces.... then when thats a problem a roll cage will solve all..

 

Thirdgens are unibody cars. There is no seperate frame. The car has subframes at the front and rear to mount the suspension and powertrain to, but the subframes do NOT run the full length of the car. The front one ends at the tranny crossmember and the rear one starts at about the back of the door. The space between is not reinforced, and the car is basically held together by the floorpan. SFC's are just steel tubes that span the gap and tie the two subframes together, which greatly increases the vehicle's structural rigidity. Weld-in ones are better because bolts will allow the SFC to move a little at the mounting points...welds will not. Bolts working loose and falling off the car is not an issue.

A strut tower brace ties the left and right fenderwells together across the engine bay to prevent the deflection that hard cornering can cause. This stiffens the front end but doesn't really provide any extra strength...that's what the K-member does. Aftermarket K-members are unnecessary unless you are a professional autocrosser and need every little handling edge you can get.

LCA's are the bars that go from the rear subframe to the rear axle tubes and keep the rearend straight in the car. The stock ones are stamped steel which is somewhat flexible, aftermarket peices are usually thick steel tubing which is stronger and will deflect less. They help a lot if you have traction problems because they hold the rear more firmly under the car.

The panhard rod (PHR) is what holds the rear centered under the car and prevents side-to-side movement of the rear wheels and axle assembly. Again, the factory ones flex and aftermarket parts are stiffer and stronger.

For 400lbft, SFC's alone should be plenty for the chassis. The rear suspension will need work because you'll have major traction problems, but LCA's, a PHR, and possibly a torque arm will fix that.

Sorry it's so long, but it should help a bit.

 

great info... thanks man