ive been researching and they said gm wasnt supposed to send the 350s to be convertible due to twisting issues is this true i know they reinforced it along the pinchwelds and i got subframes so is there a possibility of ruining my car for a big motor say like 383 stroker?

 

I have the same worry so I am just building a mild 350 for my vert and I will be installing the UMI subframe connectors. Unfortunately our cars flex a lot especially the verts. My car cracked the windshield while taking some curvy corners a few miles down the road from my house. I slid the car around a 35mph corner and it popped real loud. No other cars around or anything that could have caused it. The crack runs straight from top to bottom with no star anywhere.

 

That's crazy I really wanted to put something crazy in like 383 tt but looks like that's not going to happen to beautiful of a car to ruin

 

Guess it depends what your definition of crazy is. I plan to run 2 set of subframe connectors on my car (spohn and Alston) as well as a few additional braces to join the two sets into one. There are other members one here who have done the same (bluezee) and they are running lsx's with 375-450 hp no problem (couple people even have a roll cage installed in theirs). I would think so long as your not trying to put like 700 horse in it and beat the hell out of it you should be fine. But I wouldn't do it until after you have sfc's installed.

 

As mentioned above, I have inner and outer subframe connectors (Alston inners, Spohn outers). I also have a strut tower brace which really doesn't do anything for convertibles specifically over a coupe, just helps keep the front of the car tightened up. My car makes 420hp at the wheels and I have plans to bump that to 500rwhp in the next year.

My car flexes when it's on jackstands but that's the only time I ever notice anything. The doors get a little difficult to open and shut when it's up on stands. I've not experienced any problems running the car on the ground/at the track. No windshield cracking, no body popping noises, nothing of the sort. As long as you stiffen it up as much as you can you will be fine.

 

I put out a post for everyone who has a vert with SFC to post what they have and how much it helped. I have UMI SFC on a t-top iroc and I love them. I jack the car up with them but I will probably do what bluezee did and get two pair for the vert. My car really flexes but I must admit that I put it through corners. Thats how I cracked the windshield.