[Snowe]

Alright so I need some advice on how to approch stiffening the chassis on my 2000 GT Convertible to handle a ~723 RWHP Engine I bought after my cousin crashed his Cobra at the strip. I do not plan to be launching this car at the strip and plan to use it more for road racing(at a track)/Bragging rights. I will state now neither money nor time are an object and I just want this car to say I did it and it can be done. The car already has installed a Maximum Motorsports Road/Track box with subframe connectors etc. I plan on adding a 6 point weld in roll cage as well to stiffen up the chassis. I have a 31 spline LSD and Axles. I will upgrade the drive shaft to handle the HP. Upgraded Torque box as well. The motor will come with the tranny so that should already be setup to handle the power. My main concern is with every available chassis strengthener on the market installed the convertible will still crumple like a tin can under that much power. So that is why I am here.

What can I fabricate to make this car survive? Is there something on the market I don't know of that will be the end all to my troubles? I know I could just buy a coupe and call it a day but that's just not as fun as saying I have a 700HP convertible. We were actually discussing at the shop today welding the doors to the body and gutting them. Then running steel tubes down the inside the length of one quater pannel to the other. Converting it into a roadster without doors actually sounds pretty cool because you wouldn't be driving a 700HP stang in the rain anyway.

Any advice outside of "you're wasting your time" is greatly appriciated.

 

[SoCal2V]

I think you've pretty much got it covered with the 6 point bar (and all the MM stuff), no need to go full Dukes of Hazzard and weld the doors shut or anything.

The only thing I think might be better than the MM subframes is the Kenny Brown matrix sfc's.

Depending on how serious you are about doing a/x events (700 hp is going to make that very interesting, btw), you should type "Jazzer's Official Suspension Guide" into Google. Well written and illustrated tech write-up by a guy named Jazzer the Cat who is active on a couple of other Mustang forums.

 

[Snowe]

I think you've pretty much got it covered with the 6 point bar (and all the MM stuff), no need to go full Dukes of Hazzard and weld the doors shut or anything.

The only thing I think might be better than the MM subframes is the Kenny Brown matrix sfc's.

Depending on how serious you are about doing a/x events (700 hp is going to make that very interesting, btw), you should type "Jazzer's Official Suspension Guide" into Google. Well written and illustrated tech write-up by a guy named Jazzer the Cat who is active on a couple of other Mustang forums.

Alright I'll look into that. I wasn't sure the 6 point would be able to stiffen the chassis up enough with the car being convertible. I'm not sure how much difference there is in the rigidness of a coupe and vert in the first place. I just know when I put the MM SFC in the only thing between the front and rear subframes was the floorpans which don't seem very thick. My biggest fear with dropping that plant in there is a cracked windshield or ending up with the car rocking between one rear and one front tire.

 

[JonR2006]

I would second the Kenny Brown Matrix connectors. Also, with that much power I would advise a watts link or a beefy panhard bar/TA setup; especially seeing as how you may want to road-race. Welding the axle tubes is a must...Full coilover suspension is probably a must too.

A member on here (haven't seen him in awhile though) has a 98 convertible with 650+ to the wheels...he would be a good resource (username is WillyG or something....I will have to post back with his actual username later)...

 

[willyg1997]

I didn’t really find what I was looking for in the aftermarket department, so I built my own sub frame and 6pnt roll bar. The roll bar is mounted directly to the sub frame, not welded into the floor pan. The weld in sub frame is 2”x2” with .25” wall, with cross braces to tie into the ca box and roll bar. Yes it is heaver then your aftermarket, but makes the vert feel solid as a rock.