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MG MGB GT V8 Factory Originals Technical - Body bracing to handle 200 plus HP

WHat would be need to keep the body from twisting. Sub frame conts? Let me know. Thanks.
Big D

Something for sure. One of the guys around here tweaked the body of his V8 roadster when he tried to race it. (The car's for sale for a heck of a lot of dough, so be careful if you're in the market!) You probably won't like the GT body as much, but I believe it is much, much more rigid (especially if you're talking about cars with more than 1 rust molecule on them) and can accomodate more torque.

Roadster or GT ?

I have 230 bhp in my GT (Works with Jon Eales engine) and have no problems despite no body bracing.


Nigel Steward

The MGB body is a bit stronger than the typical unibody American muscle car due to the fact that it allready has "sub-frame" like connectors welded underneath the floorboards, and those box-rockers help too.

(I want to push around 700hp so i'm converting to tube-frame and 12 point cage.)
James D.

All the best people do it in a GT!!
bob p

the factory installed "top hats" under the RV8 body...they ran from the front rear spring hanger to the crossmember in frontof the seats...welded to floorboards...i've made a set for my car...easy project & easy installation.
Tony Barnhill

It seems like installing a cage would help to keep things taught and rigid. Just a four point or 6 point would work. I'm thinking about throwing a bar with a cross brace in my B-GT. Anyone know of any good manufacturers? I know autopower makes one, I'm very worried about fitment because I am a tall guy and like my seats all the way back.
69 B-GT
Bill Mertz

I have seen the autopower cage, very good quality and fitment. If you want something better you will have to go "custom" with a race car shop which would charge $$$$.
(The drivers seat can be moved back a bit, while the passenger is SOL, but who cares about the passenger.)

(I have seen the cages for Porsche 911's, 944's, Rx-7's)
James D.

Sounds good, now who knows of retailers that sell autopower cages at a good price?
Bill Mertz

Tony, what do the tophats do? I have seen pictures of them (I think) and I don't really see how they help. Should all V-8ers have these things welded in? Are they only needed in roadsters? (Haven't decided whether to restore my v8 conv. roadster or to get a GT body to transplant the motor to, that's why I ask. Surely it's easier to put them on a shell than onto a finished car?)

There's a couple things I wanted to add to this thread that can strenghthen the shell considerably without much cost, and they are 1. Seam Welding (what road racers and rallyists have done for years) and 2. chassis foaming (which involves filling the hollow sections of the unibody with an anaerobic hardening foam). If I go ahead with my V8 project, I plan on doing both of these as they are cheap and relatively easy (especially if you know how to weld...if you don't know how to weld, I suggest you learn as it's really not that difficult. It just takes some practice)

Ok, back to work for me!

Joe Pitassi
Joe P.

This thread was discussed between 05/11/2000 and 16/11/2000

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