Hello All
Still working on getting some photos up of my MGB V8 Roadster 4.2 Rover .... only put 700 miles on it last summer ..... build was by a fellow in southern calif. ..... It was his second conversion of a "B" with a V8 conversion ... I bought it last November and I am still sorting out what I have - but overall a very sound build ..... a question .... how strong is the MGB Shell? Is the GT shell considerably stiffer? I have enjoyed alot of reading on this superb site and never hear any discussion of twisting or deflection of the shell ,,, is it a non-issue up to a certain horse power range? I have seen some high horsepower MGB's that add a sub frame or tube frame ... but what of the MGB shell for us run of the mill 250-300 hp guys....... any thoughts?
A related question ...... I have been underneath the car ..... just seeing what I bought ...Is it perfectly save to have the front jack stands under the " frame rail" just before it curves up into the engine bay? Is that a good point to support or do I need to go under the front suspension? Want to make sure this would not stress the shell ..... Back stands under the axels
Alan
Boston Mass
Jack stands under the frame rails are fine. I put mine there sometimes. Under the front suspension is good too. (although if you're dropping the rear suspension for some reason, I'd probably put them under the front suspension -- not sure if the weight of the motor would cause the car to tilt if supported behind it w/o the weight of the rear suspension to counter balance.
With a 4.2 Rover you're probably well below 250-300 rear wheel HP. Most V8 MG's that aren't regular drag stip cars either have no chassis stiffening or just a piece of rectangular tube from the middle cross member back to the spring perches. Some seam weld but that doesn't seem to be needed even with the Ford 302 & Chevy 350 swaps that have been done (which are likely higher HP & torque than the Rover). You might contact Pete Mantell; he has a 347 (302 stroker) & drives it pretty hard on the track -- he could tell you if he's seen any need for more reinforcements.
Alan,
After a full rear clip replacement on my B "tourer" and copious amounts of metal repair the MGB tub is a very well engineered monocoque chassis!
The frame rails are strong enough to hold up to a v8 with no problem, it is the way the inner fenders tie into the frame rails and into the rockers, making a very strong truss through the car as is the trans, driveshaft tunnel.
The rockers are the strongest truss in the car, being a double box, sandwiched with an 18 gauge stamped plate front to back inbetween.
Plus what Rob said!!!