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MG MGB GT V8 Factory Originals Technical - Poly vs Rubber Suspension Bushes

Seasons Greetings to all,
My V8 project (1970 B undergoing full restoration), is getting 600lb front springs with 3/4 anti-roll bar and uprated dampers. Problem is that I don't know whether to go for poly bushes all round or stick with the softer rubber (V8) bushes etc.
Can anyone help with personal experiences? My car is not going on the track, just the odd bit of fast road work. TIA,

Stainzy
Stainzy

My cars have standard V8 inner wishbone bushes, standard metallastic front eye bushes on the rear springs and all the rest are poly. Brown and Gammon do a really nice set all round. In the US, Suspension Restoration in CA do a nice set of Energy poly bushes for the B with nice lubricated a/r bar items. I should forgo the 600 lb springs if I were you and fit standard late r/b units. Ron Hopkinson will fix you up as can many others.
Happy New Year
robert pulleyblank

Thanks for that Robert, I might give Ron Hopkinson a call. I have been talking to Brown and Gammons so far and although they advised me to go for 8 inch springs, I wanted to go for 7.5 or 7.85 inch because I have used a R/B front cross member and want to lower it slightly more. Problem is that the 7.5 and 7.85 springs only come in 600 lb.
Stainzy

Poly bushes, 3/4 roll bar and 600lb springs your car will feel like a go kart.
Great for fast road driving but you'll get sick of being rattled around pretty quick.
Hope youv'e got good strong teeth.!!
Leslie Cole

My experience:
Early in my conversion I rebuilt the whole suspension with new stock rubber bushes from Moss/VB/TRF. I was shocked to discover a year later, the car not even having been driven yet, that the bushes were already dry rotted and crumbling. I can only guess that the parts I received are not up to OEM standard for rubber quality.
To fix that problem, I redid everything with poly. But not just any poly. You have to be careful in the these discussions as poly from various sources can be wildly different in hardness, depending on the intended use. I found that the red colored "Prothane" polyurethane bushings as supplied at the time by Moss, are just about the same hardness as rubber, but should be MUCH more durable. I have all Prothane including crossmember mount pads, rear spring pads etc, with standard V8 bushes on the lower arm, 3/4" front sway bar, 5/8" rear sway bar, new Armstrong shocks with standard valves, 1" lowered front coils (red w/ blue stripe), and 1" rear lowering blocks. 185/65-15 Dunlop D60A2s on Minilite copies. The ride is actually quite nice, not harsh or noisy at all, and the steering response is firm and quick, not twitchy or go-cart like at all. I am very happy with this setup, it's pretty conservative I think for a daily driver that is only occasionally used to intimidate and frustrate Mustang drivers.
Scott Pontius

Oh, sorry, '78 roadster, rubber bumper, SD1 V8/LT77.
Scott Pontius

This thread was discussed between 29/12/2000 and 31/12/2000

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