Front Suspension Bush replacement

[Graham Dix]

I have recently replaced my front suspension bushes having been horrified at the deterioration of the ones fitted just six years ago. See photo. I have always tried to maintain originality but the poor quality of available rubber these days seems to make sense to look for better options. I settled for replacement poly bushes from Autobush.com that are dark blue in colour and thus hard to notice when fitted. These are reasonably priced and once fitted have drastically improved the rigidity of the front end. Very impressed. Graham Dix

[Peter Cresswell]

Part of the problem relating to the front bushes deteriorating like yours have, is down to the grip modern tyres can generate, this being much greater than the crossplys the bushes were designed to cope with or even the radials of the 1960s/70s. The other part of the problem is down to poor quality as Graham suggests.
Although polybushes are good (I use the dark blue ones as well!) they do induce a degree of harshness that is not present with the rubber bushes, and RV8 ones might be a good alternative. I also believe V8 ones are rubber with a steel sleeve.
Incidentally if you look at the angle of the front wheels from the front of the car (like in my avatar on the right) and they are at different angle on each side (the camber angle) either positive (they lean out at the top) or negative (they lean in at the top) you can correct this using bushes with an offset hole. They are available from B&G but were out of stock when I enquired recently and I haven't seen them listed elsewhere. Part number is 8G6210/S and come as a set of 4.

[George Wilder]

Pete and Graham
I have been using V8 bushes in my MGB front supension for years and years - it was a standard mod years ago.

Last for years and years

[Peter Cresswell]

I always meant to come back to this thread but I needed a mental prompt in the form of the summary of this thread in the recent issue of Safety Fast!
During our recent Summer Tour (August 13th) the rear wheels suddenly started rubbing on the wheel arch again on tight hairpin left bends and through the day this got progressively worse. On stripping out the shackle bushes on both sides I discovered the two outer ones on the drivers side of the car had started to break up, much like early stages of the picture posted by Graham above. These were RV8 ones fitted about 3 years ago, and have now been replaced by blue polybushes from B&G in a further attempt to keep the axle in check. At the same time I ordered a set of the off-set top trunnion bushes (8G6210/S) for the front to as these were showing signs of wear and I have wanted to get the camber the same on both sides for some time. The rears were relatively easy to install other than the closeness of fuel tank on one side and the rear silencer on the other gave restricted access. But the off-set front bushes are nylon and very difficult to compress. Plus of course I had to measure the camber angles I had accurately and decide on the angle to set the wheels at. On the nearside the worn out top bushes gave about 3/4 degree negative camber and on the off side it was 1/2 degree negative. After some research I decided I would aim for 1 degree negative camber on both sides, which after some fiddling about I have managed to get. You have to be prepared to take the bushes out a few times to turn the round a little more or less to get it right. You also need to measure the car when it is perfectly level front to back and side to side, and having a sloping driveway didn't help! With the aid a of a metre long spirit level, a long piece of angle iron and some blocks of wood I managed to make up a flat surface and I did all the measuring using an ADA Camber Caster gauge I used to use whilst racing. See http://www.jjcraceandrally.com/karting/ ... mber-gauge for an example of one of these.
The result is the steering is lighter in straight lines and gentle sweeping bends, and loads up as the lock is increased. This is because the loading on the tyres has been pushed more onto the inside edge of the tyre and less so on the outside edge, plus with negative camber the angle the wheels adopt in a sharper corner is the sum of the camber and the caster angle at that point in the steering angle, so you get more camber as the steering input increases. I will need some photographic evidence to see if the goal of keeping the front wheel on the outside of a bend vertical through a turn has been achieved.
I should add that I like the sharper turn that negative camber gives, but this might not be for everyone!