Whilst all this wing malarky is going on I am of course driving the old rust-bucket every day and particularly enjoyed the recent DDK meet up in north yorkshire - with some excellent driving. If you were up there at the time you'd have heard my front suspension - the word 'creaking' doesn't begin to do justice to the cacophony of noise that erupted every time I went near a bump. My suspension's generally been good but a bit squeaky when I haven't kept up to date with the greasing (I've got elephant racing bushes all around)
In particular I noticed that after a vigorous trackday it would be more creaky - but then when I greased it up afterwards the noise went away.
A couple of weeks ago we went on holiday and the car sat unused for a week. When I drove it after that the creaking had become a bit of a monster. Having visited center gravity on their charity open day last year I gave them a ring. Chris was very helpful and I booked the car in. He let me bring it in early because I was nervous about what sort of damage I might be causing - I could bring it in early and they could fit the squeaky job in between other jobs. So I took it in the Monday after the North Yorkshire meeting and collected a hire car from him.
When I got there I'd just dropped right as he'd finished a test drive and had a bit of time to spare. He offered to strip it whilst I was there so I could see it for myself. It was really interesting.
I'd previously established that the squeaking was coming from the rearmost bush on the drivers side of the front suspension - so just under/near to my feet. When Chris finally got it off we found that the inner race had fused itself to the outer race, and taht the JBweld holding the inner race onto the A-Arm had failed - so the creaking was that inner race rubbing on the A-Arm.
Separating the two races was a bit of a job, even on the bench
It took a 10-ton press to push it out. When it did come out it was clear the inner race had corroded (not massively) and the expansion involved in this had jammed it inside the outer race - eventually to the point where the JBweld was the weakest link and had to say goodbye
Looking inside the outer race (which is bronze) I was surprised to see it was more or less in perfect condition. The grease channels were blocked with old grease but other than that it was perfectly fine. I must admit my greasing of the bushes had been sporadic - and once the grease in the channels has dried out it blocks the new grease coming in and the problem gets worse.
Chris had a word with an engineering firm around the corner about turning a new inner race out of stainless - but the guy said that it had to be so thin that the stainless would have been too brittle. They found however that putting it in a lathe and applying a bit of emory cloth removed the corrosion very quickly (i.e. it didn't take much removing), leaving a very usable race. The race originally had some sort of coating on it and that has disappeared so it's not ideal, but as a solution that got me back on the road for not a lot of money I went for it. If I keep it well-greased in future and also devise some sort of boot for it held on with cable-ties I reckon I'll have quite a few more years out of it.
When taking it apart it became clear that the front ball-joints were shot so Chris replaced those. He then put it all back together and set the front up for ride height, toe-in etc. As he put it together he removed a couple of spacers I'd previously put in which I thought were aligning it properly (they weren't)
I picked it up yesterday. Chris was very complementary about how the car drives, describing it as a real outlaw. For the test drive he started by taking me round and round a roundabout at speed - the cornering speeds surprised me and I felt sick coming off it. He then took me on a series of country lanes showing fast smooth corners and tight bumpy corners and everything in between. He showed me how it now tracked exactly as it should do - gently following the camber in the road. We then swapped drivers and I had a go. It definitely felt better than it had done before (although it did feel pretty good before). It was hard for me to say for sure as I didn't know the roads and I'd got Chris sat next to me. I said I was thinking of doing the whole setup thing and Chris said the car is driving so well he wouldn't bother. It would be a benefit but it was so close now I wouldn't feel a massive benefit. His honesty really impressed me.
It was really nice for Chris to be so complimentary about how the car drives. I felt it was good and I really enjoy it but I've got no frame of reference - I've only driven one other 911 properly.
I got it home last night and went on a road I know really well. It is MASSIVELY more sure-footed. There was a dual carriageway with a bend - I used to go round at about 75 and it felt squirrelly - not massively so but a bit disconcerting - enough to make me not want to go much faster. That had completely gone - it felt rock-solid and planted at 85-90. Later on going around righter bends the front just felt gorgeous - smooth, planted and confident (much like myself). Chris said the ball-joints would have contributed to the fast-corner nervousness as they'd have been fidgeting the wheel around the long bend.
I'd commented to Chris that whilst I loved the LSD I installed over a year ago, it robbed me of some front end turn-in. Chris suggested I tightened up the rear anti-roll bar to bring that back - so I'll give this a try over the week-end.
Chris and all at Center Gravity have been a real pleasure to deal with. Chris himself is a real enthusiast and is really passionate about these cars - he's currently building himself a track-focussed impact bumper car, and every time I go there I see at least one GT3. I can't recommend them highly enough. I've no connection with him or the business.
