Reply With QuoteUnpleasant straight ahead.
anyone shed any light on this upgrade?Originally Posted by strat24v
Unpleasant straight ahead.
The split alloy bearing is just two halves of a block with a semicircle cut out such that it clamps around the intermediate column and is bolted to the chassis. Sometimes it's a little tight and just grips the shaft and restricts it's ability to rotate. There are two alternatives that I've seen. First involves splitting the intermediate shaft and sliding a standard bearing over the shaft before re-welding the UJ back on. After that's done you need to make a suitable bearing carrier and support. The alternative involves splitting the shaft and fitting a Rose Joint and re-welding the UJ. This is the simpler solutions the threaded Rose Joint gives you a lot more adjustment height wise and almost as little restriction as a full bearing. Unfortunately RHD cars can't do away with the intermediate and adaptor shafts as the column routing falls between the brake & accelerator so it has to stay high to avoid feet fouling it. LHD cars can have a lower column route as the shaft passes between the brake and clutch pedals.
If you can measure your intermediate shaft length between the two UJ's I'll compare it to a spare I have here that has a bearing fitted already if you decide you want to try that mod.
Guy
Car steers straight with no hands, just sensitive to hands!! Ie no Ackerman effect.....
Guy I have just checked and have the split alloy bearing but it is fine and not providing any issues so I think I will pass on any work here.
Guy, what were your car's symptoms before you decided to wind on a lot of castor? Do you now have good self centering, or just a little bit or none at all? Did you find you had a bump steer issue with so much castor? I assume by the name, bump steer means the steering is affected by bumps??
Hi Tim, the first thing I did when setting up the car was wind on as much castor angle as I could get away with. The tyres just clear the bodywork on full lock/compression/droop. The first time I drove the car there was some self centering which improved as the mileage grew. (I'm back to some now with the new LHD rack but expect it to ease as the rack beds in). The first time I drove it the bump steer was terrible. I got as far as the MOT station and back. At which point I stripped the shocks off and set the rack height to eliminate the bump steer. Easy enough to do but time consuming. And essential if you want to be able to relax, relatively speaking, behind the wheel.
The symptoms of bump steer are finding the the car darts to one side if you hit a pothole or a bump in the road. It can be quite violent and you'll know if you;ve got a problem with it already! I'd be amazed if it hadn't been dialled out at build or by Gary during use.
Guy
Going in the garage and twiddling the steering wheel and reporting no issue isn't really a way to solve you're issue. Rather than listening to tales of other people's wonderouss car building skills, I'd be inclined to forget them, go back to basics and eliminate all issues others besides myself have mentioned. I have only seen two professionally built models in all my time that I'd consider good enough not to have to strip and start again.
Guy thanks for this. I need to do more miles but today showed very good stability, even over bumps. Maybe the twitchy feel compared to my other Lancias goes with the territory. I am looking again at the front end and am measuring everything. This is a well put together car and nicely developed by Gary that I am proud to continue its refinement.
thanks to other contributors too as all experience welcome to add to the theory.
Slightly off-topic but there is a nice description of bump steer and how to try to dial it out in "Project Binky" episode 10 (around 23 mins onwards) and continued in episode 11, where they also go into some detail about "Ackerman" - I see that you mentioned this above so maybe you are already aware. If not - be warned! - and be prepared to invest 5-6 hours of your life watching all the episodes (addictive viewing I find).
Change of header title!!!
Just finally got Shades off Castor / tracking gauges and out for a test run
Transformed!
2mm Toe in Front
0.2 degree Toe in each side rear
4.5deg Castor front
-1.1 camber front each side
-0.4 camber rear each side
Ride height 15mm higher rear to back
Front tyre pressure 20psi
Rear 22psi
Steering slightly heavy at parking speeds but lightens up and has the twitchyness at speed has gone. Roads are too greasy to explore handling at any limits but I have a big grim on my face as IT IS SORTED!!! AND I love driving it!!!!
This is just a base line and in due course I will put it on laser rig to check my measurements done mostly with digital protractor set up.
I think the biggest contributor to getting to this point was to increase the castor on the o/sf which was a shade over 1.5 degrees before adjustment. I have yet to find any bump steer issues so conclude this was properly set up by my predecessors.
Posting Permissions
Bookmarks