Originally Posted by
Govert
Did you guys ever think of "forcing the suspension blocks to one side"? By that I mean, when you mount a screw in the suspension block, the block will move according to the direction you are screwing. So, clockwise. The suspension block will wander clockwise as well when fully tightening, not (always) noticable by eye. This is completely normal. I even have this on my Xray T4 and previous Capricorn and Tamiya cars.
You should move/hold/force/press the suspension block counter clockwise when tightening the screws, in order to keep it in place and not messing up your toe value. This is completely normal for blocks that do not have the centering posts, like Tamiya has.
If your car has more toe in on the right rear wheel, let's say 1 degree more than the left rear wheel, you need to correct it with only 0.5 degrees. Seems a lot, but it isn't. Loosen all the suspension blocks of the rear suspension, (in this case), tighten the screws from your RIGHT RF block while giving pressure towards the screwing direction. This will reduce toe in on your RIGHT side. To increase toe in on your LEFT side a bit, do the same, tighten the screws of your LEFT RF block and give pressure towards screwing direction. So now, by doing this you have reduced right rear toe in and increased left rear toe in.
Finally, do the same with the RR block. Press it counter clockwise, against the screwing direction, when tightening screws. This will again decrease right rear toe in and increase left rear toe in. As a result you will have equal toe in.
On some cars the chassis holes can be drilled a bit wider or could have worn out a bit, causing the suspension blocks to move when fully tightened. this will screw up your toe value.
Also, what I would always do, check hinge pins as well and rear hubs. Make sure these components are ok. If they are sanded or modified in any other way, just check if your method could not have influenced the toe value in any way.
Third thing: some bearings are not always ok. They give some slop on the axle, causing the axle to move a bit to one side or another. So when you attach the setup system, the slop between axle and bearing will actually cause the toe problem.
Also, detach the setup system and relocate it. Spin the wheel axle a bit and attach the setup system while putting pressure on the setup board, because, just like the suspension blocks, the setup system can also wander off a bit when you thighten the wheel nuts.
I have owned an Integy setup system for years, now I own a Hudy. Much better and much more accurate. But that is some other thing.
Make sure wheel hexes are ok, no debris behind the hex and pin and fully screwed on without any binding problems or any other problems.
Just take good care of the suspension blocks when tightening them. You can ädjust the toe value "by hand" in this way. I am quite sure this will help.
Yeah, done that
That was my initial suspicion.
I thought I put the car together wrong, so the second time I just did the screws finger tight (all four) and placed a piece of square tool steel along the two blocks, across the chassis and tightened the screws in turn, one half turn at a time. This method has always produced perfect results, aligning the blocks with each other and pulling the blocks down evenly between the screw holes.
Play/slop (in bearings, suspension, etc) has no impact I suspect because it develops evenly (why would one side wear more than the other anyway?). Either way, all my cars wear out but the toe readings are within the same range left to right (they become a sort of range rather than one value, but as long as the range is the same left to right, the car is fine).
And as you say, forcing one block sideways when tightening the screws is going to help, but this is just a band aid. Take even a small hit and the block will "slip" back in the "normal" resting position (i.e. where the screw heads rest centred in the countersunk section of the holes). I did this too, but just didn't feel right and long term is a hassle. It didn't manage to fully correct the problem either. There was still about 1 deg of difference in toe (left-right) because the holes don't allow more room to jiggle the screws around.
I think the best system (well, manufacturing defect-proof) is still the one used by Xray some time ago with the shims. That way, you can have the holes out by miles and still bring the toe back true.