Rstr7 Wishbone Castor

[Guest RH CAT 7]

i have a early robinhood rstr7 and i think the top wishbones are on the wrong way round, it seems to have positive castor , ie top of upright is forward of bottom tca center line when looking side on. any ideas?

[Bob Tucker]

Hi I dont know the TR7 based hood, but any car needs to have +ve castor, ie the top pivot point must be behind the lower one.

This is so as the wheels turn, they effectively lift the car up, the cars weight then tries to force the wishbones back to a straight ahead position.

Without it the car wont self centre & will wander like a drunk camel.

Put the wheels on some glossy magazines.....your choice!!....measure the ride height exactly...have someone turn the wheel to full lock & re-check the height...it should be higher....I cant tell you the right figure for your car tho'. You could also use a plumb bob to determine the setback amount.

HTH Bob

 

http://en.wikipedia....ki/Caster_angle

[Peter Bell]

Pictures are needed, can you post some? TR7 that must be a rare one, I think the dolomite version just used the donor front subframe.

[Guest RH CAT 7]

there is a good picture of it on page 10 of items for sale on here, its listed as rstr7 chassis unfinished project. i may have got it wrong saying + ve castor, looks like its - ve castor,but as i said the top of the upright/balljoint is way forward of the lower joint. you cannot push the car as its got a mind of its own and will not turn, i think the wishbones have been put on the wrong sides!!

[Bob Tucker]

That looks possible from the pictures.

Simplest is to measure the distance from the ball joint to the front of the wishy then to the back of it.

Fit so the longest part is to the front of the car.

HTH Bob

[Snapperpaul]

I'm not happy with the steering rack position.

The track rods look a longway forward

First step would be to compare the hub and steering rack position with the donors factory setup