experiments with scrub radius.
so the front end is less than perfect with the 245s on the front and a really positive scrub radius its pretty twitchy.
i couldn't get the wheel any closer to the strut, its basically touching now. i started thinking about the clevis type mounting of the strut that lots of modern stuff has. that design would allow me to move the wheel inboard and decrease the scrub radius right?
so, choose one that has lots of parts available and is really well supported by aftermarket shit.
S15. parts for days.
so i bought some S15 front hub carriers and LCAs and had a bit of a measure. straight away its clear that the Nissan design moves the ball joint 30mm closer to the centre line of the tire. whilst all other things remain basically the same. win.
on first inspection it looked like it could work. there were a couple of things that might throw a spanner in the works but i rang the guys at Techno Toy Tuning and they could supply me with a fabricated lower control arm that would bolt into the AE86 crossmember and have the right balljoint taper for the S15 hub. good.
so with a bit of fucking around i amassed the following parts that in theory would all come together seamlessly to make it work,
S15 Tein coilovers
MX70 cresseda inner tie rods
TTT LCA's made to adapt S15 to celica/AE86 (ring them, they make heaps of them apparently) complete with castor arms
stock S15 tie rod ends
bolt it all together then attach it to a celica and it all fits.
bump steer measured at +2mm from ride height to full bump and + 2mm from ride height to full droop. a total travel of 140mm and a total toe change of 2mm positive. that will do me just fine.
have i fixed the scrub radius?
well its all theory at this point because i only trialed it today. i need to get the struts rebuilt and find the bracket that came with my front brakes that will bolt my calipers to the S15 hubs.
the ball joint is 30mm closer to the centreline of the tire.
at 2 degrees camber the strut top is much closer to the center of the car that it was before. when you draw it all that change in line angle makes a big difference.
also there is now a 20mm gap between the strut and the wheel so i could move the wheel in by 20mm and decrease the scrub radius even further if i need to.
im calling it a win. im going to get the struts rebuilt and find the brackets then bolt it all in and see what happens.
here are some random pictures of things.
2017-09-30_04-59-07 by sheepers, on Flickr
2017-09-30_04-58-57 by sheepers, on Flickr
2017-09-30_04-58-39 by sheepers, on Flickr
2017-09-30_04-58-30 by sheepers, on Flickr
2017-09-30_04-58-21 by sheepers, on Flickr
2017-09-30_04-58-05 by sheepers, on Flickr