[Fot] Suspension modifications

[Bill Babcock]

Here's a hint that goes along with this. When you want to adjust the heim
(rose) joints just remove the two bolts that hold the upper arm to the ball
joint and turn the arms in or out to adjust. I'm still embarrassed about how
long ti took me to figure that one out. I was disassembling half the car to
make the adjustments.


-----Original Message-----
From: fot-bounces+billb=bnj.com at autox.team.net on behalf of Bill Babcock
Sent: Mon 12/24/2007 12:01 PM
To: Jack W. Drews; Fot at autox.team.net
Subject: Re: [Fot] Suspension modifications

I don't run this modification on Peyote, but I did on my cheater TR3, and I
probably will add a version of it to Peyote this year.

I made a 1/4" steel plate that holds the pivot point using two countersunk
screws to hold the rear of the pivot to the plate. The front pivot bolts go
tthrough the original back pivot holes, and the front of the plate bolts to
the original front pivot bolt holes. This moves the pivot back the width of
the pivot bolt hole spacing--about 1.6 inches as I recall. According to
SusProg it's too much, but it's easy to do and it works pretty well. Most of
the force against the pivot pushes the plate down against the shock towerr--I
never had even a hint of bending or other problems. In fact I forgot to fully
tighten the countersunk bolts once and didn't have any problem. Many years
ago
I recall seeing someone run a TR3 with the pivot moved back and only bolted
on
the front side through the rear bolt holes--same idea but a much scarier
approach. In fact it was the inspiration for my modification.

You need to make the upper arms longer to clear the shock tower and give a
proper amount of camber, so it makes sense to convert to rose joints and have
adjustability. With the stock arms you'd have about four degrees of camber,
which is too much for our semi-radial tires. I'm a bit fuzzy on how I set
that
up, but I recollect it was 3 degrees with Comp TA tires and 3.5 with Yokohama
A008's. With the arms set for bias ply tires (0 to 1 degree) I had about two
degrees of camber gain at full bump (according to my sketchy notes).


-----Original Message-----
From: Jack W. Drews [mailto:vinttr4 at geneseo.net]
Sent: Mon 12/24/2007 11:30 AM
To: Bill Babcock
Subject: Re: [Fot] Suspension modifications

I agree with everything you've said about the camber change, the
excess at full limit, small contact patch at high camber angle, and
the advisability of leaving the upper a-arm at least as long as stock
-- maybe longer is even better. I'd like to modify my car as you suggest.

Last winter I spent some amount of time trying to figure out how to
do that and was not successful in figuring it out. I have one photo
somewhere of one of your cars, Peyote I think,  that looks like the
new attaching points are on brackets welded to the front and back of
the tower and braced at least in the rear to the diagonal brace to the rear.

My problem was trying to figure out how to do that on a car with
stock bodywork without removing the body.

Any suggestions?
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