I agree with Barney on all counts here.
I know that I have mentioned this many times before but, I have installed
negative camber a-arms, 4 wheel spax shocks, uprated springs all around,
everything mounted on poly bushes, and a 3/4 front anti roll bar. If I were
starting over I would go after all of the understeer that is designed into
the rear end. That is by far the biggest hindrance to performance in both
my stock and v8 Bs. The lack of a rear bar with the above setup definitely
makes the understeer more prevalent, but it is bad even with the stock
parts.
It also just occurred to me that the -2deg I quoted was measured right
before I fixed my springs. My first set of uprated springs took a set and
placed the car lightly on it's bumpstops, I have since replaced them and
machined spacers to bring the car to stock ride height, but have not taken
an accurate measurement of camber since.
The rear springs are mounted about six inches lower in the front than in the
back, additionally the roll center of a solid rear end is located near the
axle centerline. Couple that with a front roll center within an inch of the
ground, and you have a heavily overloaded outside front tire when cornering
hard.
IMO that understeer and the imbalance in roll centers are the most important
things to fix for a real performance car. However, I don't know of any off
the shelf solutions for those problems at this time. The closest thing
might be a rear anti roll bar but I haven't had a chance to try one yet.
James Nazarian
71 MGBGT V8
71 MGB Tourer
-----Original Message-----
From: owner-mgs@autox.team.net [mailto:owner-mgs@autox.team.net] On Behalf
Of Barney Gaylord
Sent: Wednesday, May 26, 2004 10:52 PM
To: Paul M.; Don Vierling; mgs@autox.team.net
Subject: RE: steering rack alignment (now shock and camber shimming)
At 01:10 PM 5/26/04 -0700, Paul M. wrote:
>....
>In addition to the resulting negative camber, I'd be curious to hear what
>people think of the value of these arms as a modification. When you lower
>the car with the springs, it goes negative anyway. How much negative
>camber is too much?
When the handling starts to degrade instead of improving, or your tires
wear out in a few thousand miles, it's too much. For the normal daily
driver street machine, anything other than original factory spec of zero
camber will result in increased tire wear. The only reason for going to
negative camber is for competion, and then you have to accept the trade
offs for street use.
I can tell you that the front tires do not like 1 degree negative camber
when driven long distances on the street. They would have bad wear pattern
on the inside half of the tread width, maybe shortening useable tire life
by about half.
Barney Gaylord
1958 MGA with an attitude
http://MGAguru.com
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