quattro Digest, Vol 5, Issue 87 - 4KQ Spring Chop (long)

[l.leung at juno.com]

Be careful with the generalization. On cars that roll excessively
(VAG of the 70's - early 90's, including the 4KQ of the subject) the roll positive camber change can (i.e. roll of the car is so much that the front of the tire tips away from the turn) exaccerbate understeer. 
Stiffening ANYPLACE on these cars against roll can combat the roll positive camber gain enough to actually reduce understeer, EVEN IF THE 
ONLY OPTION IS TO STIFFEN THE FRONT. In SCCA Solo 2 Stock class, the only anti-roll bar option is a front sway bar, at this point, you can't even change the camber past alignment +/- specs. I stiffened the front
end of an A2 GTi (sway bar) and got better turn in, more grip, and even tire temps on longer (divisional/tour) courses which resulted in decreased lap times on fixed courses (go cart tracks). I could even get the rear to come around on trail braking after the mod. The resultant mod worked very well in terms of my competitiveness during the seasons I ran the car, which ran from the mid-80's right up until the car's untimely in storage destruction in the late '90's. I do miss that car, and the many, many seasons of competitive success even against newer iron. BTW, shock adjustments simply adjust the transitional response, they really don't have much effect upon steady state cornering (unless they are so bad or worn that the car is bouncing through turns).  

So, the rule stiff front increases understeer, stiff rear oversteer does work, AS LONG as the car is already properly set up. I beg to differ with the supposed understeer would get worse on a stock 4KQ (although I would NOT recommend cutting the springs due to the end coil diameter seating) with stiffer front springs. Other changes to the geometry may be at issue (really need to watch the camber changes as the car is lowered) but those generalizations must be stated with conditions. 

LL - NY


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Date: Mon, 22 Mar 2004 06:16:48 -0600
From: Hoffman Anthony J A1C 552 CMS/MXMVC
	<Anthony.Hoffman at tinker.af.mil>
Subject: RE: 4KQ spring chop
To: "'Jason Gray'" <jason510 at att.net>
Cc: "'quattro at audifans.com'" <quattro at audifans.com>
Message-ID: <200403221218.i2MCIwb0019222 at legolas.tinker.af.mil>
Content-Type: text/plain;	charset="iso-8859-1"

Just to correct, Stiffening the front of a car relults in
understeer(pushing) and stiffening the rear results in oversteer(tail
sliding).
Tony Hoffman 

-----Original Message-----
From: Jason Gray [mailto:jason510 at att.net]
Sent: Wednesday, March 17, 2004 2:15 PM
To: quattro at audifans.com
Subject: 4KQ spring chop


Cutting stock 4kq springs is a bad idea. The ends of the spring are wound
with smaller diameter than the rest of spring, removing part of the pigtail

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