The problem with the worm and peg is that it gets vague very quickly. Under
normal street use it gets notchy relatively quickly. You have a small peg
being pressed very hard into a small diameter worm notch. There's a lot of
wear and wiggle.
The Revington kit looks good, but I think it's rational to gin up your own,
like Peyote's. There are a lot of nice narrow Japanese racks in the
junkyard. A little time in the lathe removes all those strange names, like
Isuzu, and makes nice clamping areas for a set of aluminum mounting blocks.
Then you can shim the rack up or down to fiddle with bump steer. If you
like I'll send you a picture.
-----Original Message-----
From: owner-fot@autox.team.net [mailto:owner-fot@autox.team.net] On Behalf
Of David Talbott
Sent: Thursday, July 28, 2005 9:43 AM
To: fot@autox.team.net
Subject: TR 3 Steering
Speaking of rack and pinion options for TR3's, does anyone have any
experience with the Revington kit? From what I've seen and read about them
on-line, they seem to say all the right things with respect to minimizing
bump steer and adding some Ackerman effect, and it appears to be a very
sturdy weld-in affair. With my current bare metal frame now would be the
time to do it, however, it is a fairly irreversible step, and here in the NW
these kinds of modifications are typically frowned upon. It also seems to
me that the geometry and bump steer issues are much a function of ride
height, and the Revington folks appear to be very focused on rally
preparation with the obvious requirement of much more ground clearance than
a road course car.
I continue to question the basic need, not to mention the measurable benefit
in terms of lap times. I'm hearing lots of positive responses from those
who have made conversions with various components, but I'm having a hard
time comprehending how the worm and peg could be quite so bad, especially if
it is maintained. I'll admit that my prior TR3 racing experience is many
years past, but I don't recall a great revelation in steering when I moved
into a TR4. Sure, they are hard steering and awkward around the pits, but
aren't
most race cars, especially with locked diff's? It seems to me that the
steering in almost anything gets pretty light when you're going fast, so the
question becomes are you steering or herding? I'm also a strong believer
that one learns to drive around most of this kind of stuff anyway, realizing
that may not be the fastest approach, but I try to remember that we are
talking vintage here.
I think I remember Hardy having added a TR4 rack to his TR3, based on the
same logic as Joe B., i.e. the cars are on the same page of the SCCA PCS
book, although I'm sure that came about in a much later edition than the
usual 1969 cutoff date for most vintage rules. If you are listening Hardy,
maybe you could chime in on this. As Damdinger said however, every such
change just makes it that much less of a TR3.
On the fence in Oregon,
Dave Talbott
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