On Tue, 29 Oct 1996 rgb@exact.com wrote:
> So you're the guy?
I'm not sure what I'm owning up to, but "I guess so". I did very well at
that autocross. I was satisfied with my performance, although to be
honest, I think I lost at least 1 sec. due to tire spin. I'll cover that
later on. My best time was a 52.434 that I ran as a fun run after the
competition was over. I believe this run was something like 1.5 seconds better
than the next car in the 6 Cyl. "modified" class.
> How is your car set-up?
At VTR, I was setup as follows:
Wheels: American Racing 4 spokes. 5.5 X 15... stock TR6 width! I had to add 1/4
inch wheel spacers to the front and 1/2" to the rear to get proper tire
clearance with those tires and wheels. Note: the spacers are technically the
only thing that I have done to the car to make it Street Prepared in SCCA or
"modified" in VTR. Really! I will probably settle on 1/2" spacers all around
next year, but I will use longer studs if I do that. This will be just for
safety reasons. Oh, the rear bar puts you in Street Prepared too.
Tires: Hoosier DOT approved racing radials, road racing compound (not
the AutoX compound). 225/55-15. Very sticky!!!
Suspension: Front: stock springs with Spax adjustables on softest setting.
7/8" Addco bar with urethane mounts. The front bushings are stock rubber. Rear:
Moss comp grade springs, the lowest shackle setting (call or write for
details), stock lever shocks with no mods and an Addco 3/4" rear bar with
Urethane bushings on the bar and the shock links, but stock rubber in the
trailing arm bushings.
Engine: Stock with K&N air filters. No header and stock exhaust. The engine was
"refreshed" last year, and I only did some minor port matching for the intake
and exhaust manifolds. The engine is "loose", I did not rebush the connecting
rod little ends. I also have stock original valve guides (cast iron) and stock
valves that were hand lapped into the stock valve seats.
Note: 90K plus miles on unleaded fuel, no valve resession, no wear on the valve
guides (well, almost no wear). I have no idea why this is, but it seems to be a
pretty good setup.
The motor revs nicely up to 5800 RPM's, the stock "redline".
In that config, the car was slightly "tight", that is when I approached
the limit, it would push a bit. Also, I could easily lift the inside front
wheel in very hard conering situations. A real crowd pleaser.
I have changed a few more things since VTR, and now the car is loose, although
I do not see that as bad. What I have changed is that I broke down and put the
Moss comp grade springs in the front. That is all. I really like the new
setup, but I have limited AutoX time with it. Both events that I have been to
since I made the changes were wet ;-(, so My times were slowish due to the
tires being more like slicks than grippy rain tires. I did have some
great spins, though :-0
I would suggest that the front toe should be zero or 1/64" toe in. With the
Moss springs and a tight front suspension, you should probably come out with
1.5 degrees of negative camber, although I have not measured this. I do have
negative camber, though. And I played with the front a lot to get it. If you do
set the toe out, the car is _very_ twitchy on the highway with the sticky
tires. Like "white knuckle" twitchy. Believe me.
My car is very low with the Hoosiers mounted, only 4 inches of ground
clearance on level ground measured from the ground to the frame rail just
even with the rear edge of the mounted tire. I guess that I am about 2
inches lower than most TR6's I have parked next to. This makes a big
difference in handling due to better weight transfer.
For next year, I will probably weld up a differential. With the rear bar, it is
very easy to spin the inside rear wheel with my setup. If I am not totally
smooth, I get wheel spin. This is costing me tenths or more for sure. I would
like a Quaiffe, but my attorney is very demanding with my money ;-(. I will
also probably have Apple Hydraulics revalve the rear lever shocks for a stiffer
setting. Believe it or not, the lever shocks can be okay for AutoX. I am also
going to put on a header and a 2.5 inch pipe all the way back to a single
Supertrapp. With that setup, I should pick up a few "ponies" for cheap money
(relatively cheap any way). I'm going to "jet hot" coat the header.
> I'm building a
> "fun" car out of my '73 TR6, its already been mod'ed by the previous
> owner. I'm adding everything that I've heard of that is known to
> work on the suspension. Engine is another story for later.
My advice is to leave the motor stock until you get the suspension dialed in.
$1000 on Webers is neat, but for $1000 you can put tires and springs and shocks
on the car and be a whole lot quicker than using a stock suspension and a
tricked out motor. Sure the webers look nice, but it's pouring money in the
wrong hole - if you get my drift.
>
> So, what have I missed? Or is it a secret?
I won't hold any info as a secret. Hell, I'd like to see more TR6's at SCCA. In
fact it's kind of a hoot to beat the Wabbits and stuff with a car that's fun to
drive to and from the events. Next year I'm going after the Hondas! I
_never_ trailer my TR6, by the way; most of my SCCA competitors don't
even register their cars on the street.
I might add that JK Jackson covered some of this stuff in Grassroots Motorsports
back in 94 or 95 in an article called "hopping up your XXX on a budget". He
suggests an A type o/d too, and I think that could be a good addition for some
AutoX courses...
One other word of advice: get as much "seat time" as you can. This helps a lot.
When I ran at VTR, it was the 5th or 6th AutoX that I was in this year. I was
really getting a good feel for the car at that point. $1000 worth of seat time
would be very rewarding to better times at AutoX events.
>
> Thanks for any info, I hate to waste money/time on experimenting,
> especially with TR6's, they've been around for 25 years, seems
> most everything should be known by now.
I hope I got you going in the right direction.
>
> Tires, wheels, shocks, springs, suspension mods?
Oh, make sure everything is "okay" before you start making changes! It's a pain
to make the car handle nice and then have the diff mount crack or the front
suspension pickup points break away from the frame.
>
> Thanks,
>
> Roger
> -----------------------------------------------------------
> Roger G. Bolick, rgb@exact.com, (512) 794-9567, FAX 345-2879
>
You are welcome,
rml
-------------------------------------------------------------------------------
Bob Lang Room 11-221 | This space for rent.
Consultant MIT Computer Services |
Voice: (617)253-7438 FAX: (617)258-9535 |
url: http://web.mit.edu/afs/athena.mit.edu/user/b/l/blang/www/home.html
Quote: How many Triumphs do you own??? 3.5, more or less.
-------------------------------------------------------------------------------
|