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Posted by: brant May 24 2022, 11:27 AM

A week back, I attended a vintage race in colorado
the car did fine... the driver was slow, but still had fun
a couple of shots

I ran a staggered set of bias- ply vintage tires... car was not aligned for them... and they were a bit underwhelming...


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Posted by: wndsrfr May 24 2022, 11:42 AM

Tough to get enough meat on the track on a non flared setup. What age were the tires, what sizes...looks like 15 inch rims...

Posted by: johnhora May 24 2022, 12:00 PM

"Driver Slow"....Nothing like the first race of the season to get the cobwebs out of the ole driver and with a new setup added to the mix...You look good buddy...have fun this season!

Posted by: brant May 24 2022, 12:02 PM

I'll have to pull the sizes.... the hoosier TDR tire in 15inch
a year or more old... just wanted to run them for a full event and see if I could adapt.

I can get 8 inch fuchs under the back easily
but class restricted to 7inch rims.
typically run a 225/15 on 7inch rims with a 1 inch spacer for track (because I have the room)

I only ran a 3/4 inch spacer on these... due to the balloon sidewalls.
fenders are modified....just as wide as a flared car

plus this is a low HP 2.0 motor so plenty of traction in a straight line.

Posted by: wndsrfr May 24 2022, 04:35 PM

I'm on 15's...Hoosier TDR 7.5-23-15 front and 8.5-24-15 rear. Start at 17psi finish at 22. Car is faster than the driver which is a good thing....I think??

Posted by: brant May 24 2022, 04:47 PM

You motivated me to go to the trailer
Same size and tires front and rear as you

Thanks for the input on pressure
I think I was at 19psi

Sunday afternoon I got frustrated with the tires and put on a 6-7 year old/45??? Heat cycles. Set of 225/15 A7 tires and pulled a half second off my times

Just having a hard time liking them
They recover well from small slides. But they slide way to easy at turn in

What did you do for alignment numbers? With these?

I tested them for one day last year and went back to the speedsters
Decided it was time to give them a second chance…. But still not loving them

Wish I had dropped the pressure in hindsight

Posted by: GregAmy May 24 2022, 08:41 PM

I run Hoosier A7/R7s on my "regular" race car but most historics groups don't allow them.

I've run Hoosier Speedsters on my historics 914 ride and I just don't like the tread squiggle.

So my recent "go to" has been Nitto NT-10 DOT 100TW tires. They're a good construction, very responsive, and wear nice.

I'm moving to Conti 200TW DOT Extremes. Sure, they're not as fast as A7s (or possibly even not as fast as Nitto NT-01 100TW) but I'm a Hoosier butt-boy and I think they're a good choice. After all, this is historics racing, not LeMans.

For comparisons of radial DOT tires versus "radial slick", we've tested Hoosier A7 245/40-17 and 265/630-17 M compound Hoosier same weekend (the "real" race car) and I honestly did not notice a significant difference in lap times and/or driving characteristics. I wish I could have tested them blind but I'm the one that had to swap the tires, so...

I personally don't like the way bias-ply slick tires drive. I've found the 914 chassis to be much more responsive on radials, with less slip angle required and a lot more total grip. But note I've been racing on DOT radials since the 80s, from Showroom Stock through various iterations of touring cars.

I find the DOTs easier to drive and easier to set up the car. But of course that's a personal preference. - GA

Posted by: ValcoOscar May 24 2022, 09:14 PM

QUOTE(brant @ May 24 2022, 10:27 AM)

Posted by: wndsrfr May 25 2022, 06:38 AM

I'm at just under 2 degrees negative both front and rear with about 1/16 inch toe in. I'm no expert but watch the edge wear and temperature profile to decide if change is needed....

Posted by: brant May 25 2022, 08:59 AM

QUOTE(wndsrfr @ May 25 2022, 06:38 AM)