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Posted by: ThePaintedMan Aug 22 2014, 12:13 PM

Well I continue to learn more every day. I was always under the impression that even track cars have their tires balanced. I specifically remember seeing wheel weights on the rims of GT3 Cup cars at Sebring. But apparently a lot of people think it's a waste of time and energy to balance them since the tire moves on the rim in high-G corners, lock ups, etc. What say you, o 914 racing veterans?

-G

Posted by: Jetsetsurfshop Aug 22 2014, 01:15 PM

No veteran here, but heres what i've learned.

My tires do not move at all on my rims. I marked them to check.
weight of car 1987lbs (without driver)
brakes 911m calipers with hawk dtc-70 all around.
HP we think about 150

Now, on my friends vette they just balanced the rims only. The tire moves on the rim for sure. I also have never been in a car that stops that aggressively.

Maybe the GT3s are doing like my friend with the vette.

Posted by: ThePaintedMan Aug 22 2014, 01:27 PM

Yeah, that's what I think Shane. I think the speeds (or lack thereof) and both lateral/horizontal G's we're going to hit with the car are far less than what's necessary to spin the tire on the rim.

I'll bring them all with me and we can balance them as a "why not?" Can't hurt.

I also considered that most of those Cup guys were balancing the rim. After a few stints it's probably built up enough rubber to throw that off anyway, but it's still probably a good idea.

Not sure how aggressive those DTCs are, but the graphs that Porterfield shows on the R4-1 pads I'm putting on the car sure look impressive. With just crappy street pads I was braking at the last cone into the hairpin before... I wonder where the braking point will be NOW.

Posted by: Racer Chris Aug 22 2014, 01:56 PM

I doubt your tires will rotate on the rim with less than 200 hp, fairly small brakes, and a narrow body car.
Balance them.
One of the worst feelings is on an outlap with a badly out of balance race tire from rubber picked up on the previous cooldown lap.
It can shake so bad you'd think the car was about to fall apart.

Posted by: ThePaintedMan Aug 22 2014, 02:51 PM

Exactly the person I hoped would chime in Thanks Chris!

Though these are 180 TW tires, I don't think they're quite sticky enough to pick up rubber. Now what ends up on the inside of the rim is a different story. Sebring has marbles EVERYWHERE.

Posted by: carr914 Aug 22 2014, 03:28 PM

you could go with the Plastic BB balancing method

Posted by: Mblizzard Aug 22 2014, 03:30 PM

http://www.innovativebalancing.com/index.php? Just ordered some may have a track application if not against the rules. Won't matter if the tire moves.

Posted by: wndsrfr Aug 22 2014, 07:08 PM

You're going to LOVE those R4-1's......best stopping power I've had....

Posted by: campbellcj Aug 22 2014, 07:10 PM

I have always had mine balanced (wheels+tires). The owner of my tire shop is a racer so they take extra care with racers' jobs.

Posted by: mepstein Aug 22 2014, 08:45 PM

Worked well for me. Cheap, easy and leaves the rim clean. I will use it on future wheels.

Posted by: Matt Romanowski Aug 24 2014, 12:52 PM

Balance the tires and rims. Hoosier makes their beads bands a little looser than other companies so they tend to slip more than others, but I don't think you'll have much trouble.

If you have tires that always slip on the rims, then balance just the rim and don't worry about the tire being balance.

Posted by: brant Aug 24 2014, 06:37 PM

adding plastic bb's to the inside of a track car seems like adding extra weight that does not make you faster...

Posted by: mepstein Aug 24 2014, 07:23 PM

for me it was 3oz per wheel. But now I don't have to pay someone to balance the wheels and no lead weights stuck on the rim. I think you can use less weight to balance since the weight is further from center so the balance effect is greater.

Smooth is fast

Posted by: naro914 Aug 28 2014, 10:38 AM

I always balance wheels with tires on them and it makes a HUGE difference IMO. I've thrown a weight (forgot to tape it) and noticed immediately. Can't imagine not balancing them...

Posted by: stugray Aug 28 2014, 01:08 PM

You also have to consider that most of us have some flavor of stock wheels which are old, and usually not perfectly straight/round.

So balancing seems to be a must. Even my "checked for out of round & straight" wheels have some pretty serious weights on them from the balancer.

Besides, both of my sons work at tire shops, so I get it done for free.