Poll: FF SPEC TIRE

[problemchild]

What if someone took a well dialed in car on those radials and then did a lap times vs tire camber 'sweep'. Or lateral G's vs camber with lots of averaging. maybe sweep from 3.5 to 2 degrees and back to take some of the other variables out. In 0.5 degree steps. Maybe a test day with a set of new hoosiers and some crowd finding Apexspeed style. My fear is that the difference is small and we are alienating Swift owners for no good reason. What if it is only 0.2 seconds delta per minute which might be less than the delta between a swift and a mygale or spectrum anyway. not sure if I am making sense, but just how sensitive are the cars to the change from say 2 degrees to 3.5??

Steve

Steve, I am not disagreeing with you, but I will point out that modifying 4 lower A-arms and adding a pair of tripod spacers, will probably be cheaper than a test day to see if it is worth doing. A good fabricator could probably build a "camber kit" to sell for less than a set of tires.
Adding a 1/2" worth of camber adjustment per corner does not need to involve moving pickup points or modifying chassis points. Assuming the tires turn out to be as fast or faster, the modifications would be paid for in tire cost savings in 3 weekends.

[Raceworks]

What if someone took a well dialed in car on those radials and then did a lap times vs tire camber 'sweep'. Or lateral G's vs camber with lots of averaging. maybe sweep from 3.5 to 2 degrees and back to take some of the other variables out. In 0.5 degree steps. Maybe a test day with a set of new hoosiers and some crowd finding Apexspeed style. My fear is that the difference is small and we are alienating Swift owners for no good reason. What if it is only 0.2 seconds delta per minute which might be less than the delta between a swift and a mygale or spectrum anyway. not sure if I am making sense, but just how sensitive are the cars to the change from say 2 degrees to 3.5??

Steve

That's generally how I like to do developmental tests. As I've said before, I'm willing to pitch in on a track rental (probably either TGPR or Roebling, as they're actually somewhat affordable) to do some group testing.

Hoosier since rolled back the recommended camber settings (see the file I linked to). It's now 3.0 front (+ or - 0.5) & 2.0 rear (again + or - 0.5). Based on what little time we got this weekend I'm thinking that on some chassis they may "like" less camber. Keep in mind the initial numbers were derived on a test with a single chassis type (Mygale).

Like Steve & Greg said, it looks like camber & tire pressures are the main differences in setup. On the dry Friday session I had softened the shocks & swaybars anticipating the car being a lot twitchier on the radials and that wasn't the case. For Saturday I went back to the same baseline we've run at Road Atlanta except for camber & tire pressures & the car worked much better. The biggest adjustment I had to make was that without the cantilver the rears are more stable, so I kept losing time anticipating that squirmy feeling the bias ply rears have.

[Max Power]

Did anyone catch the article about this in the June 2015 Sports Car? Excerpt from page 68:

The Formula Advisory Committee did extensive research and, after whittling it down to three possibilities, made a tire recommendation to the Club Racing Board. At the time of this writing, the SCCA National Staff is working with the tire manufacturer to get the best possible deal for an FF spec tire for the 2016 season and beyond. Although contract negotiations for this type of deal usually include a license fee to be paid to the SCCA, the primary focus for FF is on the best deal for the individual racer.

Any insight or speculation? I'm surprised it hasn't been discussed yet. Maybe we're all too busy searching couch cushions for pennies to fund our next set of tires, or is that just me?

[andyllc]

Did anyone catch the article about this in the June 2015 Sports Car? Excerpt from page 68:

The Formula Advisory Committee did extensive research and, after whittling it down to three possibilities, made a tire recommendation to the Club Racing Board. At the time of this writing, the SCCA National Staff is working with the tire manufacturer to get the best possible deal for an FF spec tire for the 2016 season and beyond. Although contract negotiations for this type of deal usually include a license fee to be paid to the SCCA, the primary focus for FF is on the best deal for the individual racer.

Any insight or speculation? I'm surprised it hasn't been discussed yet. Maybe we're all too busy searching couch cushions for pennies to fund our next set of tires, or is that just me?

Speculation....sure....Hoosier pro series tire rebranded without the word pro stamped on it (meaning not legal for pro series) and at a reduced cost.

[BWC54]

There is a new Hoosier tire in the 2015 catalog on page 17. It's a radial the same size as the Pro tire listed as an FF application. It has an ii tread pattern with an R60A compound. Anyone know anything about it? Catalog numbers are 43322 and 43327.

Is this the same as the Pro tire but made available to anyone through the normal Hoosier dealers? Pro tire is 43321 and 43326.

[andyllc]

There is a new Hoosier tire in the 2015 catalog on page 17. It's a radial the same size as the Pro tire listed as an FF application. It has an ii tread pattern with an R60A compound. Anyone know anything about it? Catalog numbers are 43322 and 43327.

Is this the same as the Pro tire but made available to anyone through the normal Hoosier dealers? Pro tire is 43321 and 43326.

Yep
See my post above...ran them at Mid Ohio Major

[BWC54]

Yep
See my post above...ran them at Mid Ohio Major

I didn't know the Pro tire was an R60A compound. I thought it would be between the R45 and R60. Maybe that's what they had to do to get it to last through a 3 race weekend.

[andyllc]

I didn't know the Pro tire was an R60A compound. I thought it would be between the R45 and R60. Maybe that's what they had to do to get it to last through a 3 race weekend.

We were surprised as well but we checked with Hoosier and they said that it was the same exact tire, compound and all. We had first thought the pro tire this year was a 45 but that apparently isn't the case.

[Rick Kean]

It's on the F1600 race series site: http://f1600series.com/competitors/9...tire-data.html

Thanks for the link Sam.

Without my Hoosier Decoder Ring, (I haven't called them), the yellow highlighted spreadsheet data under heading 'Vertical Deflection Data' appears more likely to be 'Static Spring Rate, lb/in'.

Can anyone confirm my WAG?

[DaveW]

Yup - that's what it is, IMO.

[SEComposites]

This topic has gone a bit quiet. Any news from anyone?

[TimH]

Well, Jim Edmonds from the AZ EFF group is leading the Masters Class championship up in the Canadian FormulaTour1600 series even though he missed the first two races. Consistent podium finishes will do that for you. Whatever else you might say the Toyos are plenty of fun. And when it rained we didn't bother to change anything but brake bias (most of our rear swaybars are already unhooked) and tire pressures.

[Hardingfv32]

This topic has gone a bit quiet. Any news from anyone?

In my effort to get something for FV I have learned that the FF RFP is out and getting a limited response.

Does the FF community have any knowledge of the RFP criteria?

Did the CRB communicate with FF participants about the direction the selection process was going?

Brian

[Todd Butler]

In my effort to get something for FV I have learned that the FF RFP is out and getting a limited response.

Does the FF community have any knowledge of the RFP criteria?

Did the CRB communicate with FF participants about the direction the selection process was going?

Brian

Look for Sept Fastrack (final) out 8/20. It was not in the prelim BTW.
You will have a chance to comment via the CRB letter system https://www.crbscca.com/ before BoD formally votes October 9-10 on the proposed rule for 2016.

Todd Butler
Area 13 Director.

[reidhazelton]

Read the next Fasttrack. If you agree with the proposal within, write a letter saying so. If you do not agree, write a letter saying so an state and alternative you feel is best.

If you choose to do nothing, do not complain about the decision.

Write. Your. Letter.

RH

[reidhazelton]

Poll...again.

This is close to a conclusion. See new thread here:

http://www.apexspeed.com/forums/showthread.php?t=69914