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I thought it was Bob's AS-CSP-ESP-BSP-SM car.

Pat

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'92 Sentra SE-R, daily driver and track car
'82 Camaro Z28, ESP, 65% prepared, 50% ownership

Upset about Stock class proposals? Get PISST!

Steve Hoelscher:

You don't need wheel speed sensors to have traction control.  There are systems that will control angular acceleration of the crankshaft.  Catch that one. 

 

 
Yeah, that may be judged to be "Traction Control", but my *personal* opinion is that it really isn't.  The systems that look at how fast the car revs while in a given gear, and decides that if the rate is beyond a set value the tires must be spinning, is (in my feeble mind) just a dynamic rev limiter.  If it isn't actually looking at differing wheel speeds to determine actual longitudinal slip, then to me it's not really "Traction Control".  We probably need a REALLY good definition of TC if cars will be penalized (or excluded) for it.  The above system, in my understanding, is very traction dependent on what that "Maximum Acceleration Rate" value is - so if you do your testing on a given surface, and the characteristics of that surface change (like they do constantly), it really doesn't perform very well.  It may work OK as a launch control, provided the longitudinal grip levels are similar to the test environment (or you guessed really well), but corner exit is a crap shoot.

My personal opinion is that rev rate control should be legal everywhere that you can use an after market (or homebuilt) ECU, and Traction control penalties should be assessed in conjunction with ABS - in terms of if you have wheel speed sensors or not.  It's just too hard to police (and define) otherwise.
 

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Ed Locke
2006 CR-SCCA XP Champion (Hey! I showed up.)
#248 SM/XP/DP/GS/BS/etc.
At Track Graphics (http://www.attrackgraphics.com)
Skull Motorsports (http://www.skullmotorsports.com)

Ed Locke:

 

Yeah, that may be judged to be "Traction Control", but my *personal* opinion is that it really isn't.  The systems that look at how fast the car revs while in a given gear, and decides that if the rate is beyond a set value the tires must be spinning, is (in my feeble mind) just a dynamic rev limiter.  If it isn't actually looking at differing wheel speeds to determine actual longitudinal slip, then to me it's not really "Traction Control".

[huge smartass] 

 

See, the tires are connected to the engine with these neat things called gears.  They don't really bend or flex too much, so whatever the tires are doing, so is the engine. Hence, you're measuring the same damn thing.

 

[/huge smartass, back to regular smartass]

 

 

So yeah, anyway...  being that Tunnell took us all for a 2+ second victory, I don't really care WHAT his minimum weight is/was.  2 seconds isn't a 50 lb difference, it's not even a 500 lb difference.  Bob's car simply worked well, and Bob's a heckava driver.

That being said, and what I said to Bob before we got our trophies, if he sticks around in XP next year, we're going to try to make it harder for him to win.  I think the Spyder with some more development time is definitely going to be able to make it interesting. :)  We learned a ton the past week, and the car was already full of compromises and weak points we knew from before.
 

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Jesse
-2002-2006 E-stock 93 MR2 (sold)
-2007-2008 XP Spyder

129STS:

[huge smartass] 

 

See, the tires are connected to the engine with these neat things called gears.  They don't really bend or flex too much, so whatever the tires are doing, so is the engine. Hence, you're measuring the same damn thing.

 

[/huge smartass, back to regular smartass]

 

 

So yeah, anyway...  being that Tunnell took us all for a 2+ second victory, I don't really care WHAT his minimum weight is/was.  2 seconds isn't a 50 lb difference, it's not even a 500 lb difference.  Bob's car simply worked well, and Bob's a heckava driver.

That being said, and what I said to Bob before we got our trophies, if he sticks around in XP next year, we're going to try to make it harder for him to win.  I think the Spyder with some more development time is definitely going to be able to make it interesting. :)  We learned a ton the past week, and the car was already full of compromises and weak points we knew from before.
 

 

/Huge smartass on

 

So you are the compromise and Jim is the weak point???

 

/Huge smartass off

 

Have Jim send me that 25# bar and let me know how much shipping was  

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Tracy Ramsey
Team Blenderblaster
2000 MR2 DP Spyder

Zauskycop:

129STS:

[huge smartass] 

 

See, the tires are connected to the engine with these neat things called gears.  They don't really bend or flex too much, so whatever the tires are doing, so is the engine. Hence, you're measuring the same damn thing.

 

[/huge smartass, back to regular smartass]

 

 

So yeah, anyway...  being that Tunnell took us all for a 2+ second victory, I don't really care WHAT his minimum weight is/was.  2 seconds isn't a 50 lb difference, it's not even a 500 lb difference.  Bob's car simply worked well, and Bob's a heckava driver.

That being said, and what I said to Bob before we got our trophies, if he sticks around in XP next year, we're going to try to make it harder for him to win.  I think the Spyder with some more development time is definitely going to be able to make it interesting. :)  We learned a ton the past week, and the car was already full of compromises and weak points we knew from before.
 

 

/Huge smartass on

 

So you are the compromise and Jim is the weak point???

 

/Huge smartass off

 

Have Jim send me that 25# bar and let me know how much shipping was  

 

What's the plural of Illinois?   :)

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Jesse
-2002-2006 E-stock 93 MR2 (sold)
-2007-2008 XP Spyder

Bewbies!

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Tracy Ramsey
Team Blenderblaster
2000 MR2 DP Spyder

129STS:

[huge smartass] 

See, the tires are connected to the engine with these neat things called gears.  They don't really bend or flex too much, so whatever the tires are doing, so is the engine. Hence, you're measuring the same damn thing.

[/huge smartass, back to regular smartass]

Actually, no.  (I mean "the same damn thing" thing, not the gear thing, I'm with you on that!)

If you are comparing wheel (or crank) speed to a known reference of actual vehicle speed, like another (undriven) wheel, you have a pretty accurate indication of slip.  If you compare it to something like "time" and assume a maximum rate before slippage occurs, you have a MUCH worse indication of slip - because it is based on an assumed maximum rate of acceleration that is bound to be in error - you just don't know by how much.  Do you assume the maximum rate based on straight line acceleration on grooved clean pavement, or do you base it on corner (side loaded) acceleration on a pile of sand?

Now you could reference the crank acceleration rate to an accelerometer to determine if the vehicle was accelerating as quickly as the engine, but I'm guessing the resolution of the accelerometer isn't good enough to do that very accurately either. It gets even more complicated when you aren't going in a straight line, but we never do that, do we?

You need a wheel sensor for real traction control. 

BTW, you can't be a huge smartass and fit in a Spyder.  You need a pretty scrawny ass for that.  Believe me - I know.  (And not because I did fit in a Spyder!)

And you don't need a plural of Illinois - we can take care of everything with just one.  Does the plural of Florida end in -as or -uhs?

 

 

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Ed Locke
2006 CR-SCCA XP Champion (Hey! I showed up.)
#248 SM/XP/DP/GS/BS/etc.
At Track Graphics (http://www.attrackgraphics.com)
Skull Motorsports (http://www.skullmotorsports.com)

Whatever TC system you have, you can typically "dial it in" for those exact reasons you've stated.  Stan's RaceLogic setup on his Vette has multiple settings for % of slip, as well as a rain setting.  Even then, he was telling me that the Rage Logic still can't slow the engine down as quickly as it's accelerating once it gets going.  If you have a crank sensor type, you should be able to dial it in via software.  You still cannot just stomp the pedal mid corner and come out like a rocket...  you still gotta DRIVE the thing.

And we gutted the Spyder, so there's much more room for my smartass-ery.  We even took out the windshield to give ourselves more room. :)

And again, TC isn't going to win or lose the Championships until we (XP drivers) can actually run faster than SM2 (cough overweight XP cars).  The fastest XP scratch time was still about a half second slower than SM2 on the West course.  Hopefully by next year, we can kill most if not all of that.
 

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Jesse
-2002-2006 E-stock 93 MR2 (sold)
-2007-2008 XP Spyder

FYI - The Racelogic system was ruled at last year's Nationals to be legal in SP, because it is simply an engine management system according the our definitions.  There is no restriction on the data collected for calculations within the engine management system in any of the classes that allow open engine management.  The point where a system in XP crosses the line between engine management and traction control is when the system is capable of applying a braking force to limit wheelspin.  I have not yet seen an aftermarket traction control system with active braking capability, but the potential for significant improvements in steering response and cornering are very real - just take a drive in one of the new cars that has a decent system.

-Chris 

 

FWIW, our fastest runs usually come with the Racelogic TC dialed way back, or off.  If you just mat the throttle, the cuts hurt your acceleration more than it helps. 60' times at the Pro Solo were almost identical with TC and without.  As jesse said, you still have to DRIVE the car.  I thought very hard about unplugging the system and ditching some ballast on day 2. 

 

 

Bob's car was about 300lbs overweight.  I watched him drive and he is a surgeon.  That said, he had prototype R25B radials that were not availalble to anyone else.  Quite honestly that is irritating as hell.  Like Stan and Jesse, I put well over a thousand hours last year in developing the car.  I am running Hoosier stickers too, so why the "have's" and "have nots?"  Do we get the R25Bs developed for next year and Bob or someone else has some prototype "R25Cs?"   Our suspension was not dialed in on the first day, but better on the second.  Given how crappy the surface is combined with the tire situation, I am thinking seriously about not coming back to Heartless Park.    

fzust:

Bob's car was about 300lbs overweight.  I watched him drive and he is a surgeon.  That said, he had prototype R25B radials that were not availalble to anyone else.  Quite honestly that is irritating as hell.

Keisel had them on his EM car as well.  Why is it irritating?  I ran a scratch time to beat Bob by a tenth on my 3rd run on the West course.  Given how NOT-ideal our setup is, it doesn't irritate me at all.  Bob's been driving THAT car for years, and it was already a dialed in, FAST championship SM car.  Pulling out 200 lbs and putting slicks on it certainly didn't make it any slower.  We're still behind SM2 by over a half second, so I'm not worried at all.

 

Like Stan and Jesse, I put well over a thousand hours last year in developing the car.  I am running Hoosier stickers too, so why the "have's" and "have nots?"

Correction, Jim Bledsoe has thousands of hours in the car.  I have worked on it less than 40, and have only driven it ~8 times, and never 2 events in a row without big changes until the Finale and Nats, and then we still did some relatively big setup changes.

Again, being that Stan ran scratch times with Bob on the East course, and I ran scratch times with Bob on the West course, I don't think the tires made a large difference.  You do realize that SM2 was faster than XP, on DOT tires, and in cars with full interiors, right?  Bob's tires were not a deciding factor what-so-ever.
 

Do we get the R25Bs developed for next year and Bob or someone else has some prototype "R25Cs?"

This is prepared.  This should not have been a surprise to you or anyone else.  There are very few rules about tires in P and M classes.  You can make, mold, "treat", etc your tires anyway you want.  Honestly, I was surprised you guys showed up with slicks THAT wide on the Elise.  With the typical late September temps of Topeka in a car under 1800 lbs, I'd be looking at smaller, NARROWER tires that got up to temp.  Bledsoe did that from last year to this year, going from the 285/335 setup to the 245/285 setup.  Much better results.

Given how crappy the surface is combined with the tire situation, I am thinking seriously about not coming back to Heartless Park. 

Clearly, you never ran at Forbes Field if HPT is a "crappy surface".  Everyone runs on the same surface, on the same courses.  It still comes down to who has the best setup and puts together 2 great days of driving.  I hope you come back Fred.  The car's obviously got lots of potential, and is what XP is all about.  Let's make next year's Champion actually have to work for it! :)

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Jesse
-2002-2006 E-stock 93 MR2 (sold)
-2007-2008 XP Spyder

fzust:

Bob's car was about 300lbs overweight.  I watched him drive and he is a surgeon.  That said, he had prototype R25B radials that were not availalble to anyone else.  Quite honestly that is irritating as hell.  Like Stan and Jesse, I put well over a thousand hours last year in developing the car.  I am running Hoosier stickers too, so why the "have's" and "have nots?"  Do we get the R25Bs developed for next year and Bob or someone else has some prototype "R25Cs?"   Our suspension was not dialed in on the first day, but better on the second.  Given how crappy the surface is combined with the tire situation, I am thinking seriously about not coming back to Heartless Park.    

 

Everyone had the ability to run the faster Hoosier A6 tire.  I turned 44.9 first heat west course (Tue/Wed) in a 400lb overweight "XP" car. I think that R25B tire probably slowed him down.

BTW, we don't run traction control on our car, even though our ECU has an acceleration type system in it..  Beth forbids it, as only "real" men and women drive cars without traction control. :-)

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Erik Strelnieks
93 3-ROTOR RX7
01 Honda S2000
05 SLK 350 AMG
08 BMW 135i

fzust:

Bob's car was about 300lbs overweight.  I watched him drive and he is a surgeon.  That said, he had prototype R25B radials that were not availalble to anyone else.  Quite honestly that is irritating as hell.  Like Stan and Jesse, I put well over a thousand hours last year in developing the car.  I am running Hoosier stickers too, so why the "have's" and "have nots?"

 

I haven't investigated the tires on Bob's car but I doubt they were anything "unavailable to anyone else".  I have worked closely with Hoosier for more than 10 years, I know how they work and that isn't Hoosier's practice.  Did you call Hoosier and talk to them about what was available?  

 

 

fzust:

  Do we get the R25Bs developed for next year and Bob or someone else has some prototype "R25Cs?"   Our suspension was not dialed in on the first day, but better on the second.  Given how crappy the surface is combined with the tire situation, I am thinking seriously about not coming back to Heartless Park.    

 

I don't understand your issues with the surface.  What's so crappy about the surface?  It has less crap offline that Forbes.  It has adequate grip levels.  My DP car has good grip at HPT.  I ran 7/10ths (scratch) off Bob's XP winning times on the east course (don't know about the west course where I never got a good run). 

You can't seem to deal with the HPT surface so instead of working on solving the problem you quit?  That's not how a Champion would approach the problem.  Then again maybe we just identified the problem?

 

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Steve Hoelscher
#27 DP - Toyota MR2
2006 DP National Champion
'98, '99, '00, '02 DSP National Champion
http://www.terriehoward.com

Steve Hoelscher:

I haven't investigated the tires on Bob's car but I doubt they were anything "unavailable to anyone else".  I have worked closely with Hoosier for more than 10 years, I know how they work and that isn't Hoosier's practice.  Did you call Hoosier and talk to them about what was available? 

I don't understand your issues with the surface.  What's so crappy about the surface?  It has less crap offline that Forbes.  It has adequate grip levels.  My DP car has good grip at HPT.  I ran 7/10ths (scratch) off Bob's XP winning times on the east course (don't know about the west course where I never got a good run). 

I've only heard of 3 guys who have been able to get sets.  Kiesel had them on the rear of the EM car, Fordahl apparently has been testing on them, and Tunnell had at least 2 fresh sets.  Dave McIllvanie has already posted that he's been trying to get THOSE tires for a year from Hoosier.  Personally, I could care less... since the A6's are the faster tire IMO.  SM2 had fastest fendered times on the West course, faster than EM, XP, etc.  DM ran in the wet on that course, and SM2 ran in the wet on the East course, so we really can't compare those two classes.

And again, the best PAXing fendered car on slicks was Tunnell at 23rd.  Following that was Keith Brown, at 52nd.  That says to me that slicks aren't the way to go.


 

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Jesse
-2002-2006 E-stock 93 MR2 (sold)
-2007-2008 XP Spyder

129STS:

... since the A6's are the faster tire IMO....

IMHO - It's a bit early to make that call.  I tend to believe the new radial slicks will prove faster than A6's, once A) Hoosier makes more sizes available and B) drivers have more time for testing.

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Steve Garnjobst
#75 XP
'99 Mazda Mutant

Steve Hoelscher:

 

I haven't investigated the tires on Bob's car but I doubt they were anything "unavailable to anyone else".  I have worked closely with Hoosier for more than 10 years, I know how they work and that isn't Hoosier's practice.  Did you call Hoosier and talk to them about what was available?  

 

 

 

Yes. I talked to Jeff at Hoosier and he said "No, we are not going to make an R25 in 16" sizes". Bob, Ron V and Sam P all had 16"s in a 25, but they are not "nobodys".

 I disagree that the A6 is faster than the slick or vice versa. I believe a car could be set up to be equally fast on either, but the set ups would be radically different.

This thread to an interesting turn, but I would like to congratulate Bob on his superior driving, superior car and superior tires (but like I said before, I believe he would have won on just about any tire).

 

"Keisel had them on his EM car as well." 

Just to clarify, for the Nationals I had the R25B on the rear only (not by choice) this was the first time I had ever run the tire....   I ran R25A all around for the Pro and the practice, went to Hoosier on Monday and saw the R25B rears with my R25A fronts (I asked if they had any R25A rears and I was told no, they no longer make them).....  I do belive the R25B is faster at HPT, but in my case where I had an unmatched set I belive it hurt more than helped (the car pushed so bad, which leads me to belive the B works beter).....  

I still think that DOT tires are faster at HPT.  Last year Andy Mckee drove my old BP RX-7 (the Carbon Fiber one) at Guy's test n tune.  For the record I was on the (at the time) new exclusive R35B radials (only me, Ron V., and Guy had them last year)...  Anyway my car and Andys car had a lot in common...    The main difference was the tires he was on V710's and I was on the radial slicks, after Andy took 6 runs in my car (on the second test n tune day he was 1.4 seconds slower in my car than his own)...  I put him in the car because I was .8 slower in my car than he was in his car (on good surfaces I would normally beat him) I put him in to see if it was me or the surface...  He got out and said "how do you drive this thing with so little grip"???   Stan Whitney also tested slicks versus DOT tires, and he runs DOT tires...  

 If Hoosier made DOT tires I could run for the front (20x9x13) I would try them to (I could run the 275 15 in the rear)..... 

 Jeff Kiesel

Jeff, your car is on the front page of the Hoosier website. 

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2002 Mercedes C230k, retired, 2005 Nationals STU DFL

1969 Beach Solo Vee and 1985 Lynx B Solo Vee