USAC Racing Forum

General Chat => Point .25 => Topic started by: Offset on June 27, 2011, 09:08:59 PM



Title: A35 vs D10 or D30 at Eldora
Post by: Offset on June 27, 2011, 09:08:59 PM
May we please have some advice as to the advantages and or disadvantages of using an A35 with grooving and siping compared to using a D10 or D30 with or without grooving or siping?  My sprintcar friends suggest a grooved A35 and siping on a dry / slick track.  Is a grooved D tire better without siping under the same conditions?  D20 changed to D30.


Title: Re: A35 vs D10 or D20 at Eldora
Post by: USAC Developmental on June 28, 2011, 10:08:29 AM
please note a D20 is not permitted

only D10, D30 or A35's


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Justin Posey Motorsports on June 28, 2011, 06:42:43 PM
It really depends on the weather and how much rubber the track takes as to the amount of grooving and siping you will wanna do if do any at all. The class you are running also plays a HUGE role in the tire compund and also the grooving and or siping you will that you will want to run at the given time of the day or night. The way you run a sprint car tire on a dry slick track is different than the way you will want your quarter midget tire in the same situation. 


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Offset on June 28, 2011, 09:53:35 PM
Thanks.  My inexperience shows.  I don't have many options for advice. 


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Justin Posey Motorsports on June 29, 2011, 08:59:36 PM
If you have any questions I will be happy to help you all that I can.


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Offset on June 29, 2011, 09:51:07 PM
My son races Sr Animal.  Last year the track always seemed to be dry and slick.  We ran D10s left side, A35s right side and couldn't get any traction.  He was very loose at the middle of the corner.  The car started at 50% cross and 3.25" of rear stagger.  Tightening via shock / spring adjustments didn't help.  Washed the tires with soap and water after each practice / heat.  The tires didn't appear to wear at all.  Is it worth grooving or siping?  Maybe we should start with the with grooved tires, then run slicks when the track dries?  Is straight cross block siping / grooving better under certain conditions than angled cross block?  Thank you.


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Justin Posey Motorsports on June 29, 2011, 10:24:39 PM
That is alot to get into and way to much for me to type. LOL If you wanna give me a call I will help you in anyway that I can.


Title: Re: A35 vs D10 or D30 at Eldora
Post by: streihawk8 on June 30, 2011, 01:04:04 AM
better have not used soap...that is not legal....water only


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Offset on June 30, 2011, 09:28:11 AM
I won't use soap this time.  My cheating didn't help.  The person I asked for help actually gave me a bad gear ratio and wrong wheel base / squaring info too.  The joke was on me.  Thank you


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Justin Posey Motorsports on July 01, 2011, 09:55:10 PM
The amount of soap that is in the water if you used say a 5 gallon bucket of water isn't enough to effect anything on the tire.


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Offset on July 02, 2011, 12:43:40 PM
The amount used produced only a few bubbles and we used the same garbage can of water all weekend.  David Gravel and the Hart brothers (sorry I missed their first names) spent some time with us last night at K-C.  They gave us a trove of both quarter midget and midget information.  I took notes and think they got us straightened out.  They are very nice people, as are most racers.  Thank you for your input.


Title: Re: A35 vs D10 or D30 at Eldora
Post by: streihawk8 on July 02, 2011, 08:39:31 PM
Justin and Offset I agree that there isn't enough to matter but the rule says NONE!


Title: Re: A35 vs D10 or D30 at Eldora
Post by: Offset on July 02, 2011, 11:34:38 PM
You've most likely saved us from disqualification.  I've memorized Appendix I section 714E and 737.  We'll be using clear potable water and legal tire compounds.  Thank you.  Hope to see you at Little E.  Rich Gerber


Title: Re: A35 vs D10 or D30 at Eldora
Post by: WingNut on July 04, 2011, 02:09:54 PM
Last year we had to run the A35 right sides and no grooving was allowed.  The track was no good for those tires and the racing (wrecking) proved that on Saturday.  Thankfully USAC decided to work the track frequently on Sunday and it was at least bearable.  If the track is like last year, I think you'll find the D10 good for early in the show and you might get to the D30s in the heavier classes. It's likely you'll want D10s on the left side all day. If grooving is allowed you'll need to do it. The dirt there is not very abrasive, but it also doesn't pack well (lots of dust). Last year I felt like a set of grooved D20s would have been very fast, but that wasn't allowed.