May be a dumb Question about a 2 tire stop

Clutch

Clutch

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But.... if it were possible, I mean if they made a jack suitable would anyone find benefit from changing 2 Front tires ...or 2 rear tires instead of always right sides?
I say this because I saw a lot more front clearance on the Xfinity cars today and thought a jack could be designed to go under the middle.
Maybe on super speedways....or short tracks..? any thoughts. I mean are there tracks where the front or rear wear more than the other?

edit.. I've asked plenty of dumb Q's before. Lol
 
Clutch said:
But.... if it were possible, I mean if they made a jack suitable would anyone find benefit from changing 2 Front tires ...or 2 rear tires instead of always right sides?
I say this because I saw a lot more front clearance on the Xfinity cars today and thought a jack could be designed to go under the middle.
Maybe on super speedways....or short tracks..? any thoughts. I mean are there tracks where the front or rear wear more than the other?

edit.. I've asked plenty of dumb Q's before. Lol
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Possibile but less desirable and tougher to do logistically, due to the awkward positions. You also have to deal with the cars pitting on front and behind, puts the jackman and others at more risk.
 
I've seen it done on dirt cars a few times ... rears.

Not sure what there would be to gain on a Cup car.
 
Clutch said:
But.... if it were possible, I mean if they made a jack suitable would anyone find benefit from changing 2 Front tires ...or 2 rear tires instead of always right sides?
I say this because I saw a lot more front clearance on the Xfinity cars today and thought a jack could be designed to go under the middle.
Maybe on super speedways....or short tracks..? any thoughts. I mean are there tracks where the front or rear wear more than the other?

edit.. I've asked plenty of dumb Q's before. Lol
Click to expand...

I think people tend to think of tire wear in two parts as well, the lefts and the rights. I think compounds or soft/hard get separated by left and right too.
 
Greg said:
I think people tend to think of tire wear in two parts as well, the lefts and the rights. I think compounds or soft/hard get separated by left and right too.
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Maybe they think in lefts and rights because that's all they know? :idunno: :D
 
Greg said:
I think people tend to think of tire wear in two parts as well, the lefts and the rights. I think compounds or soft/hard get separated by left and right too.
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aunty dive said:
I've seen it done on dirt cars a few times ... rears.

Not sure what there would be to gain on a Cup car.
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Any how I just want to thank you both for just not saying I am a moron for putting it out there. :)
 
Greg said:
I think people tend to think of tire wear in two parts as well, the lefts and the rights. I think compounds or soft/hard get separated by left and right too.
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Hard breaking on short tracks have to wear the fronts
 
I know that when I have only two tires put on my car I always tell the guy to put the new ones on front, and not either the left side or right side.

The again it usually takes them longer than 15 or 20 seconds to get the job done so maybe I'm missing something . . . :confused:
 
My bother went to a race at Jeffco Ga (aka Peach State) that Bob Senneker won in the 80s. I didn't get to go to that one, but we always updated the other one with a post report in those cases.
He said Senneker did a pit stop that consisted of only changing both rear tires during that 200 or 250 lap race. It must have worked.
 
Greg said:
My bother went to a race at Jeffco Ga (aka Peach State) that Bob Senneker won in the 80s. I didn't get to go to that one, but we always updated the other one with a post report in those cases.
He said Senneker did a pit stop that consisted of only changing both rear tires during that 200 or 250 lap race. It must have worked.
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This is why I love this site. Right or wrong, just ask and we find out lots of interesting stuff!
 
Clutch said:
Hard breaking on short tracks have to wear the fronts
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Most of the torture goes to the right front due to the weight tranfer and braking, more pressure and friction going on there. Thats why they build as much weight percentage to the left as legally possible. Thats why overdriving corner or turn entrance accelerates tire wear, and corner exit speed is preferred, at least imo.
 
In general terms terms, assuming reasonable balance, at most Cup tracks changing the rears only would result in a big push. Opposite for fronts only ... too loose.
 
Greg said:
Most of the torture goes to the right front due to the weight tranfer and braking, more pressure and friction going on there. Thats why they build as much weight percentage to the left as legally possible. Thats why overdriving corner or turn entrance accelerates tire wear, and corner exit speed is preferred, at least imo.
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You may actually be supporting my theory....So why not 2 new front tires?
 
At this level, nobody's far enough off to attain balance by doing that. These guys adjust with pressure changes of a pound or so. Sometimes 10ths of a pound.

Falloff affects all 4 tires ... rights more so because the loads are quite a bit higher.
 
Clutch said:
But couldn't this be figured out mathematically? I'm sure you are right but I like the discussion. :D
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Races have been won with off the wall setups and in-race changes.

Creative people willing to gamble are people you want in your team.
 
Clutch said:
You may actually be supporting my theory....So why not 2 new front tires?
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All things being equal both right tires wear faster. The right front just gets the most torture. In some cases you can actually see the nose dip or squat entering the corners.
Then think of the weight as liquid, and how that would transfer when turning right and braking.
On corner exits the right rear is gettng more transfer, friction, heat.
The RR the 2nd most critical point imo.
I also think of two cars racing, one enters the corners more aggressively, the other one concentrates more on good corner exits. The one overdriving the entrance will use up his tires faster, and have a harder time passing the fast one off the corners.

Note the water or liquid idea is just a general idea, not a completely perfect analogy. Longer tracks and increased banking neutralizes some of the above points
 
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Greg said:
All things being equal both right tires wear faster. The right front just gets the most torture. In some cases you can actually see the nose dip or squat entering the corners.
Then think of the weight as liquid, and how that would transfer when turning right and braking.
On corner exits the right rear is gettng more transfer, friction, heat.
The RR the 2nd most critical point imo.
I also think of two cars racing, one enters the corners more aggressively, the other one concentrates more on good corner exits. The one overdriving the entrance will use up his tires faster, and have a harder time passing the fast one off the corners.

Note the water idea is just general idea, not a completely perfect analogy. Longer tracks and increased banking neutralizes some of the above points
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The water analogy is perfect. I just wonder if the right rear takes more abuse on a short track as the left front....but quite possibly it does.
 
Clutch said:
The water analogy is perfect. I just wonder if the right rear takes more abuse on a short track as the left front....but quite possibly it does.
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Not as confident on that one, but I believe the RR does take more abuse the LF. @aunty dive could answer that one better.
 
Yes, it does. On corner exit, weight transfers from the left front to the rr.

Cross-weight. Wedge.
 
As simple it sounds distance is also a good factor to consider. The rights take the longer away around, they have more distance to cover (well maybe not a big deal) .
I am not sure if stagger factors into the current tires, but you if so the taller tires are on the right. Weight or Gravity will transfer to the right when turning left.

It is ovals but building a car that wants to make left circles is another evidence that right tires get more torture.
 
Greg said:
As simple it sounds distance is also a good factor to consider. The rights take the longer away around, they have more distance to cover (well maybe not a big deal) .
I am not sure if stagger factors into the current tires, but you if so the taller tires are on the right. Weight or Gravity will transfer to the right when turning left.

It is ovals but building a cars that want to make left circles is another evidence that right tires get more torture.
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Absolutely. I guess I'm trying to figure out how much braking comes into play. It was just a thought. :D :idunno:
 
pjmolo said:
I know that when I have only two tires put on my car I always tell the guy to put the new ones on front, and not either the left side or right side.

The again it usually takes them longer than 15 or 20 seconds to get the job done so maybe I'm missing something . . . :confused:
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Last time I got just two tires for my car, the chain tire store would not put them on the front because the gummerment said that it is safer to put new tires on the rear of car, so instead of arguing with them, I brought my car home and switched them around.
 
Greg said:
As simple it sounds distance is also a good factor to consider. The rights take the longer away around, they have more distance to cover (well maybe not a big deal) .
I am not sure if stagger factors into the current tires, but you if so the taller tires are on the right. Weight or Gravity will transfer to the right when turning left.

It is ovals but building a car that wants to make left circles is another evidence that right tires get more torture.
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So what about Sonoma and Watkins Glen?
 
Clutch said:
So what about Sonoma and Watkins Glen?
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I dunno my first guess the lefts wear faster due to more right turns. But to a lesser extent because there is some criss crossing or back and forth on a RC.
 
Greg said:
I dunno my first guess the lefts wear faster due to more right turns. But to a lesser extent because there is some criss crossing or back and forth on a RC.
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aunty dive said:
No stagger and same construction and compounding on both sides. Almost every road course runs clock-wise. The turns are predominantly rights.
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Thanks for all of your input guys. Appreciated. I enjoyed it.
 
Greg said:
As simple it sounds distance is also a good factor to consider. The rights take the longer away around, they have more distance to cover (well maybe not a big deal) .
I am not sure if stagger factors into the current tires, but you if so the taller tires are on the right. Weight or Gravity will transfer to the right when turning left.

It is ovals but building a car that wants to make left circles is another evidence that right tires get more torture.
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Stagger is still there but much less than was used when bias ply tires were in use.

I started posting the TIRE CODES and specs in dpk's pre-race threads a few races ago. It's there for Homestead ... this week the stagger is 1.11 inches. In the moldy old days, 2.5 to 3 was the norm.

I ran my super modified at Phoenix with 6 inches on the rear. 8 or so on the little tracks. Those cars, like sprinters, ride on the rr unlike stock cars which lean on the rf.
 
Might put the boat in the water tomoro...see if this winds dies as expected. :)
 
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