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Topic: 410s going to 16" d20 ASCS Hoosier tIre?
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Page 5 of 7 of 124 replies
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October 14, 2012 at
09:36:05 PM
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This message was edited on
October 14, 2012 at
09:46:26 PM by buzz rightrear
Reply to:
Posted By: CRobinson on October 14 2012 at 09:05:23 PM
Say you are running the cushion and the outside of the tire does hit something. Yes it will raise up the rr arm more than if the inside of the tire hits a bump because it will have more leverage. That has nothing to do with whether the tire is spaced out with a spacer or a diferent wheel though. The outside "load" will twist the rr torsion bar exactly the same whether you have the wheel spaced out with spacer or a different offset wheel. It only matters how far the tire is out. The wheel, wheel center, axle and spacers are all solid. The tire is what is floppy.
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no offense but,either you get it or you don't.
i never mentioned loading the suspension.
i mentioned loading the TIRE. that means the point on the tire that the load it is carrying is applied within the foot print of the tire. not the weight it is carrying.
like i said, you either get it or you don't.
this was posted earlier on this thread from an article authored by Wade Huisman, owner of Keizer racing wheels.
Assuming wheel width and position stay the same, the deeper offset or inner half, the tighter the chassis will act. This is done by moving the load point to the outside of the RR wheel. Likewise, the smaller the offset or inner wheel half, the looser the chassis will be. This is done by moving the load point to the inside of the RR wheel and not allowing for side bite. Here again, a deep inner half will create tire wear on the outside of the tire. A shallow inner half will create tire wear on the inside of the tire.
to indy and beyond!!
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October 14, 2012 at
09:40:11 PM
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Reply to:
Posted By: Twenty8 on October 14 2012 at 05:17:40 PM
There is no stat for how long a wheel will last . Most high budget teams buy new wheels every year. There are some teams that have ten year old wheels. It really depends on the abuse you give them.
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I'm having a hard time believing wheel flex and 10 yr old wheels go together.
If the wheels are flexing enough to make a bit of difference as to whether a spacer or an offset wheel makes a difference they would be coming apart long before 10 yrs of even moderate use.
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October 14, 2012 at
10:53:36 PM
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Reply to:
Posted By: MoOpenwheel on October 10 2012 at 04:20:10 PM
Jeff has always been known for saying exactly what he thinks. He's not wrong either. I'd love to see smaller and harder tires. I'd like for a tire to be competitive more than 1 or 2 nights too. That would save the local racers a ton of money. I'd also like to take our chances with setup and driving rather than hammer down motor deals. Maybe it'd mean less rubber down tracks too. Stock cars do it, why can't sprints?
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Rick Lafferty won 2 races this year at Williams Grove on used tires.
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October 15, 2012 at
03:02:44 PM
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Reply to:
Posted By: CRobinson on October 14 2012 at 06:34:48 PM
Better yet, I can scale my car with no tires on it, just wheels. And put the scale under just the rr beadlock. And the only thing that will change the weight is if I move the rr beadlock away from the car.
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An over exaggerated example ... but change the top and front wing angle on your scales, and let me know how that affects weight distribution. It doesn't ... because the car is static. At the track, how often is the car static? Only before and after the race. This was the fundamental flaw in Cubic's reasoning that he failed to acknolwdge.
Scales are a static tool used to baseline a setup, and that is about where their usefulness ends.
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October 15, 2012 at
03:04:30 PM
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Reply to:
Posted By: kooks on October 14 2012 at 09:40:11 PM
I'm having a hard time believing wheel flex and 10 yr old wheels go together.
If the wheels are flexing enough to make a bit of difference as to whether a spacer or an offset wheel makes a difference they would be coming apart long before 10 yrs of even moderate use.
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Chassis flex too. You have a tough time believing that since there are old chassis out there racing?
Everything on a race car flexes. It's phyically impossible not to. They just don't flex past their breaking point.
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October 15, 2012 at
05:54:39 PM
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A right rear tire squishes several inches under load. How much are you thinking a 1" more offset wheel flexes than a standard wheel?
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October 15, 2012 at
09:12:58 PM
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This message was edited on
October 15, 2012 at
09:15:07 PM by kooks
Reply to:
Posted By: fasterin3 on October 15 2012 at 03:04:30 PM
Chassis flex too. You have a tough time believing that since there are old chassis out there racing?
Everything on a race car flexes. It's phyically impossible not to. They just don't flex past their breaking point.
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No I don't have a hard time believing the Chassis flex or how old some cars are.
The number of times a chassis flexes/race is going to be a hundredth or less of what a rotating wheel supposedly flexes in addition to being far different in construction as to allowing it to flex without tearing apart.
As said many times you're dealing with a rubber (very flexible) tire on a wheel that even if it flexes isn't going to do squat compared to the flex of the tire.
Maybe if they want to save teams even more money they should ban offset wheels entirely.
One width of tire for the left rear and 1 width of tire for the right rear + no offset wheels = teams only need 4 wheels to have everything the competition does.
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October 15, 2012 at
11:03:02 PM
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Reply to:
Posted By: buzz rightrear on October 14 2012 at 08:37:46 PM
do you know the difference between weight and LOAD?
do you know what a pick-up-point is?
do you understand if you push down on the inside of the tire you are applying load at that point and if you push down on the outside of the tire you are applying load at that point?
it is not the weight that is on the tire that i am talking about. it is where the point of load is applied. if you take your hand and push down on the inner bead of the wheel you are loading the inner part of the tire. if you push down on the outer bead you are loading the outer part of the tire. it has nothing to do with what the weight on the tire would be on the scale.
you say you can put the outer bead lock rim on the scale and you can change the weight on it by moving it in and out. well you can leave the rim in the same place on the axle and move the scale to under the inner bead and the scale will read more weight. yet you haven't changed anything, except where you put the scale.
think of this. if you just took the wheel and placed it on two scales. one scale under the inner rim and one under the outer rim. then you applied downward pressure or were able to put a weight right where the wheel hub is where the two wheel halves meet. you would get a total weight reading from the two scales, but one scale would read more than the other. that is because the weight isn't being supported in the exact center, or middle of the wheel. the weight is being supported within the wheel at the point where the hub is located. now if you could take a wheel with a different off set and do the same thing, you would find that as you move the location of the hub within the wheel, you will change the amount of weight on each scale, even though you are applying the same total weight. as you move the wheel hub deeper into the wheel the more weight will be supported by the outer rim. that is because the point the load has been applied has been moved towards the outer part of the wheel.
you might even be able to place the wheel on the axle without a tire on it and put one scale under the inside rim and one scale under the outer rim and then note the weight on each scale as well as the total weight of both scales. then do the same thing with a different off set wheel and have the weight on each scale change while the overall weight on both scales stays the same.
there is also another simple test to show that where you apply load changes things. take two scales, place them a couple of feet apart. put a 2x4 across them. now put one of your feet on the 2x4 right in the middle between the scales and stand on it. you will show a total weight and a weight on each scale. now move to the left or to the right and do the same thing. you will have different weights on each scale, but the same total weight. that is because you are moving the load point.
the thing is, you have to understand that the placement of the wheel hub within the wheel makes a difference as to the loading of the inner or outer part of the tire.
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This post makes the most sense as far as explaining how different offset work... Nothing to do with wheels flexing just talking about the way it loads the tires.... I bet some of these guys think if you take a tie down shock and flip it upside down it will be a riser
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October 15, 2012 at
11:47:22 PM
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What we are trying to limit with a narrow right rear is the amount of usable horsepower right? Same with injection restrictors and wing size, dish depth, etc. Why don't we police what we are trying to limit? Hot Rod shows all over have a dyno for dyno competitions on a truck that pulls up to your car show. Get one to go to different tracks. Do a dyno pull. Pick a number for your max and tech is done. How much would engine prices drop if we went to a 700 hp max? Quite a bit. And, I bet you wouldn't be able to tell from the bleachers. Engine builders still sell engines, only now, instead of R&D hours spent on 1/16 of a horse, the R&D goes into the motor lasting the longest. Their investment goes down, so does the price of the motor. Come it with a motor at 800 hp and it's easy to detune down to 700. All engines can run. Uses all the current stuff up without having to do too much. This might not be for the WoO, but for a weekly track or sportsman class, why try to regulate horse power through the tires and wings? Just regulate the hp.
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October 15, 2012 at
11:48:05 PM
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p.s. I do agree with a narrow rr as well.
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October 16, 2012 at
07:15:41 AM
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Because it would take longer to dyno 35 sprint cars than race 35 cars. Because if you do it before the race everyone will tune UP after and because only teching the winner is fucking bullshit but usually how its done
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October 16, 2012 at
10:45:27 AM
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Reply to:
Posted By: comeon38 on October 15 2012 at 11:03:02 PM
This post makes the most sense as far as explaining how different offset work... Nothing to do with wheels flexing just talking about the way it loads the tires.... I bet some of these guys think if you take a tie down shock and flip it upside down it will be a riser
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Except for the wheels and axle are all one solid piece. Unless something is bending, the only way the outside or the inside of a wheel can press harder into the outside or inside of the tire, is if the whole rear end and both wheels roll together.
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October 16, 2012 at
12:58:42 PM
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Reply to:
Posted By: ebecker on October 15 2012 at 11:47:22 PM
What we are trying to limit with a narrow right rear is the amount of usable horsepower right? Same with injection restrictors and wing size, dish depth, etc. Why don't we police what we are trying to limit? Hot Rod shows all over have a dyno for dyno competitions on a truck that pulls up to your car show. Get one to go to different tracks. Do a dyno pull. Pick a number for your max and tech is done. How much would engine prices drop if we went to a 700 hp max? Quite a bit. And, I bet you wouldn't be able to tell from the bleachers. Engine builders still sell engines, only now, instead of R&D hours spent on 1/16 of a horse, the R&D goes into the motor lasting the longest. Their investment goes down, so does the price of the motor. Come it with a motor at 800 hp and it's easy to detune down to 700. All engines can run. Uses all the current stuff up without having to do too much. This might not be for the WoO, but for a weekly track or sportsman class, why try to regulate horse power through the tires and wings? Just regulate the hp.
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Isn't that why we have 360's? The object isn't just to slow them down but to unlock them a little to make the racing more exciting. To do that you need to have more HP available than most are able to put to the track. That makes the driver and setup a bigger part of the equation and also evens the field out a little. With todays technology in tire development, shocks, torsion bars, etc. the cars got so locked down that it got to the point where nearly anyone can put the hammer down and steer and look like a pro.That's why they needed to take a few steps backwards with the tires and the wings. We want these guys on the edge and pushing their limits when they enter a turn not just stomping and steering. That's what makes sprint car racing exciting.
There was an affordable, durable engine developed by Shaver and Schatz which used off the shelf Chevy parts that put out 700 HP and cost less than 20G. For some reason nobody wanted anything to do with it. Yet we still complain about sprint car engines costs whether it's 410, 360 or 358.
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October 16, 2012 at
02:48:23 PM
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This message was edited on
October 16, 2012 at
03:01:02 PM by buzz rightrear
Reply to:
Posted By: CRobinson on October 16 2012 at 10:45:27 AM
Except for the wheels and axle are all one solid piece. Unless something is bending, the only way the outside or the inside of a wheel can press harder into the outside or inside of the tire, is if the whole rear end and both wheels roll together.
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it's not that it pushes any harder as you move the hub within the wheel. it just pushes in a DIFFERENT PLACE within the wheel.
something IS bending. it is the tire. the tire is the part that flexes. the more you move the center hub towards the outside of the wheel, the more you are working the outside of the tire. it affects the lateral movement of the tire in relation to the wheel upon cornering. or in other words, it affects if, or how the tire will roll across or under the wheel. the tire doesn't stay in the same lateral position on the wheel. under cornering the wheel will move laterally within the tire. how much depends on air pressure, cornering forces, side wall construction, available traction, tire foot print off set from the chassis and wheel center offset. all things being equal, adjusting the center offset of the wheel hub will affect tire roll under. sometimes you may get very little roll under and sometimes you may get a lot. it just depends on the conditions.
as you move the center hub deeper into the wheel, the more it wants to try to roll the tire under the wheel.
yes you can also control tire roll under with air pressure, but sometimes you just don't want to drop the pressure.
take a look at the pic below and you can see how much a tire rolls and deforms. moving the hub center within the wheel can assist in determining the amount of roll under.
to indy and beyond!!
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October 16, 2012 at
03:02:26 PM
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Reply to:
Posted By: brettco on October 16 2012 at 07:15:41 AM
Because it would take longer to dyno 35 sprint cars than race 35 cars. Because if you do it before the race everyone will tune UP after and because only teching the winner is fucking bullshit but usually how its done
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ever try to start a sprint car without a starter on a chassis dyno?
to indy and beyond!!
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October 16, 2012 at
06:23:54 PM
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Reply to:
Posted By: buzz rightrear on October 16 2012 at 02:48:23 PM
it's not that it pushes any harder as you move the hub within the wheel. it just pushes in a DIFFERENT PLACE within the wheel.
something IS bending. it is the tire. the tire is the part that flexes. the more you move the center hub towards the outside of the wheel, the more you are working the outside of the tire. it affects the lateral movement of the tire in relation to the wheel upon cornering. or in other words, it affects if, or how the tire will roll across or under the wheel. the tire doesn't stay in the same lateral position on the wheel. under cornering the wheel will move laterally within the tire. how much depends on air pressure, cornering forces, side wall construction, available traction, tire foot print off set from the chassis and wheel center offset. all things being equal, adjusting the center offset of the wheel hub will affect tire roll under. sometimes you may get very little roll under and sometimes you may get a lot. it just depends on the conditions.
as you move the center hub deeper into the wheel, the more it wants to try to roll the tire under the wheel.
yes you can also control tire roll under with air pressure, but sometimes you just don't want to drop the pressure.
take a look at the pic below and you can see how much a tire rolls and deforms. moving the hub center within the wheel can assist in determining the amount of roll under.
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It seems to me what you are trying to say is if you had an 18" off wheel where the hub was all the way out where the beadlock is, that only the outer sidewall of the tire would be holding up the whole weight of the car. That is impossible without the wheel bending. It doesn't look like it is bending in your picture. Only 1" more offset isn't going to make it bend more anyway. If you push down on the axle or push on it sideways, both beads on the wheel are solid to the axle. Both beads are working no matter what type of wheel you are running. it is solid. A lot of people already said they went to longer axles so they don't need to own different offset wheels anymore. That is the only reason they used to need them. Now you can just use spacers most of the time.
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October 16, 2012 at
06:40:18 PM
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Reply to:
Posted By: cubicdollars on October 13 2012 at 05:26:08 AM
The only sickness is your perversion for communist made "spint" cars. Watch out, a wheel cover might lop your head off when it flies off because someone runs a little more wheel offset and the whole wheel rolls under the car like all you geniuses keep claiming. A wheel won't roll under when the track is wide open, and it certainly doesn't roll under when it is dead slick when the clueless bolt on 7 off wheels for any other reason than they don't have any spacers left to take out.
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Hey Cubic,
Its better to remain silent & be thought a fool,than to open your mouth & remove all doubt! hahaha
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October 16, 2012 at
07:14:07 PM
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This message was edited on
October 16, 2012 at
07:15:32 PM by buzz rightrear
Reply to:
Posted By: CRobinson on October 16 2012 at 06:23:54 PM
It seems to me what you are trying to say is if you had an 18" off wheel where the hub was all the way out where the beadlock is, that only the outer sidewall of the tire would be holding up the whole weight of the car. That is impossible without the wheel bending. It doesn't look like it is bending in your picture. Only 1" more offset isn't going to make it bend more anyway. If you push down on the axle or push on it sideways, both beads on the wheel are solid to the axle. Both beads are working no matter what type of wheel you are running. it is solid. A lot of people already said they went to longer axles so they don't need to own different offset wheels anymore. That is the only reason they used to need them. Now you can just use spacers most of the time.
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like i said before, either it makes sense or it doesn't to you. there are a lot of things that don't quite make sense to me involving sprint cars.
there are way too many teams that can afford to have anything they want and most of them have different offset wheels. and they use them. when discussing set up options with different teams, especially when it comes to wheel spacing, we always make sure we know what wheel offsets we are talking about because it does make a difference. if wheel offsets made no difference, that info would not be of any concern.
not only does the wheel center offset affect the way the tire is loaded (and load is different from weight) it affects the effective spring rate at that corner of the car.
and if you moved the wheel center all the way out to where the bead lock is on the large floppy sidewall tires we run, you just might trip the tire over itself and dig the rim into the ground.
have you ever run an 8" offset on an 18" RR wheel? i have and it darn near tears the outer sidewall off the tire because it wants roll the outer part of the tire so hard.
to indy and beyond!!
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October 16, 2012 at
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Reply to:
Posted By: dollansky_7_fan on October 10 2012 at 04:47:38 PM
One problem to being able to run a tire more than one night, is the cost of the tire will go up. They have to recoup cost from lost sales. In the end it won't save anyone money
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You can not run an ASCS medium more then one night at knoxville, If you think so I have about twenty of them that look like new I would love to sell you!! The 305 guys won't even take them for free.
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October 16, 2012 at
09:51:35 PM
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Reply to:
Posted By: kooks on October 14 2012 at 09:40:11 PM
I'm having a hard time believing wheel flex and 10 yr old wheels go together.
If the wheels are flexing enough to make a bit of difference as to whether a spacer or an offset wheel makes a difference they would be coming apart long before 10 yrs of even moderate use.
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alum. rims are alot thinner today than they were 10 years ago. We have found new rims to be bent that we never felt it got dinged that hard.
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