Swapping slicks around

I've got several events on my Hoosier bias tires now and starting to think about the sidewalls. How many of you guys swap your slicks & run them the other direction? Seems to me it would shorten the sidewall life.

Two theories here. At this point many will say don't bother now, and I would likely be one of them. If they have 30+ passes on them and you rotate them now they likely they will not be happy for a number passes if at all. The other camp will say rotate them on a regular basis, like every race or two at most. We do rotate ours every 15 passes or so on the dragster and did on the Cuda as well. On the heads up car we do it every three passes. We seem to get a lot of tire life on that car for what it is for sure. I know a lot of people who never rotate their tires as well. I am not sure there is any scientific data to support any of it being better or not, for years many slicks were one directional, so they could not be rotated. I also think it depends on the car, power level and rear suspension type, Ladder bar cars are inherently hard on tires, they have a lot of bite and most are not controlled well. That will kill the sidewall long before the tread is gone.

I've never had a set of slicks that wore evenly when left alone. So now I swap them after every weekend of racing. Extended life of the pair.

Some slicks/compounds can also start to "feather" across the tread. When this happens, it can reduce traction a bit. Reversing them can "clean" this feathering off for a while.

Your car looks to be hard on sidewalls, swapping slicks from side-to-side or not. If sidewall distortion is excessive enough, the distortion can extend into the tread area too. I run a rim at least as wide as the slick so I can run additional air pressure while still maintaining a wide contact patch......and reduce sidewall flex. I have 9" Hoosier radials on a 10" rims, running 21 lbs of air. But each car/suspension/weight/tire combo is different.

I do it (and it's PITA) because I'm cheap...

I wouldn't do it your case. If you want to break something you bend it back and forth.

I don't swap slicks on either car
G/F Camaro (factory torque arm)
or my Coronet (multi-leaf)

She killed the sidewall's on her Hoosier QTP's with 1.51-1.54 sixty foot on a 10.90 car.
But she double classes weeky.
She's on the 3754x now

My Coronet gives the M/T Radial's a workout but thats more of the weight than the power.
3,950 and sixty foots in the 1.57-1.61
They been in use since 2015

Any Mickey radial i used worked the same until the cords were showing.
Think the radial's are directional tho
Her's has 10" rim and 10" tread
I have 7" rim and 9" tread

Prob different need for tire rotation on a 10.0 car i'd imagine

It looks like your car hits the tire pretty hard, No expert here , I don't rotate, It would seem to me it might give you longer tread life but the reversing of the sidewall thread direction would total out the side walls before they were worn out

If the tires are not directional I would rotate them, what does Hoosier recommend on those tires You might want to try more air pressure in them also, see if it helps the 60 ft. times

My friend runs a PST Dakota. They change the slicks side to side every run. It runs 7.40's. They get more rune out of a set then not swapping them.

I'm Jay....and I'm a slick swapper.

When you start going faster, it's probably a good thing to do. Not only for the tire, just to get under there and wipe things down and check things out. It's just good maintenance and will probably save money and heartache in the long run.

More air will put more tire on the ground, wont be the fast way for sure.

If you want my opinion, and you did not ask for it but here goes. I can see from that pic you need a WAY STIFFER shock on the back of that thing. It works well but it is killing the sidewall. Tubes can also help, I don't think Hoosier makes a stiff sidewall that size. Mickey does and IMO just about every ladder bar car out there can benefit from stiff sidewalls and or tubes. Or better yet a stiff sidewall tire and a beadlock wheel. But just my .02 on the picture...

Somehow I new that

Thanks Al I do run tubes and use to run 15 lbs footbraking it with no issues. With all the changes and transbrake I'm still playing catch-up
With my combo. Most air I've been able to run so far is 12 lbs.without chattering. That pic was 11 lbs and if I can zero in on shock adjustments I should be able bring the air pressure back up.

Well you don't necessarily need more air. You need the amount of air that track conditions dictate. The better the track the less air you can run, conversely the worse the track conditions the more air you need. When the track is poor you need as much contact patch as possible. MOre air will do just that, as the rear end housing is pushed down the tire will flatten out giving you more contact patch. Less air for a tight track will allow the tire to cup in the center and give you less tire on the ground, giving you more wheelspeed. It is chattering cause there is not enough power to overcome that with the full tread making contact. You need to tighten the extension and lower the air pressure to overcome that...

Correct.



Uhh...what? The better the track, the MORE air you can run. Your goal should be the most air pressure you can get away with. This keeps the sidewalls from killing themselves, and keeps the car happy at the other end. When the track is cool and tight, you should be able to run much more pressure than compared to a hot greasy day.

Exactly backwards...But what do I know. Hit the tire to hard it will shake or try to drive over itself as there is not the power available to drive through it. Letting air out allows the tire to cup at the hit and less tire Is in the track, basic physics. Fist move of the tire is DOWN. The more air you have in that tire the more of a contact patch you have on the ground during that first move. On a good track you will wad the tire up and if you have any power at all will shake the tire. TO solve that on a good track take out air and tighten the shocks. On a bad, hot, greasy track you want to run less shock and more air..

SHOCKS control the hit on the tire not air. We run 5lbs of air and you will hardle see a wrinkle on our car. On the small tire heads up car on a good track we will run as little as 9lbs on a 29.52x10.5 with a very stiff shock setting and one again you will hardly see a wrinkle in the tire. When the track get hot and greasy we will run 9.75-10lbs and loosen the shocks to get more rubber on the ground. This car is usually in the 1.12-1.15 60' range with a SB no power adder deal. My sons car goes 1.04 60' on a 13.5" slick


The idea of as much air as you can is old school slow thinking. Wheelspeed is what gets a car QUICKLY down a track. Tubes will help a sidewall as will a beadlock. Most importantly a GOOD shock will keep the sidewall alive. Cheap shocks with inadequate valving will kill a sidewall in a hurry. I understand the thought process you are using and used to think that way myself years ago. I have grown and learned over the years what works and what does not.

This is what happens with to much air and not enough shock. And this is not a bad one 5.5lbs and 2 from full stiff

https://www.youtube.com/watch?v=3Hslwkm9zps

This is the same track same day with 1/4lb less air and two clicks in the shcoks. The track was very tight this weekend and we just misread the track first pass. This was a 1.044 60' pass 5.25lbs full stiff. We need to get some stiffer shocks as we are out of valving now with this engine. Once we handle that there will be NO wrinkle and the 60's will dropout

https://www.youtube.com/watch?v=tF4QXmXRqU4

Using dragster video as it's easier to see the affects.

OP is running a 10.0 car that likely 60's in the 1.3Xs and weighs 3200lbs...not a dragster that runs 1.0Xs or a 10.5 headsup car. This is apples to oranges.

In my car, with a similar size tire as OPs, running anything excessively low would cause the tire to wad over itself. I run 15-15.5 without issue, and my sidewalls are still okay by the time the threads are showing.

It is not apples to oranges. Its physics, especially in a ladder bar car or Caltrac type car. The tire is "wadding over itself" because there is to much bite and not enough valving on the extension side of the shock. If it is a leaf spring car taking bite out is not so easy making valving even more critical. The MORE power a car makes and the faster said car is just exacerbates the issue. It's just physics, power does not change the physics of the issue just makes it harder to control.

My street car responds EXACTLY the same way, on a 10.5" tire running low 10's in Vegas at 3600lbs, as did my Belvedere running even slower. Control of the housing is what you need not more air. You mask the issue with more air because you are not controlling the rear end housing. Cheap shocks will not control the housing at all. Worked on every car I have been around and helped with. Starts with rear set up and shocks. The tires on the dragster have been on it for over a year and have 190+ laps on them.

The OP's car is actually a mid 9 second car, with ladder bars. The air in Vegas is not kind to ET's. I have watched the OP's car make a few passes and will GUARANTEE if he gets better control over the rear end housing with more extension valving the tires will be much happier and the car will be quicker period.

Topics like this really make me miss Monte.......

Al, all my old leaf spring cars would respond(go faster and quicker) to more air when I had let them down to low with 3400 Lbs. + plus cars on smaller tires bias ply slicks like 10.5x29x15 when they would shake from wadding up
Those where mid 11 to mid ten second cars
I've never let the tire pressure down low enough on my ladder bar cars or 4 link car to make the tires wad up like Mikes are 5.5 lbs. is not much air pressure

Cab you gotta have shocks to control the housing at the hit. Otherwise its a bandaid. We have had it down to 5lbs at times(had others lower) and as high as 7 depending on track conditions. But as I have said a few times if you don't have enough shock to control the housing, or if you have to much bite in the suspension not much matters. You need what it takes to get the car up on the tire quickly so it can accelerate quickly. That is based on track conditions and HP. We out 60' every car at our local bracket races by a good deal. Precisely because we pay attention and let the tire, chassis, and converter work as they are intended.

I also agree you want to run as much pressure as you can. I also agree in a bracket car it is much easier to KILL the tire to ensure it dead hooks. It aint fast but particularly in slower cars its consistent. In a faster car killing the tire is not consistent at all. Not saying you or anyone else needs to be at 5.5 lbs. Just stating the basic physics of whats going on and how it is controlled. Difference between a car running low 10's with a 1.4x 60' and a car running those same ET's with a high 1.2x 60'. All about efficiency

You are correct on that, my old cars had stock 50/50 shocks on the rear back then
We do learn, if we try hard enough and keep our minds open for help from others like you