Big HP guys running slicks, I need your advice...

Okay, so I made it to the track again with my 614 RWHP Z in my sig. I am running Mickey Thompson slicks mounted on salad shooter rims with about 16 psi in them. I am heating the Hell out of the tires, and traction off the line is decent, but in 2nd gear, and a little in 3rd the rear starts sliding out on me in the upper RPM's. A little bit I can handle, and will stay in the throttle, but what I am seeing, makes me too uncomfortable with it to stay in the gas. The slicks in general float around a little bit, and I am used to that, but I can't get used to the 2nd and third gear slide out.

Any advice here? Will heating the tires up further help? Perhaps with less pressure? Or is this just a standard thing I will have to adapt and overcome?

BTW, my best time was tonight with a 11.4 @ 128 with a 1.8 60" time. That particular run I was able to stay in the gas the hole way down, but didn't get a good launch.

With an all-out F-Body strip car, most people go to 15" rims for their slicks which adds much more side-wall w/ 28" to 30" diameter slicks. I believe you will have much better launches and control down the track w/ the more traditional slicks on 15" wheels. Basically, more side-wall equals better launches and more control.

I'm running 15" x 10" AlumiStar 2.0s with Goodyear 10.0" x 28" slicks and I have complete control w/ consistant 1.54 60ft times.

WD

http://shutter14.pictures.aol.com/data/pictures/06/008/31/FD/9C/0E/xpqn8YJ2dpALQUCA5ZBJ3LjowBeXlkys0300.jpg

Try running more 12psi.

Rich

Play around with it and make alot of passes. Seat time in the car will be the best thing.....try dropping the tires 1 psi at a time.....you want as much air in them as possible and still hook good

I agree that 15in wheels and tires would be better, but make sure your suspension is optimized so the tires can do there job better. Look at guys cars who are launching hard and see what they have, that will give you a starting point then you can adjust things to what your car likes the best I don't have the power you do but I have a good working car and probably wouldn't need to many adjustments to hook your power level.

Randy

I agree that 15in wheels and tires would be better, but make sure your suspension is optimized so the tires can do there job better. Look at guys cars who are launching hard and see what they have, that will give you a starting point then you can adjust things to what your car likes the best I don't have the power you do but I have a good working car and probably wouldn't need to many adjustments to hook your power level.

Randy

To get 60ft times like Randy (1.4s) and me (low 1.5s), you'll need the suspension set-up correctly. I have QA-1 90/10s up front, Spohn adjustable T/A, LCA relocation brackets, Air-bags and rear drag-springs.

WD

http://shutter05.pictures.aol.com/data/pictures/08/004/79/FF/00/AE/UDo7jjnWHPbG+TJzmme4WARD-P96oaaA0300.jpg

Thanks for the input guys. Trust me when I say my suspension is dialed in right already. I can get complete traction on the street in 1st gear with cold Nitto DR's even with my power level!

Just at the track with the slicks, I seem to be floating around a bit. I'll try dropping the psi a pound at a time, and get more practice in. One of the runs I spent a few extra seconds heating the tires up, and I dropped it at about 4300 RPM and it bogged! Once the RPMS picked back up, and I shifted into 2nd, the rear started coming out on me at what felt like about 40 degrees so I got out of it and decided just to coast the rest of the run.

BTW, I have QA1 shocks and drag springs, BMR upper and lower A-Arms, BMR K-member, BMR Subframe connectors, Hotchkiss LCA's, Sphon adjustable Torque Arm, ect., ect., ect.,.

loosen the front shocks for extension and tighten up the compression. At the same time stiffen the rear shock. Get the car to hold the weight transfer. Right now the car is unloading the tires. Also buy a 12 inch rim and solve all the rim issues. If you want 15 X 10's I have a set for you?

loosen the front shocks for extension and tighten up the compression. At the same time stiffen the rear shock. Get the car to hold the weight transfer. Right now the car is unloading the tires. Also buy a 12 inch rim and solve all the rim issues. If you want 15 X 10's I have a set for you?

lol, no thanks. I just purchased the slicks with the salad shooters, and thats what I'll be staying with. I'll also be leaving my suspension at its current settings as like I said before, it is dialed in for the street which is the main usage of the car (it is a street car more than anything).

I just need to figure out how to best run the car with its current setup as it is. Again, I'll try less tire pressure next time around. Mostly I think I just need more practice driving it as mentioned by someone earlier.

I might even try running on the DR's just to see how those do since I know they won't float around like the slicks do (although theoreically, they should spin more).

its easy to loosen the struts up......

So don't expect 100% from it if you want to leave it all set up as it is.

a 28" tire would hook better too.......I think your main problem is going to be driving it. Without a 100% set-up for the track it will be harder to drive, so make a lot of passes.....1/8 mile would work fine if you get your driving down to an art it should do pretty good.

But with the right susp. set up you could just drop it and ride!

I know it could be setup differently, and therefore better. But thats not what I am looking to do. I am trying to run the best I can with the setup I currently have (and the suspension where it is).

I do appreciate the inputs and the info. Any suggestions that doesn't include me changing my suspension settings or buying another set of rims and tires?

some of the BIG BIG h.p. street cars pull timing out the first 50-100 ft. so the caqr is moving before it shocks the tires....

Saw one a few weeks ago turbo car cut a 1.62 60" and went through the top end at 202m.p.h.

So maybe a timing retard or something like that

With that much tire pressure you could be riding the middle of the tire as they grow. Lower the pressure a bit. I like 10-12 depending on the track.

Well see the next time around how lower tire pressure does. With dropped tire pressure do you guys think it will stop floating and sliding so much?

Also, I have in car video of a couple of my runs so you guys can see exactly what I am talking about. I'll try to get the video posted up in the next couple of days.

What size are the slicks? Basically the goal is generally to have the footprint width equal the rim width. I have 15" x 10" rims and a 10" foot print. On the Mickey thompson website there is a range of rim widths for their tire sizes. I suspect you maybe mismatched. Forget ET and MPH and focus on the sixty foot time. You should be sub 1.5 easily with that hp in a normal environment. I think if you get the sixty foot ironed out the other shift points will likely fall into line as well.

You will not know about the rest of the suspension until you hook up. One problem at a time.

What size are the slicks? Basically the goal is generally to have the footprint width equal the rim width. I have 15" x 10" rims and a 10" foot print. On the Mickey thompson website there is a range of rim widths for their tire sizes. I suspect you maybe mismatched. Forget ET and MPH and focu on the sixty foot time. You should be sub 1.5 easily with that hp in a normal environment. I think if you get the sixty foot ironed out the other shift points will likely fall into line as well.

You will not know about the rest of the suspension until you hook up. One problem at a time.


I agree, his 1.8 60fts are weak for the amount of HP he is making, they should be down in the low 1.5s, or 1.4s (a gain of 3 to 4 tenths in the 60ft alone). And as I mentioned previously, slicks on 15" rims with more side-wall are far superior to the low-profile slicks on 16" rims.

WD

What exactly is your tire setup?
ET streets?
ET drags?
What size?
What front tire are you running?
How much air in the fronts?

Off the top of my head, I don't know the exact size of the tires. I just know they are the Mickey Thompson ET streets mounted on the salad shooter rims. I'll go out to my shed later today and get the exact size for everyone.

Again, I am sure you guys are right, and I already know I could better my times with a smaller rim, and bigger slick. But thats NOT what I am looking to do here. I simply want to get the best out of what I CURRENTLY have.

BTW, the front tires are Nitto 555R's (275/35ZR18) at between 30-33 psi.

Alright, I just checked the tire size of my Mickey Thompson E/T Streets. They are 26X10.50 - 16CT

BTW, the video of the track runs is currently being uploaded. Once the server has completed uploading it, I'll post it up.

Off the top of my head, I don't know the exact size of the tires. I just know they are the Mickey Thompson ET streets mounted on the salad shooter rims. I'll go out to my shed later today and get the exact size for everyone.

Again, I am sure you guys are right, and I already know I could better my times with a smaller rim, and bigger slick. But thats NOT what I am looking to do here. I simply want to get the best out of what I CURRENTLY have.

BTW, the front tires are Nitto 555R's (275/35ZR18) at between 30-33 psi.

You probably have the 26-10.50x16 and you're already getting all that you can from that size of tire. It's just plain not enough tire for your hp level. Heck they are not enough tire for my hp level unless the track prep is good.
Pumping the fronts to 44 psi will help with the top end sashey.

Well, on another pass I made later in the night, I spent a few more seconds heating the tires up, and when I dropped the clutch at 4200-4300 RPM it bogged the motor because it bit so hard! But then after 1st gear got back up to the upper RPM's and I shifted into 2nd, the car started sliding sideways again and I got out of it.

Here's the video. As you can see, once the car is moving, it is difficult for me to keep it straight as the back end floats side to side. The first run I was able to stay in it to get a decent pass. The next run (and pretty much the rest of the runs that day) the back got a little too far out for me to feel comfortable to stay on the gas. The video made the sliding and floating look more tame than how it actually feels in the car. Is this normal for slicks? Do I just need to get used to this? Or is there a way with running different tire pressure or something (possibly better track prep) that will help the floating out?

http://thumbs.vidiac.com/ed7adb81-4d7d-4516-9d7a-996200e941e0.jpg (http://videos.camaroz28.com/video/ed7adb81-4d7d-4516-9d7a-996200e941e0.htm)Click here to see Video (http://videos.camaroz28.com/video/ed7adb81-4d7d-4516-9d7a-996200e941e0.htm)

You need to run skinnies up front. Bias ply and radials don't mix.

Go to bias ply up front or at least skinny radials (VW etc) and your sway will go down dramatically. Your 60 will also improve.

A couple of the earlier posters have already beaten me to the punch on this one, but, you are running one of the worst front/rear tire combos for "floating and top end sway", (as you refer to it), that you possibly could. :( You're attempting to run 16 psi of air in a bias ply 26x10.50x16 rear tire....(with 600+ RWHP I might add)....and 275/35/18 radial tires up front. :eek: As suggested above, if you change out those wide radial front tires for a pair of 4.5"/5" wide bias ply skinnies, I'd bet 95% of your "float and sway" would be gone. Conversely, a pair of MT 275/50/16 drag radials on the rear would also reduce float and sway considerably. I know you just purchased those rear bias ply slicks, but...... something's gotta give here. :confused:

Well, perhaps my setup is not ideal, but it is what it is. Like I have mentioned REPEATINGLY, I don't plan on changing the setup from where I am at, as it is idealy setup for what I mostly use it for (street use). I probably won't do skinnies up front either as I have very large aftermarket Baer brakes that most skinnies won't fit on anyway.

Is it possible if I raised the psi in the front tires that I would help the floating as mentioned by someone? Also, will a simple change in psi for the rears help as well?

raising the air won't do anything........


If your not willing to change anything than you will just need seat time.......make alot of passes.

Try not to wreck it......at that power level, its smart to have an ideal set-up to get you down the track

Try not to wreck it......at that power level, its smart to have an ideal set-up to get you down the track

lol, thats the #1 priority, not to wreck it. It's used and enjoyed as a street car too much for me to change it up. This was still only my second time to the track with that power level and the slicks, so perhaps more seat time will be the key.

It is not really an air pressure problem. Air pressure and susp can mask the problem or lessen it, but the problem will still be there.

When you have stiff sidewalls on one half of the car and flexible ones on the other half it will cause instability. It happened to me any everyone I know that has run your identical setup. The swap to skinnies is like night and day.

I can see your problem though, as big brakes make skinnies near impossible. If the big brakes are more important than skinnies, your only real fix for the problem is to swap to drag radials in the back. Radials will likely be harder to hook for you, but they will fix the sway.

At one time I was using ET Streets on salad shooters with 16" high performance radials on the front and had no stability issues. The last combo, before retiring the car from the strip, was a 15" slick on the rear and high performance 17" radials on the front. No stability problems with that combo either.

Rich

I don't think your solution has anything to do with the front/rear tire combination. You're simply breaking-loose those small 26" ET Streets with the HP your car has. And you'll probably always be in the "danger zone" to some degree running those small 26" ETs at the track. And, you’ve pointed-out that is your wheel/slick preference and don’t plan to change.

For example; when I had a 12.40 car (cam and bolt-on's), I also ran 16" rims and the 26" ET Streets. Sometimes when I shifted to 2nd the ETs would break loose and the car would get a little scary.

However, now with a low 11 second car and the correct wheels and slicks, the car never gets loose.

WD

At one time I was using ET Streets on salad shooters with 16" high performance radials on the front and had no stability issues. The last combo, before retiring the car from the strip, was a 15" slick on the rear and high performance 17" radials on the front. No stability problems with that combo either.

Rich

You never felt any sway? Even in the 100+mph range?

What kind of pressure were you running? Did you have full suspension? Cage?

I'm not doubting you, my experience has just been different. My car was virtually stock suspended with the addition of ET streets. It swayed as soon as I put them on. I can think of at least 4 other racing friends that mentioned exactly the same thing.

Some of the sway could have just been newbies to the feel of a bias ply tire. But from my experience (all be it far less than many of the posters in this thread) slicks and radials together = sway.

You guys just aren't used to bias ply tires......

Rich is one of the most experienced guys on this board. I trust what he says over most.

Rich is one of the most experienced guys on this board. I trust what he says over most.

I wonder how much HP Rich was running with his 26" ETs (and had no problems), in compairson to your current setup?

WD

I believe he may be running more power than me.

convert to an auto :D

You never felt any sway? Even in the 100+mph range?

What kind of pressure were you running? Did you have full suspension? Cage?


I ran the ET streets with street radials out front for a couple of years with no sway at all. But as I said in a previous post I put the air in the front to the manufacturers maximum to make them as stiff as possible and to make them run on just the center tread. But I never ever ran less than 16 psi hot in the ET streets as per Mickey Thompsons recommended minimum.

I don't think your solution has anything to do with the front/rear tire combination. You're simply breaking-loose those small 26" ET Streets with the HP your car has. And you'll probably always be in the "danger zone" to some degree running those small 26" ETs at the track. And, you’ve pointed-out that is your wheel/slick preference and don’t plan to change.

For example; when I had a 12.40 car (cam and bolt-on's), I also ran 16" rims and the 26" ET Streets. Sometimes when I shifted to 2nd the ETs would break loose and the car would get a little scary.

However, now with a low 11 second car and the correct wheels and slicks, the car never gets loose.

WD


Exactly. I'm currently running 275-60x15 Hoosier drag radials and have zero traction problems.

I ran the ET streets with street radials out front for a couple of years with no sway at all. But as I said in a previous post I put the air in the front to the manufacturers maximum to make them as stiff as possible and to make them run on just the center tread. But I never ever ran less than 16 psi hot in the ET streets as per Mickey Thompsons recommended minimum.

Were you running your ET Streets (possibly 26") on 16" rims w/ low-profile side-walls?

WD

The 26" ET Streets are going to have a harder time holding that power than the ET Drags... why not get a pair of those? You can't drive either of them in the rain, so neither are really "street tires" in my opinion. :shrug:

Also, the increased sway up top is due to you not running skinnies up front (actually it's due to you running such a wide tire up front).

If your car isn't setup properly for drag racing, don't expect it to drag race well. :shrug:

Mike

There's a right way and a wrong way to go about this. Guess which one you have.

If your not willing to change why did you ask the question?

Randy

lol you guys crack me up. Can't a guy ask how to do the best with his setup and get answers that don't include "change your setup"? Like I said, the car is used more on the street, and I just wanted to see if there was something I should know about running with what I have, or maybe utilizing what I have better thats all.

You never felt any sway? Even in the 100+mph range?

What kind of pressure were you running? Did you have full suspension? Cage?

I'm not doubting you, my experience has just been different. My car was virtually stock suspended with the addition of ET streets. It swayed as soon as I put them on. I can think of at least 4 other racing friends that mentioned exactly the same thing.

Some of the sway could have just been newbies to the feel of a bias ply tire. But from my experience (all be it far less than many of the posters in this thread) slicks and radials together = sway.


I can't say it was stable as a rock. But nothing alarming. The car has 1LE springs/shock/and swaybars along with a Spohn torque arm and tubular LCA's. I was running over 140mph and like I said, as long as you stayed straight, no problem. If the car got out of the groove, it was best just to shut it down. Of course, that is pretty much true with any car running that quick.

Rich

lol you guys crack me up. Can't a guy ask how to do the best with his setup and get answers that don't include "change your setup"? Like I said, the car is used more on the street, and I just wanted to see if there was something I should know about running with what I have, or maybe utilizing what I have better thats all.

You also crack me up! Apparently you’re looking for the answer you “want to hear” (that those small 26” ET will work just fine) while rejecting the answers you really “need to hear” (bigger slicks to handle your HP and not break loose). And, you only use the slicks at the track, therefore it doesn't change your street package.

For example; when Rich implied the 26” ETs should work without any problem, you immediately cited Rich’s credibility on the matter, whereas about twenty other people told you they were too small for your HP and you discounted those inputs.

I sure hope someone on the forum will be able to provide you with the “magic set-up” to make those 26” ETs work for you without getting your car unstable when you break them loose at the track! Then you'll have the answer you're looking for. Good luck!

WD

:bang: :shrug: :blahblah: I dont see this thread going anywhere. he wants help and others opinions. but doesnt want anyones help or opinions. his suspension is dialed in 100%. but the car wont go down the track safely:confused: . I just dont get it? what seems to be the problem???

ps I dont mean to offend anyone

I trust what Rich says, and I also trust what everyone else is saying. I never said I don't believe what all of you are saying is true. But you are right, I am not going to take the advice, because it doesn't answer the question I asked specifically.

I wanted to know with my current setup if this swaying was normal, and if there was anything with keeping my current setup that I could do to help me. It's kind of like asking how do I keep my car stock, but get a better time at the track and everyone is saying "add mods to your car" and then getting upset with me for wanting to keep it stock.

I don't want this thread to turn into one of those argumentative ones. I'm not upset at anyone here, and hope I haven't upset anyone either. But please understand what I am asking.

But please understand what I am asking.



What your trying to do...seems similar to me to a 10.5" tire class race car....

1. your over powered
2. your restricted by your tire


Before you try to tweak little things....you need to make alot more passes, because you can't drive it. You have to find the sweet spot in the clutch/launch so it leaves but doesen't overpower the tires. Go to some test and tunes and just leave on it.....no need to make a bunch of full passes.

Like someone said if you get it to leave good it will sail down the track nice and smooth.....
You see a pro mod leave? when they shake its over......when it comes out the hole good it goes smoothly.


My buddy has a N/A mustang...460 BBF 3 speed lenko, they spent 3 months and ended up having to take it to someone else to get the car to leave on a 10.50 tire at 1100 h.p.

I say if you drive it alot more you will get better. I drove a car once and went a 10.0.......let a good driver drive it and it went over a second quicker.

Just go to the track more........Good luck

Thanks. The car seems to get out of the hole pretty good each time. It's just when the RPM's get up past 5500 RPM or so, thats when the back starts coming out.

One launch I spent a few extra seconds in the burnout pit, and when I dropped it at 4200-4300 RPM it bogged! But once the RPM's got to the top it started spinning again.

turn down the boost then.....get it to where you have as much power as you can use.

turn down the boost then.....get it to where you have as much power as you can use.

Well, its not a turbo car, so adjusting the boost isn't really that simple. I might try shifting a little earlier though and see if that helps.

Mine was much easier to drive with the TH400 than with the M6. An auto with a race converter shifts very smoothly - you can hardly feel the shift. Are you trying to powershift it?

Rich

yea auto's are nice for the 1/4 mile :)

Nope, just shifting quick as usual. No powershifting.

I watched the video. The tires you specified have only an 8.4 inch footprint. ET Streets are measured at the sidewall so they have a small contact area for the weight and power level of your car.

The weight is transfering so I suggest adding some airbags to stiffen the rear a bit (cheap).

You need to work on your shifting as you are losing lot of ET at your shift points. It takes a lot of practice to become proficient at shifting.

Yeah, I need more practice at the track all together.

I am having the same problem as you but not quite making the same HP. I have run the 16" et streets and the 16" drag radials and nothing has worked. My thinking is if you are able to launch good off the line and your tires are breaking loose up top then nothing will help that except a change. As I understand it, suspension and air bags are mainly used to get you off the line. However, you dont seem to have a problem there just need more seat time to get a consistant launch

I am having the same problem as you but not quite making the same HP. I have run the 16" et streets and the 16" drag radials and nothing has worked. My thinking is if you are able to launch good off the line and your tires are breaking loose up top then nothing will help that except a change. As I understand it, suspension and air bags are mainly used to get you off the line. However, you dont seem to have a problem there just need more seat time to get a consistant launch

Good observation, as that does in fact seem to be the issue. I might try to combat this by shifting at a lower RPM (at least for the first few gears).

That seems to be your only option without changing anything