Fox Drag Radial Help

[RangerJoe]

Well, I have heard it said before; changing one small thing can change a host of others. I bought a used set of Mickey Thompson ET Street Radial Tires last year (235/60/15). They had a little more than half their life left. I mounted them up, but just now put them on the car today (trying to get ready for NMRA Commerce).

Other changes include going from a Eibach lowering spring in the rear to a set of cut, stock coils. On my 555R's could never launch more than 3000rpm. I expected with the MT's to let this sucker go about 4000 or so. So I took it out today, did a 1st gear burn out, and launched at 3500rpm. The result, massive tire spin.

So, I try to do a 2nd gear burn out, end up smoking my clutch in the process (hope it will hold out through NRMA, fingers crossed). I launch at 3500 again, and another massive dose of wheel spin.

A couple of things I have not done:
-Reset my pinion angle
-Played with my adjustable shocks
-MT's had 20psi in them (driving on the road)

So, any advise here? I thought these things would be hook city, but no success yet. I don't have a lot of free time between now and NMRA. Someone point me in the right direction. Can drag radials go bad from sitting up? They have been inside out of direct sunlight.

Joe

 

[Gearbanger 101]

I always had best results when running my ET Street Radials closer to stock tire pressure. 28-30psi worked best for me.

No need to burn them off the rim with your burn out either. Give them a 3-5 second peel and the drive out of it.

The more worn a tire is, the less it's gonna hook, so you might just be at the point with these tire's that they're not going to take a dead pedal clutch drop any more. Consider "letting the clutch out" instead of dumping it.

Those tires hook like mad when new. I made 465lbs/ft with my Cougar and could barely get them to break traction out of the hole. Great tire.

 

[84Ttop]

If you adjusted the ride height then you need to check the pinion angle
I have seen the most success with these tires between 16-18 lbs of air pressure
How old are the tires? After they are any more than a year old they start to get hard.
Burn out on ET radials just till they start to smoke and that's it.
Remember.... you are trying to do this on the street. The track can and probably will be a totally different story.

 

[RangerJoe]

If you adjusted the ride height then you need to check the pinion angle
I have seen the most success with these tires between 16-18 lbs of air pressure
How old are the tires? After they are any more than a year old they start to get hard.
Burn out on ET radials just till they start to smoke and that's it.
Remember.... you are trying to do this on the street. The track can and probably will be a totally different story.

Definitely have to work on the pinion angle. And yes, they are more than a year old. I have had them almost a year, and I bought them used. So, I may have wasted my money. Is there anything I can do to soften the compound up? I've heard about WD40 maybe? Don't laugh, I have seriously heard this.

Joe

 

[srtthis]

VHT if anything to soften them up


the idea with a radial is to hit it hard and keep the power to it. so from other then seeing a video i cant really give you a ton of suggestions. i launched my at 4500 off the 2step and pretty much just let the clutch out as fast as i could with out side stepping it

 

[90lxcoupe]

With a radial and a stick you have to slip the clutch. Like SRT said, if you hit the tire hard and you dont keep power to it they will unload and spin. I think if you had a fresh set they would work a little better but no radial tire is going to just stick on the street dumping the clutch unless the car is way underpowered.

When you go to the track try slipping the clutch till at least half way thru first(it goes by quick). If you just dump the clutch the car is either going to hook and bog, blow the tires off, or hook and unload the tires and spin.

 

[srtthis]

With a radial and a stick you have to slip the clutch. Like SRT said, if you hit the tire hard and you dont keep power to it they will unload and spin. I think if you had a fresh set they would work a little better but no radial tire is going to just stick on the street dumping the clutch unless the car is way underpowered.

When you go to the track try slipping the clutch till at least half way thru first(it goes by quick). If you just dump the clutch the car is either going to hook and bog, blow the tires off, or hook and unload the tires and spin.

that was my issue... i tried a few launches at 6250 to get it to power thru the bog but i couldnt get the clutch down right.

 

[7upstang91]

There is a reason they were sold at half life...

 

[gearheadboy]

I have a set of year old ones that are NEW tread wise. They work fabulous. I think the track will be your friend. I launch mine on the local concrete overpass and they dead hook. On black top is a little different.

 

[bentley429isBAC]

What were the road conditions? Asphalt or concrete? Air and road temp? All of that matters. 84, srt, 90lx all have good input.

 

[rbohm]

here are a couple of threads you might want to read about trying to soften up drag tires;

http://forums.corral.net/forums/drag-racing/762345-chemically-softening-tires.html

http://www.jalopyjournal.com/forum/archive/index.php/t-131157.html

at the track you might also drop your tire pressure to about 12-14psi.

 

[RangerJoe]

I've run another brand drag radial before, nittos. I had launching them at track and on the street down fairly well. The same technique did not work out so well with the MT's. I will work on pinion angle and perhaps try a lower air pressure. I like the concrete overpass idea.

Joe

 

[flstang65]

Sounds like your springs aren't allowing for proper weight transfer eaiter

 

[RangerJoe]

What were the road conditions? Asphalt or concrete? Air and road temp? All of that matters. 84, srt, 90lx all have good input.

Asphalt road, about 65 degrees air temp, no idea what the road temp was.

Sounds like your springs aren't allowing for proper weight transfer eaiter

175lb coil overs up front. I just swapped to the stock springs into the rear hoping to get my 60ft times down. They are supposed to be the stuff these days. I will give it another go, I was just surprised at how well they did not stick. I mean, I think my 555R's were sticking better than this when I had them on. But like I said before, the changes I made may have thrown the whole combination off.

Joe

 

[flstang65]

555r's are AWESOME street tires. Inconsistent at the track. I could cut a 1.80 60' and the next pass 2.0+. the best times I ever had were with my stock springs in the back and 4cyl springs up front when I was running on a super tight budget.

 

[gearheadboy]

I do have adjustable rear lower arms and drag springs all around too. It transfers nice. I also have a little softer clutch than most people.

 

[A5literMan]

555r's are AWESOME street tires. Inconsistent at the track. I could cut a 1.80 60' and the next pass 2.0+. the best times I ever had were with my stock springs in the back and 4cyl springs up front when I was running on a super tight budget.

This is what I've found to be true with my 555r's also. Like them for the street but inconsistent at the track. I really really tried to find the sweet spot and then repeat the exact same process every time. I finally cut a 1.80 60ft. Went back after a slight cool down and ran 1.95-2.00's. Irritating. Have probably 15 passes in them and they never are consistent. Now Im changing my suspension and want to go to MT Pro's with weld rims. Hopefully I can get it down to 1.5 or so and get some consistency

 

[f8tlfiveo]

When you go to the track try slipping the clutch till at least half way thru first(it goes by quick). If you just dump the clutch the car is either going to hook and bog, blow the tires off, or hook and unload the tires and spin.

Or hook and break an axle... Been there done that on nitto 555r tires that were close to 8 years old. They were kept in a barn out of the sunlight for most of their life though.

 

[RangerJoe]

A little update. I got my ride height worked out and set my pinion angle (-2 degrees) and adjusted my shocks. I also adjusted my clutch and drove the car a little, trying to change gears as often as possible to give the clutch a chance to maybe wear down any glazing that might have occurred. I tried 3500 again and had a little better success. Still spun, but I think that can be worked out on a prepped track with a good burnout and air pressure adjustment.

Everyone says hit the tire hard a keep power to it. This is my current technique:

I raise the rpms until they bairly bump the 2 step, no leaving off the floor. I release the clutch, no side stepping, any start matting it as the clutch grabs. This is how I did the 555rs and how I am trying to do the MTs.

Now, Would I be better off leaving lower, say 2500, and having the gas on the floor coming off the 2 step? 3500 is pushing the traction limits, would it be better to hit them a little lower in the rpm range and have the power instantaneously ramping in on top of them?

Hopefully someone can follow my logic here.

Joe

 

[srtthis]

I'd hit them as hard as you can... 6250 and hold the on lol.