Another ATX question

[expy916]

Car:1993 ATX(optionless, except for seats)
Mods: 96 brakes, Eibachs, CAI, 80mm MAF, LPM, D4U1


It currently has some older Eagle RS-As.(225/60)

I have a pair of newer Toyo eclipses(225/60), and a pair of newer Federal Formozas(225/60) on my mtx.

Would it be worth the effort of switching the tires from my mtx to my atx? If so, which set?

I am already going to be putting blocks in the back and dropping the front more. And removing the spare tire. Any other recomendations?

Also, is 15.1 a reasonable goal?

 

[hawkeye18]

with sticky tires and a healthy engine, 15.1 is doable. You might lose some speed due to the higher effective gear ratio of the 60 series tires. You might wanna drop down to a 55 or even 50 to see lower trap times. But if you have 60s, then you have 60s. I'd say lower the pressure up front and let 'er rip.

You might wanna remove the passenger seat for an easy 60 pounds gone.

 

[expy916]

Which ones are stickier? Toyos or Federals?

 

[hawkeye18]

Couldn't tell you lol. I don't know the first thing about either tire. Sorry...

 

[somedude_001]

I would be expecting mid 15's with what you have on a ATX. The ATX does have torque management on it from the factory so if your chip has that removed you should be able to pull a impressive 60' time and that might get you low 15's. The ATX has a taller gear ratio than the MTX and that does slow it down quite a bit in the 1/4 mile.

I am not familiar with those tires so I don't have any input there.

 

[VortecGT]

I know this is off topic but was it worth it to swap computers? Can you notice any difference?

 

[expy916]

Yes, shifting was amazing, Just wait for a sale at your local jy, or get a "discount".

 

[hawkeye18]

Oh yes, you should definitely switch computers. The D4U1 makes your '93 transmission much less blow-up-happy. And it shifts a million bazillion times better.

 

[Ian Macoomb]

In my experience with my V8 you're best off with the worn RSA's. The RSA's are really light. Especially with most of the tread worn off. Unless it's really cold you shouldn't have much wheelspin. In fact you want a bit to keep the car from bogging. Run with as little fuel as possible. If the engine is healthy you could see low 15's.

 

[expy916]

Oh yes, you should definitely switch computers. The D4U1 makes your '93 transmission much less blow-up-happy. And it shifts a million bazillion times better.

Actually, a trillion billion E^57

In my experience with my V8 you're best off with the worn RSA's. The RSA's are really light. Especially with most of the tread worn off. Unless it's really cold you shouldn't have much wheelspin. In fact you want a bit to keep the car from bogging. Run with as little fuel as possible. If the engine is healthy you could see low 15's.

Its going to be a cool day. Max 76 and low 47. %48-%65 humidity.

True, the RSAs are light, but they are HARD! Half throttle from a dead stop, and they chirp.

The Eclipses are slightly taller than the Formozas, but also wider(like the RSAs), and softer.

 

[38SHO]

. The ATX has a taller gear ratio than the MTX and that does slow it down quite a bit in the 1/4 mile.

I thought the final ratio was in the 3:72-3:74 range for both the atx and mtx

or are you talking about the individual gears?

 

[somedude_001]

I thought the final ratio was in the 3:72-3:74 range for both the atx and mtx

or are you talking about the individual gears?

oh i just looked it up on TCCA and you are right the final drive is very close. The individual gears on the ATX is suited very well for a high power (boosted) car but not so much for a stock SHO. I think the gearing with my 3.98 setup in my ATX is pretty ideal for the power I was making. I am mostly comparing traction VS power. I cannot spin hot sticky R compound tires at the drag strip. there are other factors working there too there but I don't want to derail the thread.

When my car was completely stock I would bump the revlimiter in seccond gear as I crossed the finish line. In my opinion a 3.98 gear ratio swap would make a other wise stock SHO slower in the 1/4 mile because of the added shift.

Just go hammer the snot out of your car. When I used to race my car stock I would run high pressure in all 4 tires to decrease rolling resistance and I would also move the passenger seat all the way forward to get more weight on the front wheels for traction. I can't honestly say it helped any but it was fun.

 

[expy916]

I haved searched, and gotten a lot of yes and no answers.
Will a 235/50/16 tire fit on a slicer? I dont care how it looks(bulging) or how it handles. Does it fit?

 

[Ian Macoomb]

Somedude, are you sure about being in 2nd as you crossed the line? My Gen 3 would be in 3rd by the time I hit the 1/4 mile mark. I can't see another shift making that much difference in an automatic. Especially if you up the shift pressures with a tuner.

And to answer the other question. A 235 might fit on a slicer but I would bet it would depend on the tire installer. Some tire guys might not want to.

 

[expy916]

My tire guy doesnt give a crap, as long as he gets paid, and I'm happy, he's happy.

 

[hawkeye18]

a 235/50 runs about a 50% chance of fitting. Even if it did fit, I'd be really concerned about the bead popping off the rim because it's at such a high angle. It would, of course, do this mid-turn.

 

[expy916]

Is 235 worth the traction? or would I be better off getting some 225/55 or 50?

 

[somedude_001]

Somedude, are you sure about being in 2nd as you crossed the line? My Gen 3 would be in 3rd by the time I hit the 1/4 mile mark. I can't see another shift making that much difference in an automatic. Especially if you up the shift pressures with a tuner.

And to answer the other question. A 235 might fit on a slicer but I would bet it would depend on the tire installer. Some tire guys might not want to.

yeah. my car trapped 88.9mph when it was stock (no tuner or anything). it would hit the revlimiter 2 or 3 times then cross the line. it was dead consistent. The third gear shift use to take FOREVER so I didn't bother with it because I would drop mph if I let it shift. If I would have had the tweecer back then it may have been a different story.

 

[hawkeye18]

Honestly the engine can't generally provide enough grunt down low to break 225's, which is what I've always run. A 225/55 is very close to stock overall diameter, and the 225/50 will of course give you an overall gearing increase which will make it accelerate faster. A 225/50 is not the easiest thing to get on a slicer rim - i've done it, but it took a long time. A 225/55 is easier.

 

[expy916]

I can break them loose all the time

I'll just throw the eclipses on.

Whats a good tire pressure?
Is there an "overkill" limit on RPMs for the launch(brake torque) or do I just do it from as high as I can?