Ok after swapping on the Nitto Drag radials the car hooks great but there is more wiggle in the corners and emergency lane changing. I miss the feel that my RE730's had on the back tires. They planted really well with little wiggle.
The car is built for drag racing and road racing while being fairly streetable.
Will a 21mm 1LE hollow bar be a good choice in stabalizing the rear? Im putting a Solid 32mm bar up front with the Bridgestone RE730's. Am I on the right track here to making it handle better on the street?

Also considering Bilstein HD's but they are on back order. Its a cost thing.

Suppension/ tire mods include, SS 17x9 rims, re730's, subframe connectors, LCA's, panhard rod, stb, 32mm solid front sway bar.

 

Could just be a weaker sidewall, which drag radials usually have by thier nature, but I thought that some actually said the Nittos were "good" in a handling car, to what extent "good" means "good" I dont know.

Adding a rear bar wont change wiggle, just balance of the car.

What exactly is 'wiggle' though? Like a high frequency shimmy?

 

Good as in awesome grip in both straightline stuff and cornering (suprisingly). Probably not as good as a Hoosier but still light years ahead of a street tire. They also dont seem to heat cycle as fast a dedicated race tire so they'll age better.

The downside is their flimsy sidewalls, for auto-x you can just pump up the pressure a little more but that will wear the centers out if you try it on the street.

IMO if handling was your primary concern then you should have tried the 555RII. Its the road race version of the drag radial, same compound just a stiffer sidewall.

 

"Will a 21mm 1LE hollow bar be a good choice in stabalizing the rear? "

No. If your rear is wiggling now, a bigger rear bar will make it wiggle _more_.

Changing sway bars is a hard mod to get right, requires a lot of knowledge.

 

Well i dont have a lot of knowledge when it comes to suspension. The wiggle is most likely the nitto side wall giving and coming back into place. I need the drag radial. I dont hook up without it. I'd rather go faster than handle better but I still want to handle better. Its like making a hard emergency lane change, the sidewalls go the opposite direction while the car is moving one way.. when the car straightens out the sidewalls move towards the cars direction and over does it and goes to far, then they come back to center. Thats what i mean by wiggle.
How do i know what sway bar i want. Ive read the other threads and there is no clear answer. Why does a 1le have the 21mm bar and the SS's with the suspension package have the 21mm bar? If it weren't good then why put them on?

 

If you had 245s or 275s before, all equal and the car handles ok, and then upgraded to the same tires before or the same adjustment of +30mm on both front/rear or etc, a bar isn't going to make things better.

If the sidewall is soft more PSI on the fun-track may help, then drop back down for the quarter. Whats your current PSI front/rear? Maybe that will give someone an idea where to go.

IMO handling is going faster, quarter mile is going quick, and finishing quick.... snooze

 

The only "real" solution for getting rid of your 'wiggle' is to get another set of wheels with the right tires on them and slap on your drag radials for the trips to and from the drag strip. A harder bar makes the inside wheel want to lift off the ground under hard cornering. If you're already getting a 'wiggle' now, just emagine what is gonna happen when your inside tire tries to lift during that wiggle. Do you like merry go rounds? If you have tires that grip as good sideways as they do front to back, you might try a sway bar in the rear. But it's not necessary. From autocrossing, I've found that you put a soft bar on the 'driven' wheels and a stiff one on the others. That's why VW Golfs can lift a rear wheel 6 inches off the ground in a tight corner. Stiffen springs before you stiffen the bar though.

 

"Why does a 1le have the 21mm bar and the SS's with the suspension package have the 21mm bar? If it weren't good then why put them on?"

Here's the deal. The two swaybars and the four springs all have to work together and must be carefully matched. Changing just one swaybar won't necessarily help anything and can actually hurt.

In particular, a larger rear swaybar will make the rear end handle more of the cornering load. So, if the rear tires are already not handling well, a larger rear bar will make that worse.

BTW, GM dropped the 21 as "1LE' right after they tried them in 93 and went to a 19. SLP's SS pairs the 21mm rear with a 35mm front. Both the 1LE and the SS use different springs, of course.

"How do i know what sway bar i want. Ive read the other threads and there is no clear answer. "

Swaybars are a really tricky deal, although many posts here would have you believe otherwise.

"From autocrossing, I've found that you put a soft bar on the 'driven' wheels and a stiff one on the others."

And the reason early Porsche 911s have very stiff front bars and soft rear ones is....? They pull the _front_ wheel in a hard corner.

This is a tricky deal.

 

Sounds like what you need to do is increase the lateral stiffness of the tire, and about the only way to do that (still keeping the DR's) would be to mount them on wider rear wheels. 255's on 10" wide rims instead of 8.5" or 9", 275's on 11's instead of 9's or 10's, etc.

Norm

 

Do you have 16's or 17's??? I have been running DR's for years and do not feel that the 17's "wiggle". The sidewall isn't as stiff as a Kuhmo. What shocks do you have? I would almost bet what you are feeling is the shocks unloading.

 

My bilstein HD's are in the mail (not back order ) so we'll find out. I run 17x9's 275/40/17's all the way around. PSI is set at 35 for the nittos.
Its not bad per say but its not as good as it was. Im just trying to find a way to improve it while keeping the drag radials. I suppose i could add some more psi's to the nittos...
What PSI do you guys have yours set at?

 

Only thing you can really do is add some pressure to the tires. Upgrading susepension components is wasting money if the problem lies in the tires themselves.

I know this wiggle, I have it big time when on my ET streets, feels just like your rear tires are going flat. Add some pressure to effectively stiffen the tires but the only real solution is to get good street radials and swap to the DRs at the track only. This is why I skipped nittos and went straight for ET streets...if you're only going to run them a few times a year you might as well not compromise. This actually can save money in the long run by saving your street tires from the wear and tear of repeated burouts and dragstrip launches.

 

I run my Nitto's at 27 rear and 32 front, even for autox. Any more pressure than that and you aren't using the whole tire, and the center will wear out long before the outside.

 

Nitto makes a roadrace tire called the NT-555R2 thats supposed to be pretty good. Its sidewall is stiffer for turning. I think this is the tire that most people are refering to when talking about Nitto and RR (Also the Nitto TR-555 is a good street tire).

--Kevin