Pro Touring bar problem

[UNGN]

First, I have to say that the handing with the pro touring bar is great. I was going into and coming out of corners 10 mph faster than with the Herb Adams bar I'd had in the car for 10 years, mostly because the suspension was absorbing the bumps instead of hopping over them.

but... after easily averaging 148 mph for 30 miles and backing off to cruise at 120 mph to get my average speed back to 135, the car started filling with smoke, coming from the back of the car.

It turns out that the Huge Herb Adams rear swaybar we had also helped triangulate the LCA's and locate the rear axle laterally... and the axle shifted 1.5" to the right, destroying the outside of one tire on the fender and melting the inside of the other tire against the frame. It looks like one of the adjustable uppers may have loosed up, but they were just tightened a month ago.

I'm beginning to think Adjustable uppers are pretty stupid on a car that is driven more than a 1/4 mile at a time and they are going to get pinned.

So it turns out, if you install the PT rear bar, unless you put in a panhard bad or a fayes2 watts link DON'T put in Spherical LCA/UCA joints and especially spherical adjustable uppers, unless you are running 215 wide tires.

Who'd have thought binding was good?

 

[BlackMetal]

Wow that sounds like a nasty hishap.

 

[UNGN]

Here's a picture of us going 166 mph (this picture was taken in the "official" speed trap). I have one hand on the wheel so handling is great. The only indication of 166 mph is the side windows are sucked out 2" by the wind rushing over them They pop out about 145 mph and come back below 130.

 

[charlief1]

Oh HE!! IT'S YOU!! I saw one of your runs a few years ago and it was SWEET! Nice job. You don't want the adjustable tops you need the adjustable lowers with rod ends for sure. I'ts late and I'm just about to go to bed but I'll get back to you tomorow. Other than the supension mods what else have you done?

 

[IrvJr]

That wouldnt happen with a stock replacement set of tubular control arms, would it?

 

[UNGN]

That wouldnt happen with a stock replacement set of tubular control arms, would it?

If you have wide tires and plan on going around corners fast with them and it rubs a little with a ATR or stock bar, I'm pretty sure it will rub more around corners with the pro touring bar.

When we get everything fixed and put back togther, I'm going to tape some paper against the frame to see if the tires mark it going fast around on-ramps.

 

[charlief1]

If you have wide tires and plan on going around corners fast with them and it rubs a little with a ATR or stock bar, I'm pretty sure it will rub more around corners with the pro touring bar.

When we get everything fixed and put back togther, I'm going to tape some paper against the frame to see if the tires mark it going fast around on-ramps.

Since you're having a problem with rear end movement then you need something to keep it centered. A watts link is the most secure and keeps the rear centered. As far as a panhard bar you will still get some movement as the supension moves up and down but it's a trade off. Weight versus control I'd take control personally. If you change the offset of your tires you might be a little better off but then you have the lip on the fiender to deal with. Tell me what you've done as far as the rear to keep it under control please.

 

[rmar]

The only indication of 166 mph is the side windows are sucked out 2" by the wind rushing over them They pop out about 145 mph and come back below 130.

So your car is equipped with automatic AC.
Or speed rated climate control........:biggrin:

 

[UNGN]

Since you're having a problem with rear end movement then you need something to keep it centered. A watts link is the most secure and keeps the rear centered. As far as a panhard bar you will still get some movement as the supension moves up and down but it's a trade off. Weight versus control I'd take control personally. If you change the offset of your tires you might be a little better off but then you have the lip on the fiender to deal with. Tell me what you've done as far as the rear to keep it under control please.

The offset in the rear is as centered as it can get. The tires are centered right between the frame and fender lip. In 10 years of driving it way above the speed limit with 255/50's on GTA's, it never rubbed the fenders or frame.

The rear axle only had the control arms and the sway bar centering it before and that obviously isn't enough with the new PT swaybar.

 

[BlackMetal]

Cool picture you posted. Wouldn't it be beneficial to figure out a way to get those windows to stop popping out and creating drag? Not sure exactly what type of racing you're doing or if that really matters.

 

[xcessiv6]

Who's bar are you running

 

[IrvJr]

I have the ATR sway bar, UMI control arms and im running 17 x 9.5" rims with 275/40 tires. Nothing rubs now and i do like to take the corners fast. Nothing has rubbed yet, clearance is decent and the rear seems centered. Meaning the space from wheel to frame is equal on both sides.

 

[UNGN]

Who's bar are you running

The Spohn/SC&C/TR Parts bar with currie arms. It looks like watts link is the answer.

 

[UNGN]

Cool picture you posted. Wouldn't it be beneficial to figure out a way to get those windows to stop popping out and creating drag? Not sure exactly what type of racing you're doing or if that really matters.

We have them adjusted way in, too. Its funny, because I let off for a corner and the car will be loud and then get real quiet when the windows pop back in. They only pop out when going very fast.

The drag difference is very small between windows in or out and I had to back out of it to avoid going over 168 max tech speed during open road race events. With its current gearing, it will likely go close to 180.

I'll bet this happens to TTA's too, as the aerodynamics and windows are similar.

 

[scot w.]

First, I have to say that the handing with the pro touring bar is great. I was going into and coming out of corners 10 mph faster than with the Herb Adams bar I'd had in the car for 10 years, mostly because the suspension was absorbing the bumps instead of hopping over them.

but... after easily averaging 148 mph for 30 miles and backing off to cruise at 120 mph to get my average speed back to 135, the car started filling with smoke, coming from the back of the car.

It turns out that the Huge Herb Adams rear swaybar we had also helped triangulate the LCA's and locate the rear axle laterally... and the axle shifted 1.5" to the right, destroying the outside of one tire on the fender and melting the inside of the other tire against the frame. It looks like one of the adjustable uppers may have loosed up, but they were just tightened a month ago.

I'm beginning to think Adjustable uppers are pretty stupid on a car that is driven more than a 1/4 mile at a time and they are going to get pinned.

So it turns out, if you install the PT rear bar, unless you put in a panhard bad or a fayes2 watts link DON'T put in Spherical LCA/UCA joints and especially spherical adjustable uppers, unless you are running 215 wide tires.

Who'd have thought binding was good?

I ran the H & R bar when I auto-X'ed my old GN and never had Any issues with the rear shifting while in a turn.

I think it's weird for a Pro-Touring bar to shift like that and then have to buy something else to stop that too!!


Here is a pic of my car using the H & R bar! In this pic I was probably going 40-50 mph :biggrin:

 

[charlief1]

It's the Texas flying mile and he's done it before. As far as the rear moving around it's because of the stock bar keeping the rear more in line with the body because of the attachment location.. When you switched to the protouring bar it moves more and the rear moves more. If you add adjustable lowers you should be able to compensate to some degree. I had a simular issue with my old Skyhawk at high speed and you have to figure out which way it's moving then compensate by twisting the rear to one side slightly. I still think you'd be better off with a Watts link even though it's kind of a pain it will keep you more centered without the rubbing and you can move the rear side to side some without binding.

 

[UNGN]

I ran the H & R bar when I auto-X'ed my old GN and never had Any issues with the rear shifting while in a turn.

I think it's weird for a Pro-Touring bar to shift like that and then have to buy something else to stop that too!!


Here is a pic of my car using the H & R bar! In this pic I was probably going 40-50 mph :biggrin:

The difference might be I'm running spherical bushings and adjustable uppers. We have to tear it apart, still, but one of the uppers may have lengthened. If one upper lengthens with a regular bar, the rear axle will stay pretty centered.

I never noticed any rubbing pre-running the course and testing corners at over 100 mph (the speed limit is 75 mph on the road so its pretty easy to go 100 mph) and I didn't notice rubbing at 160 to 140 mph for 30 miles . It was when I slowed down that I noticed the problem.

 

[T-CHRGD]

First, I have to say that the handing with the pro touring bar is great. I was going into and coming out of corners 10 mph faster than with the Herb Adams bar I'd had in the car for 10 years, mostly because the suspension was absorbing the bumps instead of hopping over them.


So it turns out, if you install the PT rear bar, unless you put in a panhard bad or a fayes2 watts link DON'T put in Spherical LCA/UCA joints and especially spherical adjustable uppers, unless you are running 215 wide tires.

Yeah, now the axle can just slide side to side on the swaybar bushings

two words..................................Watts Link

 

[TR Custom Parts]

Running this same bar on my GN. I have the bushings mounted all the way towards the outsides of the bar. So far so good here. Not taking turns at 100mph though.

 

[scot w.]

The difference might be I'm running spherical bushings and adjustable uppers. We have to tear it apart, still, but one of the uppers may have lengthened. If one upper lengthens with a regular bar, the rear axle will stay pretty centered.

I never noticed any rubbing pre-running the course and testing corners at over 100 mph (the speed limit is 75 mph on the road so its pretty easy to go 100 mph) and I didn't notice rubbing at 160 to 140 mph for 30 miles . It was when I slowed down that I noticed the problem.

Still whether your running the adjustable uppers or the spherical bushings the bar should not be doing that! I'm around and Friends with allot of guys who have had there PRO-TOURING cars at SEMA and I run the same auto-cross with them here in TN every year and almost ALL of them have adjustable uppers and spherical bushings and there cars don't do that. Don't really know if ANY of them are even using the "Pro-touring bar".

The problem I have with this issue you posted is just, Why call it a "pro-touring" bar when it does this to your car? The problem I have is the "Pro-touring" crowd does auto-cross, road racing and drag racing and in order to achieve all three you certainly CAN NOT have the rear shifting on you!!

Onto the watts link set up, Wouldn't installing the watts link hold back from the function of the pro-touring bar or ANY bar for that matter? I think so.

I know the watts link bar works in what it's designed to do (keeping the rear centered).

I know that the H & R bar WORKS well for auto-Xing and I've had my GN up to 170MPH with it and NO issues at all !

Some items on the market today simply don't work even if they say "pro-touring" on it.. I personally would contact the manufacture and inform them of this issue and let them figure out what is wrong and how to remedy it.

My new project car a white 86' T-Type will be going the pro-touring route and I am planing on going a different route this time around. Seeing I personally know Brett from Air-Ride and Kyle & Stacy tucker from Detroit speed I will be using there knowledge and products on this new project.

Do a search on you tube for ( Run through the hills ) event held every year here in Pigeon forge. The event is a cruise through the mountains, Then a auto-X full day event, Then a Drag strip all day event. The winner MUST use the same tires in all events and trophy's along with tires that are sponsored.. We have recently branched out to having two events per year. The second event is held in Michigan in June of 09'. All star Performance/Lane Automotive has stepped up to sponsor a RTTHs type event in Michigan.
We will have Gingerman Raceway that Saturday and a huge parking lot to use for an auto-cross on Sunday.

Bottom line: A bar called the "pro-touring" bar should not do that regaurdless of adjustable uppers or spherical bushings.

Just my .02 worth