# Traction bars?



## Mike Honcho (10 mo ago)

68 Firebird 400 which is now putting out a respectable amount of HP. 4 speed and has Posi. When I was at lower power and I slipped the clutch a bit to get some wheel spin (just for fun, don't do burnouts) I noticed the back end tends to drift left. Figured it was just me and my driving. Now the tires are easy to break loose in 1st and 2nd. But it definitely drifts left and I have to ease off the throttle to regain traction and maintain control. Have not tried turning into the drift cause I don't want to end up on Youtube.

Will traction bars help and even if they do is there another underlying situation that also needs to be addressed. Going to get front end aligned and any recommendations on how to tighten up the handling is appreciated. Been a 5 year journey to get performance right and now its fun stuff like this and some cosmetic pieces I'm changing out on the interior. And finally burning some gas!


----------



## PontiacJim (Dec 29, 2012)

Mike Honcho said:


> 68 Firebird 400 which is now putting out a respectable amount of HP. 4 speed and has Posi. When I was at lower power and I slipped the clutch a bit to get some wheel spin (just for fun, don't do burnouts) I noticed the back end tends to drift left. Figured it was just me and my driving. Now the tires are easy to break loose in 1st and 2nd. But it definitely drifts left and I have to ease off the throttle to regain traction and maintain control. Have not tried turning into the drift cause I don't want to end up on Youtube.
> 
> Will traction bars help and even if they do is there another underlying situation that also needs to be addressed. Going to get front end aligned and any recommendations on how to tighten up the handling is appreciated. Been a 5 year journey to get performance right and now its fun stuff like this and some cosmetic pieces I'm changing out on the interior. And finally burning some gas!



If an original Firebird 400,it has factory traction bars. It will also have additional floor plating - I believe where the front subframe bolts to the floor pan to add strength to the non-framed car. Sub-frame connectors were always popular as an add-on to both the Camaro and Firebird when racing or adding more HP.

Assuming your posi is working and stock ride height, this would be my opinion.

Typically, with posi, my experience is that the rear will kick to the right when losing traction - smoking tires. Should not be that excessive that you go sideways - but with enough HP, you can, I've had that experience. But normally, as the car moves forward it'll straighten or you only need a little steering correction. Burning out and making a hard left or right, as in from a stop sign or light, can definitely throw the car sideways and is also the easiest way to get the tires smoking because you are shifting the weight of the car to one side when you make that burnout/turn. You can find yourself spinning around or in an uncontrolled spin that if not caught quickly can result in a situation you can't get out of and the body shop gets a little of your business. LOL

Depending on the age, you may have a weak, or both, leaf spring and need to replace them. The leafs also have bushings in the "eyes" and they can wear and need to be replaced. If you have the factory traction bars, check them - assume some bushing on them as well.

Check your rear brakes. You could have a brake shoe hanging up or slightly dragging causing just enough drag to make one side "hold" while the other side has no resistance and the dragging shoe could cause the car to take a left or right point instead of going straight.

In any case, address the rear suspension first and make sure no weak leaf springs or worn/soft bushings. New tires could be an option - if tires were somehow at different heights, either worn or incorrect/unmatched tire pressure, this could have an affect on launch. Add-on traction bars would be a last resort if you don't have the factory bars. Different types of devices and some will hang below the leaf spring and you will lose some road clearance. They do work, but they can also hinder handling if they don't articulate and cause the suspension to bind, as they are designed for the most part for straight line acceleration and operation.


----------



## lust4speed (Jul 5, 2019)

It might be worthwhile to rule out that the crown of the road is causing the drift. At a safe time position the car on the opposite side of the road and launch. If the rear still drifts to the right then you can rule out the road causing the problem.

Another thing I would try is to swap rear tires side to side and see if that changes anything. Also it could be as said above that the spring rates are allowing one tire to push more than the other drifting the back out.

My son's '68 Firebird was running low 11.20's at 123 and would launch straight at the track pulling the front wheels slightly off the ground. Burnouts at the track were arrow straight. On the street the car was more of a handful that it should have been - it might go straight, or right or left depending on surface irregularities. When it did dart to the side it did it quickly, and this was with Mickey Thompson drag radials. Rear suspension was modified with Cal-Tracs and the addition of a half spring on the passenger side similar to the old Dodge Ramcharger setup, and it did have the sub-frame connectors welded in. 

Pontiac Heaven drags years ago:


----------



## Mike Honcho (10 mo ago)

PontiacJim, the posi is new as are the leaf springs. I'm on the road till next Wednesday and I'll look for factory traction bars when I get back. Tire pressure is 25 PSI both sides per the door sticker although the tire can go up to 40 PSI. I will check on brakes, bushings, and eyes. This is great info and a place to start.

Lust4speed, I am now on very flat roads back in Florida. I'll find a nice newer truly flat parking lot and try there since even a flat road has some crown. When I drove the car in Cape Cod the road had a steep crown and it drifted left uphill. But that could also be because I'm a crappy driver and still getting used to this beast. And nice picture.

Thanks for info and I'll report back if I find any improvements.


----------



## PontiacJim (Dec 29, 2012)

Mike Honcho said:


> PontiacJim, the posi is new as are the leaf springs. I'm on the road till next Wednesday and I'll look for factory traction bars when I get back. Tire pressure is 25 PSI both sides per the door sticker although the tire can go up to 40 PSI. I will check on brakes, bushings, and eyes. This is great info and a place to start.
> 
> Lust4speed, I am now on very flat roads back in Florida. I'll find a nice newer truly flat parking lot and try there since even a flat road has some crown. When I drove the car in Cape Cod the road had a steep crown and it drifted left uphill. But that could also be because I'm a crappy driver and still getting used to this beast. And nice picture.
> 
> Thanks for info and I'll report back if I find any improvements.



Hmmmm. 25 PSI per the door sticker. You running bias ply tires????????

Pump the tires up to 40 PSI if your tires are rated for 40 PSI. Most tires are 32 PSI but some of the newer are indeed 40 PSI. That might be your problem right there.


----------



## Mike Honcho (10 mo ago)

Jim, thank you. This is why I am here. To learn what I am unaware of. I can help anyone here with marine diesel problems. Many years experience with that. But on these cool old cars I am quite the beginner. I will put the tires at 40 PSI to start and see what the difference is. Never occurred to me that pressure was based on tires available back then.


----------



## armyadarkness (Dec 7, 2020)

Mike Honcho said:


> PontiacJim, the posi is new as are the leaf springs. I'm on the road till next Wednesday and I'll look for factory traction bars when I get back. Tire pressure is 25 PSI both sides per the door sticker although the tire can go up to 40 PSI. I will check on brakes, bushings, and eyes. This is great info and a place to start.
> 
> Lust4speed, I am now on very flat roads back in Florida. I'll find a nice newer truly flat parking lot and try there since even a flat road has some crown. When I drove the car in Cape Cod the road had a steep crown and it drifted left uphill. But that could also be because I'm a crappy driver and still getting used to this beast. And nice picture.
> 
> Thanks for info and I'll report back if I find any improvements.


My car goes to the left real bad when the posi breaks loose. It's absolutely normal. When you have both back wheels spinning then there is nothing to hold the car on its course. Traction bars aren't going to prevent this while they're going to do is help you get traction slightly quicker. Regardless, if you burn the tires you're going to go sideways. In one of my videos you can actually see my car doing it at speed in third gear. You need to embrace it


----------



## Mike Honcho (10 mo ago)

Some pix.


----------



## Baaad65 (Aug 29, 2019)

WOW ! That's sweet, I would have a Firebird as my second car, love the dash and vinyl top and chrome nose👍 What's under the hood?


----------



## Mike Honcho (10 mo ago)

Red on Red 68 400, 4 speed Muncie M-21, 48 casting heads (ported), Hooker Headers, X pipe exhaust, Comp cam, Holley 650 double pumper, Edlebrock Performer intake, Posi 3:55, Hurst shifter, front discs 

From my Signature on Firebirdnation.com


----------



## Baaad65 (Aug 29, 2019)

That works for me 👍


----------



## stuinnh_9505 (Oct 29, 2021)

What tire pressure is everyone running in new -er 14 inch tires? I have been running 26 lbs


----------



## PontiacJim (Dec 29, 2012)

stuinnh_9505 said:


> What tire pressure is everyone running in new -er 14 inch tires? I have been running 26 lbs


My preference on the tires I run is 32 PSI which can be found on the sidewall. Some newer tire types run 40 PSI. I run 32 on my Hyundai and when they get to around I believe 26PSI, I have a dash light that indicates a lower air pressure. Helpful if a tire is going flat - you can catch it. The car will feel a little "mushy" going into tight corners, so I do notice the lower pressure. I have run them lower, out of laziness, and they still work, but again, the car does not feel as stable when the tires are at 32.

You can also get better wear and mileage, but the beat way to check wear would be to visually look and/or use a tread depth gauge which can be bought. I drive a tractor-trailer and I only pull empty trailers for pick-up or delivery from customers to our repair shop. If I put in the air pressure stated on the sidewall, around 95-105PSI, it over inflates the tires and creates a crown effect of the tread. The tires are designed to haul heavy loads, so the heavy loads pushed down on that crown and the tread wears evenly. Without the heavy weight of a loaded trailer, my tires will wear out down the middle of the tread which is the top most area of the crown. So in order for my tires to war evenly, I only put 80PSI in the tires. I get an even wear on the tread and longer life out of them, along with a softer ride as the tires can flex a little more and act as a shock absorber of sorts. 105PSI makes those truck tires like rocks and with little to no weight on the tires, it is like riding with no suspension and it beats me to death. I hate my truck because it rides so horrible without weight or simply "bobtailing" with no trailer.


----------



## Mike Honcho (10 mo ago)

So have been driving a bit and while maybe I posted this on another thread already going back to the beginning of this one well, "Houston, we have a problem". Something is loose in the rear. I can feel a wiggle in the rear stomping on it on the highway. Also whenever I take off making a right turn there is a wiggle and tire chirp even taking off easy. Something is amiss. Going to gently cruise and enjoy the car and it goes back to my trusted mechanic up north in March. Maybe earlier since I have a 2 week project near Boston and if the weather window looks good may take it up in February.

Once there frame connectors, tranny gone through, clutch, etc. Anything they recommend so we can be finished. Gonna do rear disc upgrade just to make my guy go through everything underneath. Amazing how when glaring issues are corrected you finally notice things that otherwise were not noticeable. 

Did I mention these old Pontiacs are super cool?


----------



## armyadarkness (Dec 7, 2020)

There have been many threads, where an owner attempts to fix an issue, using a side-bar method or cheat, but it only winds up creating another issue.

The weak link will always be exploited... however, they never mention that you might have ten weak links. Every time you fix one, you'll find the next!


----------



## PontiacJim (Dec 29, 2012)

Mike Honcho said:


> So have been driving a bit and while maybe I posted this on another thread already going back to the beginning of this one well, "Houston, we have a problem". Something is loose in the rear. I can feel a wiggle in the rear stomping on it on the highway. Also whenever I take off making a right turn there is a wiggle and tire chirp even taking off easy. Something is amiss. Going to gently cruise and enjoy the car and it goes back to my trusted mechanic up north in March. Maybe earlier since I have a 2 week project near Boston and if the weather window looks good may take it up in February.
> 
> Once there frame connectors, tranny gone through, clutch, etc. Anything they recommend so we can be finished. Gonna do rear disc upgrade just to make my guy go through everything underneath. Amazing how when glaring issues are corrected you finally notice things that otherwise were not noticeable.
> 
> Did I mention these old Pontiacs are super cool?


Since you said it has new leaf springs, I have to assume new/correct eyelet bushings and matching bolts. It is possible that either the U-bolt (s) that hold the spring to the rear axle have loosened up or if new, may have not been the correct length and the nuts bottomed out on the threads before they could tighten the springs to the axle and because thy tightened up, the owner may have assumed they were good to go when they were not.

Next thought is that the springs have a center pin in the middle that holds all the leaves together (if multi-leaves) or simply as a single leaf, and this pin has to go into the hole in the bracket on the rear axle to align/center the axle correctly on the springs. Being aftermarket, it is possible that an incorrect pin "head" was not used or could even be too narrow and not fit tight in the axle bracket hole allowing the axle to shift around.

Or, could be a mixture of both issues. So I would be making sure the bushings were good and correct diameter bolts were used so they are tight, check your U-bolts for tightness and make sure some did not realize the threaded area was too short and the bolts did not tighten up on the u-bolts, and then check the pin that goes into the axle bracket that holds the axle centered and in position on the springs.

Finally, inspect the hanger perches front and rear for cracks, breaks, or rust through. The frame rails are not real hefty like a car frame and I have seen them rot out from the inside.

Keep us posted.


----------



## Mike Honcho (10 mo ago)

Jim, one of the best things about this car is zero rust. I overpaid but then again I didn’t. Car is going up on the lift and we are going through everything front to back.


----------

