Darting front end, suicide straight axle

[zpi28]

I believe it has to do with the sidewall construction and tread flex. I used to run radials on my 64 Chevy and put the Pro Tracs on at the track. It drove like crap, had to drive it all the way down the track. In other words I was working the wheel the whole time to stay in my lane.

 

[donsrods]

21Willys, here are some things you might check. I would go back to square one and first of all, make sure your rear end is square to the centerline of the frame. Then make sure your front axle is square to the centerline and that the wheelbase on both sides is exactly the same.

That might sound obvious, but my Son's T bucket had some handling issues when we got it together. We found that in the haste of building it (88 days start to finish) we somehow got the wb off 9/16 of an inch on one side to the other. We also dialed in a little more caster and less toe in. It made a world of difference.

Air pressure is also very critical in hot rods with straight axles. I have found that 28 ish in the front and 24 ish in the back seems to work best on my cars with bias plies all around. If I go higher the tires bounce like a basket ball, and if I go less it doesn't track as straight.

Just a few things to keep you busy.

Don

 

[RPM]

The very first thing is the heim on the front of that drag link! It looks to be screwed just about all the way out and the nut is not tight. You may need a longer drag link. Fix the shock problem and get rid of the bias tires.

 

[Bamamav]

I'm surprised nobody has mentioned it, but I don't like the looks of those axle mounts. Looks a little weak to me, like they might be capable of flexing from side to side. Also looks like they're only welded on about 1/4 of the axle diameter. I'd think they would have been stronger if they went at least halfway around the axle, and some kind of gusset to keep them from flexing sideways.......

 

[21willys]

They are welded half way around and are 3/8" thick with gussets on the side. It's all professionally built and welded from a place in California. Plenty strong.

 

[21willys]

The very first thing is the heim on the front of that drag link! It looks to be screwed just about all the way out and the nut is not tight. You may need a longer drag link. Fix the shock problem and get rid of the bias tires.

I will take a look at the heim joint. It can turn a little but I dont think it can unthread it's self.



I'm going to have to wate til next weekend to mess with the car. I didn't get to it today and I'm leaving for work in a few hours again.

Thanks for the input.

 

[Bamamav]

They are welded half way around and are 3/8" thick with gussets on the side. It's all professionally built and welded from a place in California. Plenty strong.

OK, I guess it's the pic that makes it look that way, never saw the gussets. I guess I'll shut up now

 

[Torch]

push your car sideways until the sidewalls wobble...you'll see the difference between radials and bias ply.

the threads in the casing of a bias ply criss cross the tire from bead to bead...they are stiffer and have more internal friction thus the radials smooth ride and lower fuel consumption.

I like bias plies on manual steer trucks with large tires cuz they steer easier but with skinny tires there's not much difference

I had a 58 f350 I ran 8.75-16.5 bias ply farm treads on the rear and 9.50 16.5 highway tread on the front
awsome in the dirt and mud, not too howlie in the highway
sucked in the snow but that could have also been due to the wide front tires and the truck weighed 9,000 lbs had a 292 and a stick but didn't have a posie

 

[donsrods]

I'm like Torchmann, I really like bias plies a lot better on hot rods. I think they look better and can give a very good ride if the suspension is set up right. But I agree you don't want to mix bias and radial tires.

Don

 

[zzrodder]

Thanks for the replys guys!
I will check the toe in/out tomorrow morning and try as suggested.

Don I ran the car for a few real short trips without the shocks and they do make a difference. I am going to mount them different or switch to torsion shocks tho.
I will invest in the stabilizer shock. I was considering it anyways.

Ive heard people say to not use both bias and radials before but never heard the science behind it. Anybody know? Is it just the different flex rates?

Thanks again.

Radials and bias plys behave very differently and mixing them will make for a squirrely ride, though it's mostly evident while cornering. If you are not used to bias plys, they can feel twitchy as they tend to "tramline" or follow grooves, cracks or other irregularities in pavement - rain grooves or metal mesh bridge decks can be especially 'exciting'.

I started driving on old cars that only had bias plys, radials were an expensive new-fangled luxury - besides, the steering box on my first car was so loose I was always sawing the steering wheel back and forth so much I couldn't tell if it was the tires or not ...

 

[RPM]

On heims and clevis. They should be screwed in 1 1/2 times the diameter on the shank. So a 5/8" diameter heim should be screwed in 15/16" or 17 turns, plus the jam nut.

 

[STUBBS]

Ill chime in on this, all front ends are touchy in their own way, its like the difference between all your girlfriends, yeah that bad.. Some like 1/4 some 1/8 or 1/16" in, if they are toe out they will road walk and scrub in a bad way. and like previously mentioned before, mess with the caster angle also, this is where trial and error are key... Some like 3 to 5 degrees some cars like 9 and its also what you want it to feel like.. and honestly a bias ply on a front looks cool but for drivability I say radials, my buddies and I always run radials on fronts. You may consider a panhard bar, if your suspension starts doing the circle pattern up there it could be some of the issue, I know some guys who hammer on their cars upward of 120 mph to 170, they run panhard bars. Just some food for thought.

 

[donsrods]

Although I sound like a broken record on this, I can't stress enough how much of a positive difference a SoCal stabilizer will make on any straight axled car. I always dreaded the stretch of I-4 in Orlando when we went to Turkey Run, it has so many uneven sections and repairs it would toss my roadster all over the place when I drove up there. This year was totally different, my car handled the ruts and bad pavement so much better that I didn't feel like I was taking my life in my hands.

I also bought two for both of my Sons cars and they have both commented how much more secure they feel, even when they get on them hard or over bad road surfaces. It will be the best $40 or $80 (chrome version) you will ever spend. I already have one on my current rpu project and will never build another car without one.

Don

 

[billy]

Although I sound like a broken record on this, I can't stress enough how much of a positive difference a SoCal stabilizer will make on any straight axled car. I always dreaded the stretch of I-4 in Orlando when we went to Turkey Run, it has so many uneven sections and repairs it would toss my roadster all over the place when I drove up there. This year was totally different, my car handled the ruts and bad pavement so much better that I didn't feel like I was taking my life in my hands.

I also bought two for both of my Sons cars and they have both commented how much more secure they feel, even when they get on them hard or over bad road surfaces. It will be the best $40 or $80 (chrome version) you will ever spend. I already have one on my current rpu project and will never build another car without one.

Don

lose the bias plys and buy a stabilizer($5 at a junkyard)
it'll drive like a whole different car

 

[donsrods]

I can't offer any insight into how radials are vs bias as I only have ever run bias and probably only will run them forever. I have never understood why people dis bias plies as they can be just as roadworthy as radials, and they sure look a lot better on a fenderless car.

As I mentioned, I just put 500 miles on my 27 this past week, most of it on interstates, and my car drives right down the road one handed with no ill handling traits. I guess radials might be slightly better, but I will never know.

Don

 

[sgtpontiac]

Nothing wrong with Bias ply tires...

I can't offer any insight into how radials are vs bias as I only have ever run bias and probably only will run them forever. I have never understood why people dis bias plies as they can be just as roadworthy as radials, and they sure look a lot better on a fenderless car.

As I mentioned, I just put 500 miles on my 27 this past week, most of it on interstates, and my car drives right down the road one handed with no ill handling traits. I guess radials might be slightly better, but I will never know.

Don

Radials were designed for handling...keeping the tread surface flat to the road on turns...but unless you are planning some high speed road course driving, Bias ply tires are fine..... JMHO....

 

[STUBBS]

one tip on Bias plys.... Dont let em sit too long, they will flat spot and it takes about 20 min of driving before they round back out most of the time...

Not doing a "Dis" on bias ply tires, Ive had both and they are just as road worthy as radials...

I will agree a stabilizer does help for sure [

 

[billy]

i run bias plys on my antique jeep that is incapable of going over 45 mph.
and if they worked half as good as radials at modern speeds
they would be on my hotrod as well (they DO look great)
coker makes radials that look like old school tires
but i aint rich

 

[donsrods]

These are bias ply 16 inch Firestones. Watch the front tire, no movement at all and this stretch of road is not the smoothest.

http://www.youtube.com/watch?v=jQ-akqdncZU&feature=plcp

And these are also bias plies, but 15 inchers. Even at 92 mph they ran straight.

http://www.youtube.com/watch?v=CwVJRrX2vj4&feature=plcp

Don

 

[21willys]

I haven't had time to do anything with car yet. The only day I've took off was t day in the last few weeks. I'm busy trying to get everything ready for winter. Should be able to mess with it some Saturday as I am refusing to work lol.