Ron Pope Motorsports                California Custom Roadsters               

Wondering problem

BOB S

Supporting Member
Supporting Member
For years I've had a problem with the car moving around under power, and then when I let off the throttle it wanders back the other direction. I have looked and looked and cannot seem to put my finger on the problem!
 
For years I've had a problem with the car moving around under power, and then when I let off the throttle it wanders back the other direction. I have looked and looked and cannot seem to put my finger on the problem!
I had an old aluminum Corvair steering box with the steering wheel straight up and down, I thought that was the problem. I replaced the steering box in front of the firewall and put the steering wheel on a tilt under the dashboard .that didn't do anything to help
 
If you have a locker unit in the rear end it will do that.
I actually pulled out a open third member thinking it might help to have both titers working and replaced it with the Detroit locker same problem .
This is really strange to me
my race car is on 4 link and it leaves the starting line straight as an arrow and also has the Detroit locker .
the way my T. bucket moves around is absolutely ridiculous and uncontrollable
thanks for your reply
 
A friend of mine had this problem with his T and it was so severe it was bad scarey to drive. it ended up being a poorly engineered rear panard bar. I changed the mounting points of that and it drove fine .
 
It sounds like you have rear steer. Make sure all the suspension attachments are tight and configured correctly.
 
If your T has an auto trans, have someone watch the rear axle for movement, when you hold the brakes and drop it in drive and then reverse. If you can block the front wheels and not use the brakes, the results may be more noticeable. If one end has some travel it will act like rear steer.
 
My ''t'' pulled bad to the right when you got on it.Let up on the gas it would pull to the left. I thought it was because I have solid motor mounts & cross steering . Then I put a front panhard bar on it ,took care of that problem .Drives so much nicer..........
 
My ''t'' pulled bad to the right when you got on it.Let up on the gas it would pull to the left. I thought it was because I have solid motor mounts & cross steering . Then I put a front panhard bar on it ,took care of that problem .Drives so much nicer..........

Thank you for your input but I do not have a cross steer system on my T.
with all of the comments from everybody and helpful hints I have finally figured out the problem. I went down to a friend shop that does smog testing here in California he had an old set of rollers that you put your wheels on so you can spin the tires. I had to put new bearings in the rotating shaft but I got it working perfectly! I put my T. up on the rollers strapped it down and had a friend of mine get into the car and play with the throttle, while I watched the rear suspension. When he pushed down on the throttle and got into the blower I watched the panhard bar flex to my surprise it was actually bending under the torque. I'm in the process of building a thicker and more stable panhard bar . I am also going to redo the mounting points on the frame and housing I'm going to make everything much thicker and stronger.
I'm absolutely sure this will solve my problem and it will be an absolute enjoyment to drive the car without fighting for pulling left and right
 
Glad your on the path to fixing your problem
 
Let us know if this solves the problem. I sort of think there is something else going on here, but in this case, MY mileage may vary.
 
Thank you for your input but I do not have a cross steer system on my T.
with all of the comments from everybody and helpful hints I have finally figured out the problem. I went down to a friend shop that does smog testing here in California he had an old set of rollers that you put your wheels on so you can spin the tires. I had to put new bearings in the rotating shaft but I got it working perfectly! I put my T. up on the rollers strapped it down and had a friend of mine get into the car and play with the throttle, while I watched the rear suspension. When he pushed down on the throttle and got into the blower I watched the panhard bar flex to my surprise it was actually bending under the torque. I'm in the process of building a thicker and more stable panhard bar . I am also going to redo the mounting points on the frame and housing I'm going to make everything much thicker and stronger.
I'm absolutely sure this will solve my problem and it will be an absolute enjoyment to drive the car without fighting for pulling left and right


Bob,

I was about to ask how much power and what kind of suspension front and rear you have. My initial thinking was torque steer. These cars are usually usually not very stiff in the torsional axis front to rear. Anytime you apply power and it moves to the right then comes back left after power is let off tells me it is torque steer. If you have a conventional mounted leaf spring or even coil overs on the front or reared then I feel a centering devise of some type is mandatory. If you have radius rods or hairpins on the reared then you have in effect a big anti roll bar system. As the power level goes up the right rear wants to rotate down and the left side rotates up causing the front of your radius rod to go up. That causes the car to steer right. Since you have a 4 link race car you probably have an anti roll bar in the rear of that car. It to will try to drive the right rear down but you use the anti roll bar to resist this. The difference being a race car had either a tube structured chassis with a lot of vertical and diagonal tubing or a roll bar.cage that resist that chassis deflection. A t-bucket is usually just out of luck in that arena as there is usually very little structure above those 2x3" frame rails. As for your panard bar. Diameter is always better to increase strength versus wall thickness. Wall thickness helps to but diameter increase helps a lot more. Both working together will get you there too. Maybe if you described all of your suspension we could get a better picture of what is going on. Hope this will give you something to think about. Good luck with you car.

George
 
As FluidFloyd said, this seems to be a isssue when big horse #s/torque#s are being thrown out. When a blown motor is thrown into the mix, alot of flexing can follow. Guys have to remember, alot of times when a blower is involved in the case of the 350s and the 6-71's, power can be increased by as much as 50-55%....
Torque rods, frames have been know to flex and mounts get cracked, bent....
Its very easy to get a 300-350 horse 350, add a BDS blower kit, and hit 550 horses. Its also very easy to get 500 horses and bunch-o-torque with normally aspirated 454's, 455's, and 440's with todays performance parts.
Folks need to plan accordingly. It doesn't take long for a long thin walled tube that was adequate with a mild sbc to became inadequate with more power.
 

     Ron Pope Motorsports                Advertise with Us!     
Back
Top