PP Torsion rear causing car to kick out sideway to right?

[Sean709]

Hey guys im new to these cars but have drag raced for 20 years and running across a issue where with traction control off rolling into it in 3rd around 60 mph when the car breaks loose it always kicks the rear end to the right. I check tire pressures and my car has adjustable sway bar end links and I mset and check they have no pre load. Car feels like it doesnt have posi. So I started searching around and saw a video from American muscle on the torsion center section saying it is not for drag racing and doesnt lock up equal well for drag racing. I even had my alignment checked with rear toe etc. I have been mid 7s @ 185 and 1.19 60 ft and never had to get out of it like this car is making me do.

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[Coyote Chase]

Wow... That's impressive!
My Ecoboost does that when I do my burn out in the water box. But never when I launch or shift gears. I don't know if it's because I don't have your power or that I get good grip due to tires and running on treated tracks??

 

[jwt]

If you want to rule the Torsen in or out as the issue you could always change the diff fluid for a higher viscosity, that changes the toque bias. test it an see, then go for lower with maybe a friction modifier (AFAIK Ford allows that, but check first) and try again. If there is a change in the handling or speed it occurs then you know the Torsen is the issue, if no change then maybe your back to more mundane worn or soft bushings etc

Theoretically a Torsen offers perfect toque split at all times but as the tires, suspension and chassis flex anything could be happening as the Torsen moves torque from left to right. So altering the torque bias might let you diagnose quickly as above

 

[Sean709]

Wow... That's impressive!
My Ecoboost does that when I do my burn out in the water box. But never when I launch or shift gears. I don't know if it's because I don't have your power or that I get good grip due to tires and running on treated tracks??

Yes it's also cold out and not on a track but I have had drag cars for decades actually had a whippled terminator with almost 700 whp and used to take it out in very cold temps and do probably 1/8 mile long blazers on the highway and it was straight as a arrow. Something is off.

 

[Sean709]

If you want to rule the Torsen in or out as the issue you could always change the diff fluid for a higher viscosity, that changes the toque bias. test it an see, then go for lower with maybe a friction modifier (AFAIK Ford allows that, but check first) and try again. If there is a change in the handling or speed it occurs then you know the Torsen is the issue, if no change then maybe your back to more mundane worn or soft bushings etc

Theoretically a Torsen offers perfect toque split at all times but as the tires, suspension and chassis flex anything could be happening as the Torsen moves torque from left to right. So altering the torque bias might let you diagnose quickly as above

Thanks for info I will try that with the thick 140

 

[Sean709]

This is with all traction controls off - connector by air box un plugged. Before I knew about the plug and even advanced trac off of course it was like training wheels and didnt do this.

 

[K4fxd]

If you haven't already I'd get the alignment checked.

I'd also look into getting poly bushings, the factory bushings are rubber band soft.

 

[Sean709]

If you haven't already I'd get the alignment checked.

I'd also look into getting poly bushings, the factory bushings are rubber band soft.

It does have the solid BMR bushings along with these other suspension mods on this list.

 

[Sean709]

It does have the solid BMR bushings along with these other suspension mods on this list.

This is the alignment just done after steeda coilover kit was installed. The front has to have alot of camber or it will have tire rub with the car so low and hub centric spacers. I am wonder about the rear tow in being a little different on each side. I'm not sure if it's enough to cause something like this. Thanks for any help as all the race / performance stuff I ever had was straight axle with a spool and much different.

 

[K4fxd]

This is a drag car?

I'd reduce the rear camber to something below 1 degree, 0 if possible.

I'm not sure about the rear tow either. I would like the thrust angle to be 0

Hopefully someone who knows more than me will chime in.

 

[Sean709]

This is a drag car?

I'd reduce the rear camber to something below 1 degree, 0 if possible.

I'm not sure about the rear tow either. I would like the thrust angle to be 0

Hopefully someone who knows more than me will chime in.

It is not a straight up drag car. I drive it only on the street but more of a straight launch type style and will but putting drag radials on it. The original owner did most of the road course type mods on it like the sway bars etc.

 

[K4fxd]

I've got a road race set up on mine, mostly steeda parts.My alignment is .10 toe in each side on the rear for a total of .20, thrust angle 0

When on the drag strip and I get rubber an gear changes my car goes straight.

I've got the clutch type LSD.

Ive got a real good alignment shop and I tell them a number they give it to me. It took over 3 hours for the last alignment but it is nuts even side to side.

After the test drive they bring it back on the rack to make sure the settings stayed put.

 

[Keeffa]

Hey guys im new to these cars but have drag raced for 20 years and running across a issue where with traction control off rolling into it in 3rd around 60 mph when the car breaks loose it always kicks the rear end to the right. I check tire pressures and my car has adjustable sway bar end links and I mset and check they have no pre load. Car feels like it doesnt have posi. So I started searching around and saw a video from American muscle on the torsion center section saying it is not for drag racing and doesnt lock up equal well for drag racing. I even had my alignment checked with rear toe etc. I have been mid 7s @ 185 and 1.19 60 ft and never had to get out of it like this car is making me do.

Checkout Steeda for all there stop the hop parts for the IRS and LCA bearing. makes a big difference.

 

[Sean709]

This is a drag car?

I'd reduce the rear camber to something below 1 degree, 0 if possible.

I'm not sure about the rear tow either. I would like the thrust angle to be 0

Hopefully someone who knows more than me will chime in.

I agree 100 percent on the rear camber being to much for straight line traction. I brought it to get aligned after front struts and camber plates and knew we needed alot of front camber and didnt really want to mess with the rear camber and never mentioned touching it but the shop I guess thought to adjust the same as front for handling I found out when picking it up. Gonna bring it to somewhere and dial that back a bit along with getting rear toe the same and may have them put a touch more front toe for a total of around .1 Total so it isnt darting around as much. Does anybody know what these cars have around for rear toe and camber from the factory.

 

[Sean709]

I've got a road race set up on mine, mostly steeda parts.My alignment is .10 toe in each side on the rear for a total of .20, thrust angle 0

When on the drag strip and I get rubber an gear changes my car goes straight.

I've got the clutch type LSD.

Ive got a real good alignment shop and I tell them a number they give it to me. It took over 3 hours for the last alignment but it is nuts even side to side.

After the test drive they bring it back on the rack to make sure the settings stayed put.

Sweet. Around here in CT near me there isnt any shops that good. Most are tire shops with help that probably get to work by walking to it. No clue and I dont even trust them to mount a tire.

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