Burn out issues

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66Valiant528

66Valiant528

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How can I stop my car from fishtailing to the right every time I do my burnout? It has happened on every Mopar I have raced, which is 4, 68 Roadrunner, 71 Dart 360, 73 Duster 360 and now my Calvert Caltrac rear suspension 66 Valiant. Can't download videos.....sorry low tech....wtf. Line locks and front disc on all these cars.
 
You may find you rear axle is not square to the frame of the car.
Find the center point of the K frame.Run a tape measure from that point to the axle pad of each side of the rear to see if it is the same. If not you can shim the front leaf spring mount to compensate.
 
If the rear of the car is going right move the rear back on the left . if it is going left move it back on the right. I had the same problem with many mopars. What I found is the supports that the front spring hanger bolt to are installed in the body uneven. Make a shim shim plate with four holes and install it in front spring hanger. There were times I had to install longer studs/bolts. Up to 1/2 inch plates on some cars. My orange Duster took 3/8 plates

For a mini tubbed car you can move the pin hole on the spring perch. We made the one side of our rear perch a large oval hole with different inserts with the small hole at different locations. Many times you see crews holding cars straight when heating tires. Makes you laugh at times.
 
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When I spoke to an ex racer for "back in the day" with a 68 RR he said they had someone push on the right rear quarter, which they no longer allow, and his car did that too. I know the pass usually gets the extra leaf and due to the rotational forces the right rear squats first and probably drives the car to the right. And as pointed out this seems like a common thing. I like the idea of shimming the front spring hanger. I believe I have Mancini stiffening plates on the body but nothing between the hangers and the body.
As far as burn out procedures it's always been the same. Back up into water box, (on all 3 front street tire cars, blip the throttle to wet the tires, (except for street tires which get a dry burn out) step on brakes hard, engage line lock, 2nd gear burn out in 2 automatic trans cars, 2nd gear in stick car, high gear in Lenco shifted Valiant, Actually 3rd gear and then 4th as soon as they start spinning, per Lenco.
My Valiant, which is the only car I really care about as it is a race car only, will start to fishtail as well and pull me out of the groove. Car was launching straight but as I have increased launch rpms, now 5k, the car tends to go a bit to the right and then straight. Spinning my tires bunny hopping a few car lengths then straight down the quarter. Got a best 60 foot of 1.8 .and ran a 10.6 at 132....at LVD about 1000 ft above sea level this weekend. I have a few videos but they are too big to send. I realize the bunny hop is a shock setting issue. Viking DA all around. They suggested I try 9 and 9 in the rear, used to be 2 on compression and 9 on rebound. I'm sure that was the bunny hop.
Anyway I'd rely like to get the car to do a good burn out. Not getting enough heat in my 30x10.5x15 Hoosier drag tires.
Measuring and shimming sounds like a first step. Every Mopar I have run has done this. If I shim the left front hanger back a bit it won't make the car track funny? Or am I just fixing factory slop? Re aligment required afterwards? Thank you all.
 
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This is a 10.5 pass at 130. No wheelie . some tire spin in after launch and mid way through second but no hop. . The car was unpredictable before we shimmed the hanger. we ran the car through the full exhaust. After the new shop is done we will be playing with a car like yours similar to yours.



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66Valiant528 said:
As far as burn out procedures it's always been the same. Back up into water box, (on all 3 front street tire cars, blip the throttle to wet the tires, (except for street tires which get a dry burn out) step on brakes hard, engage line lock, 2nd gear burn out in 2 automatic trans cars
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With the torqueflite, which I assume you are using, try starting your burnout in 2nd gear and shift immediately to 3rd gear for the rest of the burnout. I used to burnout in 2nd gear but got a lot better results with shifting to 3rd. I also agree that you need to measure and see if your axle is not square to the frame.
 
Just out of curiosity, how much wheel speed are you generating on your burn out?
 
RockinRobin said:
With the torqueflite, which I assume you are using, try starting your burnout in 2nd gear and shift immediately to 3rd gear for the rest of the burnout. I used to burnout in 2nd gear but got a lot better results with shifting to 3rd. I also agree that you need to measure and see if your axle is not square to the frame.
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No more automatics at my house. A833 in my Roadrunner Lenco with a soft locker in my Valiant. Maybe try a 4th gear burn out in RR but it has street tires and I am not going to put tires on it. It is my street driver. Valiant is not street legal .
 
66Valiant528 said:
No more automatics at my house.
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Sorry, assumed automatic. Are you bracket racing? Index?
I bracket race and I understand wanting to be old school. I footbrake and launch at idle and I know it costs me races but I just don't want to do it any other way.
It sounds like you feel the same about manual transmission.
 
I have a 3 step and launch is tied into my clutch pedal. So far it's all been test and tune. Ya tried bracket at LVD this weekend and with only 1 qualifying round under my belt with 400 cars I dialed in at 10.36. Spun hard and ran a 2.1 60 and 11.5 at 132. Done....but as launch rpms have come up, working my nerves up to a 7200 rpm dump, car has gotten difficult to 60 and inconsistent. Was ok at 4200. But still, gotta fix my burn out. Can't get the slicks hot enough to grip on launch. 1 thing at a time.
 
In my humble opinion (my Cortina used a lenco with its former owner) with a lenco you NEED a spool. In a strip only car, why a soft locker?
My Tina was originally run with a small block/Lenco, and a spool with 14x32W tires.
How much tire are you using?
And I agree, step one is making sure the rearend is square in the car. Second, there are threads here and FBBO on tuning caltracs. Shock tuning is something else to explore, different settings on each side, maybe? You need tnt time.
With a 1.8 best with a ten second car, you have a long ways to go...... 1.8 is a slow twelve second car 60 ft.
 
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66Valiant528 said:
I have a 3 step and launch is tied into my clutch pedal. So far it's all been test and tune. Ya tried bracket at LVD this weekend and with only 1 qualifying round under my belt with 400 cars I dialed in at 10.36. Spun hard and ran a 2.1 60 and 11.5 at 132. Done....but as launch rpms have come up, working my nerves up to a 7200 rpm dump, car has gotten difficult to 60 and inconsistent. Was ok at 4200. But still, gotta fix my burn out. Can't get the slicks hot enough to grip on launch. 1 thing at a time.
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I run a 727 but it's the same principal, get the tries spinning and the car in high gear and roll out of the box. When I get in high gear, I spin it up to about 4500 or so and roll out of the box, then just ease out of the throttle.

Dart at the strip - YouTube
 
Read what OldManMopar posted about 6 times. I would also think that "weak spring flex" can cause this, think about how springs work. They arch and change length if they are not strong enough under extreme power. When they twist under power they change length. The old 70RR 440-6 had the "trak pak" It had I think 2 extra "half leaves" under the front of the right rear spring to stiffen up that part of the spring.
 
33IMP said:
In my humble opinion (my Cortina used a lenco with its former owner) with a lenco you NEED a spool. In a strip only car, why a soft locker?
My Tina was originally run with a small block/Lenco, and a spool with 14x32W tires.
How much tire are you using?
And I agree, step one is making sure the rearend is square in the car. Second, there are threads here and FBBO on tuning caltracs. Shock tuning is something else to explore, different settings on each side, maybe? You need tnt time.
With a 1.8 best with a ten second car, you have a long ways to go...... 1.8 is a slow twelve second car 60 ft.
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I have a spool in my Strange super 60. Soft locker is because a stick car hits the tires hard. A soft locker let's you leave then engages fully, that's the theory anyway. My best 60 is 1.6. 1.8 was my best this weekend past. Sorry about the confusion.
 
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67Dart273 said:
Read what OldManMopar posted about 6 times. I would also think that "weak spring flex" can cause this, think about how springs work. They arch and change length if they are not strong enough under extreme power. When they twist under power they change length. The old 70RR 440-6 had the "trak pak" It had I think 2 extra "half leaves" under the front of the right rear spring to stiffen up that part of the spring.
Click to expand...
I have the Calvert racing split mono-leafs and there bar set up.
 
Different rear weights can cause it. If the car launches straight and hooks, maybe leave it be, but lower the left front torsion bar a turn and see if it stops.
 
furrystump said:
Different rear weights can cause it. If the car launches straight and hooks, maybe leave it be, but lower the left front torsion bar a turn and see if it stops.
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Very interesting. First measure. Too bad the tracks are so far away. 90 miles to New England Dragway 131 miles to Lebanon Valley Dragway. I'll get the car squared away. I know it'll take time.
 
I was at LVD this past weekend too. Track prep was not great, my one and only time trial my Dart, which has a Jerico with a Soft-Loc clutch cut a 1.625 60 ft. and it ran 11.0 at 123.5 that is a bad 60 ft. for my Dart. The Jerico has a 3.04 first 2.0 second 1.38 third 1.0 fourth and 4.30 in the Dana, 9x28 M/T, Cal-Trac rear suspension( with the Cal-Trac bars adjusted by my son with me in the driver's seat the car never kicks sideways on the burn out, when I first put the Cal-Trac's on and I adjusted them with nobody in the car it would always slide to the right). First round I took one round of clutch out for a softer hit (thought it was going to be a time trial) dialed in and 11 flat. Dart went a 1.502 60 ft. 6.867 1/8, by this time I had about 3 car lengths on the car I gave a .47 second head start to, I let off at the 1000 ft. and and let him come up alongside. Just before the stripe I hit the brakes hard, he hit his harder, I went a 10.978 at 107.2 on a 11.0 dial, he did a 11.535 at 104.5 on a 11.47 dial, I went home, but still had a good day.
66Valiant528 what is your first gear ratio, with those 60 ft. times, it sounds like not enough first gear and to much clutch and you are bogging the engine, or you are spinning the tires real bad.
 
Okay, I get it now (late, I know!). I thought you meant a soft locker in the rear. You mean a soft lock CLUTCH! Okay, my bad.
The rest of what I said, I still think is right.....
 
furrystump, talk about bad track prep, you guys in the Fast class looked like you were racing on a gravel road. Did any of you get any traction?
 
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