Wheel spin issues

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1967formulaS

1967formulaS

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Hi guys,
I've got a 67 formula S fastback
It's got a mild 440, hemi 18 spline 4 speed, strange dana s60 with 4.3 gears, 28 10.5 r15 tyres on rear (bf Goodrich), I have the front raised up just short of the droop stops.
I'm just getting ready to set this thing up and wanted to hear from guys that are either racing or have raced with similar setups.
I still have the original formula s torsion bars and rear leaf springs still in the car. ( it is an original 383/4 speed car)

Even with 1/4 throttle, she is spinning off the line.

I have a set of MH racemasters semi slicks on the way as I want to still be able to drive on the street.

Would SS springs, 6 cylinder torsion bars and an adjustable pinion snubber get me sorted or should I go down the ladder bar or slapper bar route?

I don't want to be doing massive wheel stands. I just want out of the hole nice and flat and quick so I can destroy some rice burners. :)
 
90/10 shocks on the front - adjustable or not, your choice. The "smaller" torsion bars are a point of debate - but they will aid in launch because they are a lighter rate and will allow the front to rise a tad quicker. Hell yea on the adjustable snubber, hell no on the slapper bars. SS springs wouldn't hurt for sure - they are popular for a reason. There is a thing with the stock leaf springs - I think it is loosening the front half by removing the spring clamps.. do some research, there is a great read online about this - I really should have bookmarked it because this comes up all the time. Google it - eventually you'll find it - or just wait it out on here, I assure you someone will chime in and set you up with the www. or a recent thread link. Very nice car BTW, like the look a lot.
 
ScampMike said:
90/10 shocks on the front - adjustable or not, your choice. The "smaller" torsion bars are a point of debate - but they will aid in launch because they are a lighter rate and will allow the front to rise a tad quicker. Hell yea on the adjustable snubber, hell no on the slapper bars. SS springs wouldn't hurt for sure - they are popular for a reason. There is a thing with the stock leaf springs - I think it is loosening the front half by removing the spring clamps.. do some research, there is a great read online about this - I really should have bookmarked it because this comes up all the time. Google it - eventually you'll find it - or just wait it out on here, I assure you someone will chime in and set you up with the www. or a recent thread link. Very nice car BTW, like the look a lot.
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wrong on loosening the front clamps !
 
Yes, it's best if you have a clamp on each spring of the front segment. You'll have to experiment with removing the rear clamps, and properly fitted slapper bars work excellent for traction control & limiting spring wrap. I have them on my '68. I have them set-up so the front snubber is just barely touching the front spring eye of my 2 right side SS springs.

The car will nearly dead hook on the street from a stop when the Nitto Drag Radials are warm, and that's with nearly 500 hp, a 3000 rpm stall converter, 2.76 to 1 first gear ratio and 3.91's. Without the slapper bars, it just ahnilates the tires.
 
everything I have ever read or heard about traction bars on a leaf spring set up on a Mopar has been negative.. something about hurting the rear if you have too much HP and the rear isn't braced... also CAUSES wrap up.. makes me wonder what you've got going on that is different.. enlighten us please (not being a smart *** here, I am truly curious)
jbc426 said:
Yes, it's best if you have a clamp on each spring of the front segment. You'll have to experiment with removing the rear clamps, and properly fitted slapper bars work excellent for traction control & limiting spring wrap. I have them on my '68. I have them set-up so the front snubber is just barely touching the front spring eye of my 2 right side SS springs.

The car will nearly dead hook on the street from a stop when the Nitto Drag Radials are warm, and that's with nearly 500 hp, a 3000 rpm stall converter, 2.76 to 1 first gear ratio and 3.91's. Without the slapper bars, it just ahnilates the tires.
Click to expand...
 
Like I was telling my buddy a few weekends ago after I got his new motor's timing, carb and transmission kickdown all dialed in and running way better than it was before all the basics were set up properly, they're called speed secrets for a reason. Not everyone knows them.

I can count on one hand the number of cars with properly set-up slapper bars out of the hundreds cars I have seen in my life that had them bolted on. You are right, they will wrap the front spring segment if the snubber is placed in back of the front spring eyelet. Also, they won't do anything for you if the snubber is too far away from touching the spring eyelet.

Most slapper bars do not fit right straight out of the box. They typically have to have the rear mounting perch cut, adjusted and rewelded to properly place the snubber (of which you should cut about 1/3 of it off) directly over and just barely touching the front spring eye right where the front bolt attaches through the leaf spring.

Once properly adjusted, make sure to use quality hardware to attach it firmly to the spring, retorque them a few times and check them regularly.

When properly set-up, the work exceptionally well on the semi-elliptical rear leaf design of Mopars.
 
well I'll be dipped - sounds like solid (and obviously proven) auto-science, I like it. Thanks for sharing your secret!
 
jbc426 said:
Yes, it's best if you have a clamp on each spring of the front segment. You'll have to experiment with removing the rear clamps, and properly fitted slapper bars work excellent for traction control & limiting spring wrap. I have them on my '68. I have them set-up so the front snubber is just barely touching the front spring eye of my 2 right side SS springs.

The car will nearly dead hook on the street from a stop when the Nitto Drag Radials are warm, and that's with nearly 500 hp, a 3000 rpm stall converter, 2.76 to 1 first gear ratio and 3.91's. Without the slapper bars, it just ahnilates the tires.
Click to expand...

thanx for the post, my car was setup just like this in the late 70's, it worked.
I don't share feedback on the net to avoid the naysayers.
 
jbc426 said:
Like I was telling my buddy a few weekends ago after I got his new motor's timing, carb and transmission kickdown all dialed in and running way better than it was before all the basics were set up properly, they're called speed secrets for a reason. Not everyone knows them.

I can count on one hand the number of cars with properly set-up slapper bars out of the hundreds cars I have seen in my life that had them bolted on. You are right, they will wrap the front spring segment if the snubber is placed in back of the front spring eyelet. Also, they won't do anything for you if the snubber is too far away from touching the spring eyelet.

Most slapper bars do not fit right straight out of the box. They typically have to have the rear mounting perch cut, adjusted and rewelded to properly place the snubber (of which you should cut about 1/3 of it off) directly over and just barely touching the front spring eye right where the front bolt attaches through the leaf spring.

Once properly adjusted, make sure to use quality hardware to attach it firmly to the spring, retorque them a few times and check them regularly.

When properly set-up, the work exceptionally well on the semi-elliptical rear leaf design of Mopars.
Click to expand...

yes x2
 
4 speed at the track needs a bias type slick tire. Drag radials or street type tires you will have wheel spin, unless you ease it off the line.
 
You are on the right track with the super stock springs, snubber , six cyl bars, and 90/10 shocks. It definitely takes a little more work to get a 4 spd car to hook. The best thing I did to mine was an aluminum flywheel. It takes some of the hit out of it off the line and will rev a little quicker. But definitely get the other things on there first.
 
Yes, the 4 speed car could probably benefit from a pinion snubber. You will also likely need to reinforce the factory snubber plate on the under side of the body with 1/4" plate to keep it from pounding the factory plate through the floor.
 
Excellent feedback guys, thankyou.
We have a set of corner weights on loan from a friend, so I'll get it setup on there and see our weight distribution, corner weights, overall weight etc and figure out the centre of gravity on the car. If anything, this will be interesting and handy for any future plans.
I'll start gathering the essentials and make plans to fabricate our own bars.
Will post a few pics of her on the scales.
We done My mates blown hemi mainline ute yesterday. I was surprised at the weight distribution.
 

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jbc426 said:
Like I was telling my buddy a few weekends ago after I got his new motor's timing, carb and transmission kickdown all dialed in and running way better than it was before all the basics were set up properly, they're called speed secrets for a reason. Not everyone knows them.

I can count on one hand the number of cars with properly set-up slapper bars out of the hundreds cars I have seen in my life that had them bolted on. You are right, they will wrap the front spring segment if the snubber is placed in back of the front spring eyelet. Also, they won't do anything for you if the snubber is too far away from touching the spring eyelet.

Most slapper bars do not fit right straight out of the box. They typically have to have the rear mounting perch cut, adjusted and rewelded to properly place the snubber (of which you should cut about 1/3 of it off) directly over and just barely touching the front spring eye right where the front bolt attaches through the leaf spring.

Once properly adjusted, make sure to use quality hardware to attach it firmly to the spring, retorque them a few times and check them regularly.

When properly set-up, the work exceptionally well on the semi-elliptical rear leaf design of Mopars.
Click to expand...

Agree like the others. Mine work pretty darn good. 4 spd car.
 
Just spitballing here, but maybe a set of tires and rims for the street and a set of tires for drag racing? It just seems unrealistic to be safe on the street and hook on the track.
I've noticed a half second difference between dragstrips. All in 60ft times. One no prep, and the other you could loose a shoe walking across the starting line.
 
I am running Drag Radials and it drives great on the street rain or shine and hooks pretty good at the track.
 

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SS Spring! They Work!

Traction bars, in time, will Bend your Leaf Springs. Will make a "S" out of the from segment of your springs.

Start by clamping that front segment on both sides. If you are capable of building Slapper Bars, you can figure out how to clamp the front segment with some metal and a couple of bolts with nylon nuts.

Try it! you will Like it!:D
 
These guys are right. You will need some different tires. BFG anything sucks for traction.
 
..as in cranking up on the torsion bars? Agreed. The car needs to settle back down after launch and be drive-able. The Gasser look is cool, but not functional for racing an A-Body Mopar. However you do want the nose to rise up some on launch - weight transfer.. just wondering if you misinterpreted what was said earlier or if you're throwing out a statement - as in an FYI...?
crackedback said:
Raising the front end is going the wrong direction.
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