Stock suspension drag racers step in please.

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Kevin D.

Kevin D.

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I have a 69 dart that I use as a street/strip car.Trying to keep it as close to stock looking as possible.Well finally got my 416 in and running.Went to track hoping the prepped track would help.No such luck it just blows the 225/60-15 M/t drag radials off.The car has 4.88 gears which worked well with my hot 340 but not here.90-10 shocks up front.Heavy duty rear springs.Springs have the off set kit installed.4200 converter.Left in 2nd gear 1 pass and went 7.30 with a 1.58 60 ft. That's thru mufflers in full street trim.Frame is tied.I could go to 275/60 or slicks.But really what I am asking is your opinion on what needs to be done to get car to hook up without butchering it up.Thanks Kevin.
 
Less gear, 3.23-3.91. Slant six front bars will help transfer the weight too. Stick some blown out shocks up front or take em off.
 
Less gear and a taller tire. Drag radials don't like tracks that aren't well prepped, so you my want to consider a bias ply tire. Also, the stroker won't need anywhere near as much gear as the 340 did.

For what it's worth, my stroker is backed up by 4.10 gears and 28" x 11.5" Hoosier Quick Time Pro tires. No traction issues at all, street/strip, mid 10's.
 
Remember to try one change at a time.I would start with some slicks for traction,from there I would add adjustable rear shocks(never mentioned what you have in the rear now).You might need to swap your HD leafs to either SS springs or Caltracs with mono leaf setup.It all depends on how much track time you,ll be seeing.You need to get a base time trial to move forward with changes.JMO
 
Air pressure in tires?
Travel in front end and ease of movement
Springs clamped
Pinion Angle
Changing launch rpm

There's so much that can be done.

Joe's Duster has a stroker, 4500 verter, 4.10, ss springs and 275/60/15 drag radials with nothing fancy and runs mid 1.4's for 60's.

Video of the car leaving from side and rear can help a lot in figuring things out.
 
4.88 gears now have 90/10 shock up front. 50/50 in rear.Slant 6 torsion bars.Launch at 1500 rpm.Battery in trunk.
 
You need more tire. I would go with the 275/60 Drag Radial or a slick.
 
don't remove the front shocks. drag shocks, but don't run with out them. Super Stock springs are old school but can still work well with the right tire. what is the car doing in the lights, is the rpm where you want it? 4.88 gear is steep with a limited tire.
 
That's a pretty good 60ft time for leaf springs. But one other suggestion: Adjustable Pinion snubber set contacting floor or 1/2 in from floor when on ground.
 
i'm set up real close to what you have.

71 dart, 408, powerglide, 4.86 gear, 5,000 stall, 29.5x9 M/T slicks. I have adjustable QA1 shocks on all 4 corners of the car, slant 6 torsion bars, and super stock springs that have every leaf in front of the axle clamped. the rear clamps are still on behind the axle just as they came. I leave at 3,000 rpm on a trans brake. car picks the front tires up about 6-8 inches and sixty foots 1.45-1.49 with a powerglide.

as mentioned already you may have a little too much gear. you are running the same gear as me basically, but you have a 2.40 something 1st gear ratio in your tranny vs a 1.76 in mine.

I would start out like this.

clamp the front of your current leaf springs, and unclamp the rear since you are foot braking and not letting go of a trans brake or dumping a clutch.

go with a taller slick to kill some gear, and give you a bigger contact patch
get the front end working!!!!! this may be the most important.

get at least 5-8 degrees of pinion angle. this is very important. if you need more then go to an Advance Auto Parts store and look where they have their helper springs, spring clamps, and such. they will have packs of pinion angle shims in that section that come in 2 degrees and are MUCH cheaper than ordering from somewhere.

try to get at least 5 inches of travel in the front end before the tire leaves the ground. leaving the factory strut rods and going to one with solid bushings and heim joints will help maybe as much as anything. trim the upper control arm bump stop down to gain more travel, or take it off all together as long as the side of the shock doesn't hit anything after you do.

I could only get 4 inches of travel out of mine, but more is desirable.

one more trick that will make the car hook and run fast is to add 100-200 pounds of weight in the trunk as far back as possible. just use something like a ballast box and make sure it is secure. I have seen many guys do this and pick up on ET even though they weigh more. if a light car won't hook, then being lighter isn't doing you any good.

try that first and I think you will be surprised. the areas of concern after doing those things would be if the rear end and body are seperating too quickly at launch and shocking the tire. in that case the 50-50 shocks would have to make way for an adjustable so that you could slow down the seperation and let the tire plant properly without being hit too hard.

the pinion snubber could also be used at this time before going to super stock springs. 1/2 inch from the floor is usually a good place. I have one on my car but it doesn't even touch the floor with the springs clamped up. I have it set at 1 1/2 inches just in case a clamp or something breaks. at least it will save my u joints from failure.

good luck and let us know how it turns out.
 
The friends are racing a 71 Dart with over 1000Hp, on 275 drag radials and Caltracs. They have to control the engine to keep the tires applied.
Using as tall tire as will fit, will get ya the most footprint, but ya knew that?!
 
Unless it's a 1/8th mile drag car only you probably don't need anywhere near the gear you have now. I've seen a lot of real fast 1/4 mile stroker combinations running 3.91 and 4.10 gears with 28" tall tires. I have a real mild 408 in my Cuda and it's a long shot from a drag car but still runs real low 12's on cheap Nitto drag radials with a 3.55 gear. I think taller gears and taller tires will not only make your car much more streetable but hook much better. 340's love those short gears but strokers are a complete different ball game.
 
Hoosier Quick Time Pro's hook well.. Stock rear springs. Front of spring clamped. 451 stroker Auto 4.10's. As said before strokers don't need steep gears.Are they preping the track well?
 

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71gtdart said:
i'm set up real close to what you have.

71 dart, 408, powerglide, 4.86 gear, 5,000 stall, 29.5x9 M/T slicks. I have adjustable QA1 shocks on all 4 corners of the car, slant 6 torsion bars, and super stock springs that have every leaf in front of the axle clamped. the rear clamps are still on behind the axle just as they came. I leave at 3,000 rpm on a trans brake. car picks the front tires up about 6-8 inches and sixty foots 1.45-1.49 with a powerglide.

as mentioned already you may have a little too much gear. you are running the same gear as me basically, but you have a 2.40 something 1st gear ratio in your tranny vs a 1.76 in mine.

I would start out like this.

clamp the front of your current leaf springs, and unclamp the rear since you are foot braking and not letting go of a trans brake or dumping a clutch.

go with a taller slick to kill some gear, and give you a bigger contact patch
get the front end working!!!!! this may be the most important.

get at least 5-8 degrees of pinion angle. this is very important. if you need more then go to an Advance Auto Parts store and look where they have their helper springs, spring clamps, and such. they will have packs of pinion angle shims in that section that come in 2 degrees and are MUCH cheaper than ordering from somewhere.

try to get at least 5 inches of travel in the front end before the tire leaves the ground. leaving the factory strut rods and going to one with solid bushings and heim joints will help maybe as much as anything. trim the upper control arm bump stop down to gain more travel, or take it off all together as long as the side of the shock doesn't hit anything after you do.

I could only get 4 inches of travel out of mine, but more is desirable.

one more trick that will make the car hook and run fast is to add 100-200 pounds of weight in the trunk as far back as possible. just use something like a ballast box and make sure it is secure. I have seen many guys do this and pick up on ET even though they weigh more. if a light car won't hook, then being lighter isn't doing you any good.

try that first and I think you will be surprised. the areas of concern after doing those things would be if the rear end and body are seperating too quickly at launch and shocking the tire. in that case the 50-50 shocks would have to make way for an adjustable so that you could slow down the seperation and let the tire plant properly without being hit too hard.

the pinion snubber could also be used at this time before going to super stock springs. 1/2 inch from the floor is usually a good place. I have one on my car but it doesn't even touch the floor with the springs clamped up. I have it set at 1 1/2 inches just in case a clamp or something breaks. at least it will save my u joints from failure.

good luck and let us know how it turns out.
Click to expand...


I to am worried that going from my 340 with 456 gears, to a 408 stroker is going to give me grate fits with planting the tire!!!!!
I liked this enough that i printed it out and will put it on my wind shield for now:burnout:

You wouldn't have some pic's or better description for the SS Spring front segment clamp, set up?
 
Cudafever said:
I to am worried that going from my 340 with 456 gears, to a 408 stroker is going to give me grate fits with planting the tire!!!!!
I liked this enough that i printed it out and will put it on my wind shield for now:burnout:

You wouldn't have some pic's or better description for the SS Spring front segment clamp, set up?
Click to expand...
images






this isn't my car but here you go.

the only thing you do is clamp at the end of each leaf in front of the axle.
the only difference in mine from the photo is that I didn't clamp the short leaf that he is pointing at. in my opinion that leaf is so short it can not distort. now, maybe I am missing the boat, and should have done that leaf. you can try it both ways.

also, I put a clamp right up against the factory clamp where he did not.

http://shop.advanceautoparts.com/p/autocraft-leaf-spring-clamp-kit-1-set-ac131401-13-140/10053472-P

these are the clamps that I use. you can get them from advance auto parts. they make 2 1/2'' and 3'' clamps. you want the 2 1/2''. you can see that the shoulder on the clamp is long after the threads stop. what I done was took a tap and run it over the shoulders so that I would not run out of thread before the clamp got tight. I also marked the clamps and cut off the excess threads after I tightend them up. works like a charm.
 
Thanks for taking the time. Going to have to invest in some of them!
 
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