TA radials have been around forever, and popular, but they really are junk. They don't do anything better than a middle of the pack all season touring tire, no matter what they look like. Even a goodyear eagle gt is much better at everything, except maybe wear. The TAs are just not in the realm of a real performance tire.

Some of the best radials are not going to come in a 235-60, but I would look around anyway. Going to a 225-60 will open up many more options, and the smaller size will not lose any performance because you can get a tire that is so much better. Any off the better high performance or Ultra high performance radials that are still all season would make a night and day difference. Look for the better Yokohamas, Bridgestones, Nittos, Michelin or even Coopers. Just about any of them will be much better.

I used to really like the yokohama A008s. That model has been replaced but I have seen cars run easy 12.5s on them in the 225-60-15 size. Not pretend 12.5s, real, at the track, right off the street 12.5s. I never timed it at the track, but I was running very close to the same with 225-60 Bridgestone RE950s a few years ago with a 34?? lb car. That was a solid 11 second car with Hoosier DOT Quicktimes.

The BFG drag radials in the same size you are running will be all that you would ever need, however. I would just get a set of wheels and swap them. They are still ok to drive on, just not all the time. I don't think you have enough power to get too concerned with the suspension, just get some good tires.

Go shopping again!!!

Be careful... most of the Mopar SS springs I have seen are way to stiff for "Street / Strip" type cars, especially SL6 powered ones.

Here is how I set-up rear leaf springs for light A-Body SL6 Drag cars:

I start with the most sagged-out pair of light weight leaf springs, usually the ones with 4 1/2 leafs in the pile.
Take them apart and add 2 or 3 leafs, I cut the leafs so the front of the stack is thick and stiff with a nice "staircase" and use 2 tight clamps. the cut leafs I add do not extend rearward much beond the U-bolt clamping point. I sometimes grind the cut end of the new upper leafs in the stack, to help reduce the gap they create.

The rear of the pile remains soft with only 3 long leafs and 1 or 2 short ones at the bottom. The gaol is to have the spring pile dead flat when installed and at rest with normal weight in the car. No clamps are used on the rear segment of the spring pile.

I use longer rear shackles (hangers) usually the ones off a B or E body Mopar. The rear hangers must be angled reward, I try to get 45 degrees of reward angle.

Up front, drill 2 additional holes in the front spring mount bracket so the front spring eye's position can be raised or lowered. With proper lay-out, these new holes can help get you the 45 degrees of rear hanger angle.
The shocks used are the softest factory shocks I can find and I add a pinion snubber with a 1 to 1 1/2 inch clearance gap to the hard stop.

Here is how it works:
Hit the throttle hard and the car's front end lifts, sending weigh rearward.
The rearend "rotates" and the stiff front section of the leaf pile positively locates the rear end housing and transfers the axle's counter-rotation forces to the rear of the leaf spring pile, which spread open and arches.
The pinion snubber "hits" and that accents the body raising and the spreading / arching of the rear spring section.
The spring arching pulls the rear hangers forward, this action increases the distance between the rear spring eyes and the chassis, the hangers lift the chassis, acting as a wedge, using all the rearward moving vehicle weight to push the rearend / tires into the pavement.

The keys to making all this work:
Soft spring rates and shocks that allow weight to move rearward.
A flat leaf spring that will arch with rearend housing counter-rotation.
Rear spring hangers (shackles) that are angled reward at rest and do not go past straight down when "energized" during spring arching.
DD

I am Certainly no Suspension Expert here, but my car is a stick - and I have always just dumped the clutch - I am going to try a softer launch technique this season, but anyway I just run my old tired stock six cylinder 5 leaf springs that my car rolled out of the factory with - I was thinking about super stocks for a while, but romeo Said that the doesn't need em - it just doesn't make that much power.

I run dot drag slicks - M/H brand but my car will hook up aggressively with street tires too. I run anywhere between 15-21 PSI depending on temps and track conditions. I also run a Mopar Perf. adjustable pinion snubber with air shocks set at 60PSI. It works for me.

Greg

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http://www.youtube.com/hyperpack

Good info...
Basically, the Mopar rear suspension system is well engineered and set-up, right off the production line. The addition of a pinion snubber is about all that is needed when using it on the drag strip.

If an owner starts changing things, you can loose the geometry the factory gave us. The most common change I see, that causes problems, too much arch in the leaf springs followed closely by to much added stiffness. (usually the 2 are related)
DD

in other words I use the kiss method.....


keep it simple stupid..


Greg

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http://www.youtube.com/hyperpack

Keep It Super Simple...
DD

Doc,

Sorry for the error in my post about the SS springs. I meant to list the 2800 lb. springs instead of the 3000 lb. ones. They give my son's '68 Dart a good ride while keeping the car sitting level and it hooks good to.

Rich

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'67 Dart w/ 225 for my daughter
'68 Dart 270 w/ 225 for my son
'69 Dart GT for me

I would agree that the stock suspension is good stuff especially for the slant. One thing I plan on adding, or would've if I had a little more money would be trac-bars. We had some on the Challenger which my memory doesn't go back far enough to remember. The cheap clamps we tore out of a mach 1 were simply 2in tube welded to the springs (?) they were cheap and looked like trash.
So to sum it all up stock is good. Than I would add a simply snubber. I would heavily suggest the trac bars to run with street tire there maybe $300 from summit. Four links are last on my list, which are the best but also the most expensive.
Cheater slicks suck in the wet, like wash your car and take a blow dryer to them before you drive suck.

All cars need to have a certain amount of 'hit' on the tire. High horsepower cars do most of it with power. Slant sixes need to do it with a soft suspension.
The Mopar SS springs aren't too stiff spring rate wise, 120lb/in auto, 160lb/in stick, they are too stiff on the rear segment. They are meant for a higher powered V8. The softer, or easier the rear segment will give, the more hit on the tire. The SS springs are just a compromise, they will get someone with a V8 in the ball park. Even they can be improved on for each car but most racers bolt them on and go.
Too much hit can be as bad as not enough, so don't go overboard.
Some of the ways to make more hit Doc covered, longer shackles angled rearward. Fewer clamps on the rear segment, or moving the clamps forward, will give more hit, opposite to lessen. Along with the half leaves that help preload the right side, the rear clamps can be staggered to help the car launch more evenly. One thing about SS springs, the rear segment is 1" longer which makes the segment easier to bend and also helps angle the shackle rearward so it is free to move forward as the spring bends. As far as the front segment, just make it stiff.
The idea a snubber will launch a car is debatable. I feel it is only a safety device to keep the rear housing from rotating too far and breaking the U-joint. There are many fast 9&10 second leaf springs cars that do not run a snubber, they have enough pinion down angle and a stiff enough front segment not to need one. If you run the stock pinion angle and a soft rear segment spring, run a snubber to help keep the shaft in it.
High spring rate SS spring were last used in '67. I have a set that came on my '67 Bel II that are 300 lb/in, my 'D100 has a softer spring on it!

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Slant Cecil

In scanning the thread, I haven't seen much talk about the front suspension. For good hook-up at the strip, your *front* shocks could be hurting you a lot worse than the rear ones. Drag race front shocks should be extremely assymetric- in other words they should provide a normal amount of resistance to being compressed (front end moving downard) but almost zero resistance to the front end rising to maximize weight transfer. An old cheapskate trick is to put a pair of very worn-out shocks on the front. Also, disconnecting the sway bar can help because it takes the stiffness of its bushings out of the picture. You want the front end to rise freely, and then let the rear suspension geometry actively use the engine's torque to RAISE the rear end. Big beefy T-bars also hurt straight-line hook-up, and serious big-block drag racers will go and find slant-six T-bars for their cars. To me, that's a bit too much of a compromise because I like to turn corners also. But the general theory is true- for best drag performance you want the front end very, very compliant, not stiff.


A well-set-up Mopar will literally jump off the starting line- the whole car will rise upward slightly- the front because of weight transfer and the rear because the pinion snubber and front halves of the leaf springs are forcing it upward as the torque rotates the axle nose-up (and at the same time jamming the rear tires into the ground). At the most extreme, the nose should rise and the rear stay about level. Under no circumstances do you want the rear end to visibly drop more than a fraction of an inch

With regard to BFG Radial T/As- there is a break in the T/A lineup between 60-series and lower profiles and the higher-profile (70 series and up) tires. The 60-series tires are much better compound. I would call them far more than a "middle of the pack" all-season tire, and I ues them on my daily driver and love them. But they're still definitely an all-season, general-purpose street tire and won't do you any favors at the track. To get good grip, you're going to need to sacrifice some longevity and either the M/T or BFG drag radials are just the ticket. Very streetable, but not 40,000 mile life for sure.

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Well lite suspension work is not enough. Before working on my hesition the tires would break free and now I 've worked out about half of the hesition, its gotten ridculous. I am even fish tailing now. Imagine if I get the hesition total fixed. I 've decided to buy a spare set of steel wheels and some BFG Drag Radials 235-60-15. Maybe I'll get a 1.99 60', that'll be cool.

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67Cuda,FAST EZEFI,340cu,CR=10.25,RollerCam&Rocker (XR268HR,#20-810-9)(#1622-16)(EddyRPM#60779,#7576), (MSD6AL,#6425) A904, GearVendorsOD, 8 1/4,3.55:1, ClassicAir