From YouTube:
https://www.youtube.com/watch?v=HOmXCbVIU_c

Wowsers; is that spin I see on there acceptable and expected?

I wonder this fella spun at all; that car seems to really crush the tire at first, and the car really seemed to hop up.
https://www.youtube.com/watch?v=CqaF1QhUzwU

This message has been edited. Last edited by: Bad Nusz,

The speed of most of those cars: I would expect and want them dead hooked. The only time you shouldn't dead hook a car, is when it is prone to shake. And there was some shake in some of those shots.
The one guy hit the tire so hard he bounced. Not ideal. But not a disaster either.

Video appears to have been shot at a test and tune. Track prep is usually minimal. Only a few cars almost all with to much hit. No that much spin is not acceptable. Shocks to soft hits tire too hard then unloads and spins.

Thanks, guys. I have to wonder about that blue Mopar though. Does he need more air pressure? Or maybe he should tighten up the 'rebound' or extension of his shocks so the suspension doesn't push down on the tires so hard so quick?

That would kill the sidewalls of a tire pretty quickly, wouldn't it?

https://www.youtube.com/watch?v=s6SkdUkvDU8

The above video really seems to show the dynamics of leaf-spring rear suspension.

Does that car need more pinion angle?

Looks like that Dart in the second video could use some more air. That thing was crushing the tire.

Also BN, bear in mind that those Mopars really separate on the launch.

This message has been edited. Last edited by: CURTIS REED,

Looks like shocks are fully extended/topped out\ in video not enough air in tire for shure you can see spring slapping. maybe removing some timing might help? Been along time since Ive tuned leaf spring setup.

Traction bar car or pinion snubber? I had a Fast Mopar -pinion snubber and then 4 link. From what I see....0Might have too much pinion angle or it has the pinion snub is too close. I agree it needs a tighter shock too. You might want to leave a little lower too. Unless that kills your reaction time.

This message has been edited. Last edited by: BP758,

With the blue MOPAR in second video I would try more air in rear tires and stiffer shock settings. hitting tire too hard.

Geesh, you're not exaggerating! Imagine that tire when you take it off the rim, it'll fold up like an accordion, the size of a wallet!

Walker heavy Chevrolet Chevelle put on a clinic dragging a Ford Mustang A to B in this video, on a small DOT street tire. Pretty lap .

https://youtu.be/e-YtSHylNxE

Mike, I don't know why you deleted your comment about shocks. That blue car is a clinic about needing control.

quote:

Originally posted by CURTIS REED:
Mike, I don't know why you deleted your comment about shocks. That blue car is a clinic about needing control.

I deleted it because the topic is too subjective/opinionated. For all we know the Mopar/Dart may print tickets. The point I was making with the post I deleted was, a good set of dampers/shocks opens up another dimension. They allow a car to achieve objectives thought to be impossible.

The topic is just too subjective/opinion based. All you can do is show objectively on time slips, what you can do with a good set of dampers to articulate the dimension using evidence.

quote:

Originally posted by Mike Rietow:

quote:

Originally posted by CURTIS REED:
Mike, I don't know why you deleted your comment about shocks. That blue car is a clinic about needing control.

I deleted it because the topic is too subjective/opinionated. For all we know the Mopar/Dart may print tickets. The point I was making with the post I deleted was, a good set of dampers/shocks opens up another dimension. They allow a car to achieve objectives thought to be impossible.

The topic is just too subjective/opinion based. All you can do is show objectively on time slips, what you can do with a good set of dampers to articulate the dimension using evidence.

Based on what looked like a couple of beautiful launches with the Chevelle in your vids, it looks like your opinions certainly have merit.

I very much welcome all remarks if I ask a question on here, even if they appear to be opposed to each other.

It seems that many racers are right when they say that chassis setup and tuning is more of an art than a science.

I'm finally getting to a point where I 'think' I understand much about how leaf spring suspensions, traction controls and shocks work. To the point where I can or almost can explain it to a lay person. ;^) Thanks at least in part to you all.

Opinions always differ. I spoke to a very helpful man at Calvert Racing about CalTracs. He told me the prescribed method of pre-loading the devices, and to not listen to advice from those at the track or on the internet. Yet those other racers are claiming success with the differing methods they chose to set up their CalTracs.
I guess as always, YMMV.

Thanks all,
Troy

The best valving I've seen on over the counter economically priced shocks I know of is Strange double adjustable's.

Twenty years ago or so I was just like you, only the prevailing preconceived notion at the time was shocks don't matter. Big tires was what mattered.

Well I had this factory condition 69 Nova SS I didn't want to cut up to put big tires on it, so I got this wild idea shocks did matter with small tires. So I paid $1000 dollars for a set of Koni double adjustable shocks valved by Jerry Bickle, which was A LOT of money to spend at the time considering at that time, shocks didn't matter!

Anyway I'd suggest Strange for Caltracs or Jerry Bickle valved Koni's. Don't settle for junk. Get something Made in USA or western civilization.

I would suggest a set of these, in fact I could have a set shipped your way, but they're a little pricey.

I think to get ya going though, either of the two mentioned previously, would be a great investment.

I think you're on the right track either way though. The start is the hard part.

This was mine many, many years ago.

https://www.youtube.com/watch?v=sYQJVzRGdcc

Mike, how fast is the Nova? 60 foot, 660, etc.. weight, hp ?? Looks really nice!

quote:

Originally posted by stk 758 BP!:
Mike, how fast is the Nova? 60 foot, 660, etc.. weight, hp ?? Looks really nice!

It's a N/A 23 427 3.875 x 4.185 sbc with a set of out of the box Brodix T1 233 around 750 hp I'd imagine, 3200 lbs. It has dipped in the 5's N/A 1/8 mile 1.27 60ft. 2 sp powerglide 1.69 low x 4.88 gear. It's all 1/8 mile in Florida. It's basically a factory condition Nova with the front and back seat out, all steel roll up windows with a fiberglass hood and ladder bars, steel bumpers. In fact I just put the factory fuse box back to service to get all the horn, blinkers, tail, headlights etc etc back in play. We're getting it ready now for some Super Pro bracket racing dial'd around 6.40,I'm thinking 6.40 around 113 oughta be alright, changing the rear gear as I'm typing. Thanks bro I dig the 69 Camaro as well!

That’s cool! Thanks- We are a 427 +.070. .520 lift A/SA
9 inch tire, caltracs.. it’s been 1.29 10.0 car. Fun car. New motor this year so we’ll see. More tricks. And I don’t have a fast trans yet.. Griner 400..

quote:

Originally posted by stk 758 BP!:
That’s cool! Thanks- We are a 427 +.070. .520 lift A/SA
9 inch tire, caltracs.. it’s been 1.29 10.0 car. Fun car. New motor this year so we’ll see. More tricks. And I don’t have a fast trans yet.. Griner 400..

Wow 1.29, that's getting it done A/SA. I'd imagine you're speaking of a Proflite transmission. I can see that being really beneficial for ya A/SA. I actually entertained the idea on one myself, I located for some 1/4 mile. I'll get one eventually, when the right deal comes along. I'm looking myself. Good luck with the new power plant this year!