Hooked pulling front wheels then spun

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Walker434

Walker434

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Took the Dart to Bowling Green on Saturday and ran 10.65 @ 128. The car launched hard, pulled the front wheels almost a foot off the ground then lost traction.

I have SS springs, CR 9 way adjustable shocks in the back. Cheap 90/10s up front. The Back shocks are set on 7. Should I adjust them to be firmer at the track? Like 8 or 9?

I saw several other cars having this problem too. I hope it was the track because I'm getting ready to leave for drag week and need to run low 10s. Spinning is no bueno.

Dart 34.jpg


Dart 37.jpg
 
Being as they're not double adjustable, I would try #8 and runs couple times to see if it helps.. do you have a video? That may help people's ideas as well.
 
my car was doing this and I found a softer setting worked best like 2 on the dr side and 3 on the ps . I was told that to high of a setting will unload the tire , it seems to work better .
 
Horseshoe49 said:
You may be running out of shock travel and topping the shock out as well.
Click to expand...
This sounds probable, and would be my best guess.

Your MPH in the 1/8 and 1/4 look almost identical to my car...you should be in the 6.5's 1/8 and 10.3's in the 1/4. Good luck at drag week!
 
Do you have the rear of the leafs strapped or not strapped ? And as said, if the shocks bottom out fully extended it will unload the tires.
B&E body shocks are longer if I remember correctly.
 
The shocks are long enough I have checked, not bottoming out. I have an extra clamp on the front segment of the spring and I've removed the back segment. I'll try a softer setting on my shocks. Hopefully it works, I can't afford to spin at drag week.
 
You want the shock to extend faster and compress harder, sounds like the set up should work fine, I had Monroe racing shocks on the rear of my car back in the day and they were extra long 75/25. I could carry the front wheels almost all the way through 1st gear.
 
I've run 1.39 to 1.43 sixty foot times with half ton truck shocks, just cheap hydraulic shocks. There two inches longer than the car shocks. But don't tell anyone the haters will come out. :)
 
Bottoming out and topping out are 2 different animals, not trying to split hairs just making sure we are talking the same lingo. Make sure your shock has enough outward extension is what I was referring to.
 
Both shock travel and spring rate need to compliment suspension travel. In the front suspension, that means the front springs/bars should reach their unloaded point at the same time as the front suspension tops out. If the front springs/bars are still pre-loaded when they reach their limit of travel, you will see an abrupt transition in tire load at the rear as the front tires lift off the ground, which in-turn can cause the rear to break traction. Basically that means a spring/bar can be too soft for the available travel when the car is capable of pulling the front tires.

Grant
 
brian6pac said:
You want the shock to extend faster and compress harder, sounds like the set up should work fine, I had Monroe racing shocks on the rear of my car back in the day and they were extra long 75/25. I could carry the front wheels almost all the way through 1st gear.
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The first time I had this car to a track with this combo a couple weeks ago..(Different Track 1/8 Mile) it hooked and carried the front wheels through first gear and did a 1.47 60ft time. I'm really hoping this track was just poorly prepped and I don't have to change too much. I'm going to try setting the rear shocks on 5 and see if this helps. Might call Calvert tomorrow and pick their brain also. Thanks for the help FABO.
 
This might be a dumb question but did you bleed the shocks before you put them on ?
I also found this chart I thought I had one but couldn't find it,
The Calvert's are 1 is firmest and 9 is softest, seems backwards to me.
 

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brian6pac said:
This might be a dumb question but did you bleed the shocks before you put them on ?
I also found this chart I thought I had one but couldn't find it,
The Calvert's are 1 is firmest and 9 is softest, seems backwards to me.
Click to expand...
9 is firm 1 is soft. the reference point would be straight up for selection.
 
brian6pac said:
This might be a dumb question but did you bleed the shocks before you put them on ?
I also found this chart I thought I had one but couldn't find it,
The Calvert's are 1 is firmest and 9 is softest, seems backwards to me.
Click to expand...

Which direction does the shock get "softer" or "firmer"? Or does going to a different number make the bump stiffer and rebound softer? Or the other way around?

I'm dealing with a customer with a set of these. And no one can answer that question.
 
yellow rose said:
Which direction does the shock get "softer" or "firmer"? Or does going to a different number make the bump stiffer and rebound softer? Or the other way around?

I'm dealing with a customer with a set of these. And no one can answer that question.
Click to expand...

I agree, That's why I was looking for the instruction. I was going to buy a set at one time but never did. I just went to the website and got the instructions, It is confusing #1 is firmer, #9 is softer ? in both directions or in one direction.
 
brian6pac said:
I agree, That's why I was looking for the instruction. I was going to buy a set at one time but never did. I just went to the website and got the instructions, It is confusing #1 is firmer, #9 is softer ? in both directions or in one direction.
Click to expand...


That's what I can't figure out. Calvert tries to explain it to me but it doesn't make sense.

I've told them I want be stiffer in bump and not change the extension. I'm on number 5. Which way do I go?? They never give me the correct answer.

So I've told my customer to sell them and spend the money on some DA Viking shocks so they can be tuned.
 
To adjust Calvert 9 ways, you need to turn the dial counter clockwise and center between 1 and 9.
then turn clockwise to the preferred number setting.
All the adjustable shocks are set pretty much the same way.
 
I'd try slowing the front end down a little if it's hitting and unloading.

More air in the tire if the tire is deforming on the hit too.
 
fishmens67 said:
To adjust Calvert 9 ways, you need to turn the dial counter clockwise and center between 1 and 9.
then turn clockwise to the preferred number setting.
All the adjustable shocks are set pretty much the same way.
Click to expand...

Still doesn't say compression or rebound
 
I was thinking tire pressure also to low, How much pressure are you running ?
 
The correct terminology is rebound and dampening. I would think a high end shock would have settings for both.

Setting up suspension for dirtbikes is quite an art. Not one I can say I have mastered unfortunately. The correlation between the settings and effect are often counterintuitive.
For example....if you feel your forks are harsh instinct tells you to soften the compression. But you actually need to increase or stiffen the compression. What is happening is your forks are being compressed more and more with each bump and getting further and further into the spring compression...
It also might be due to incorrect rear shock settings or undersized springs !
 
Yea, You don't get it. If the forks are compressing more and more you have to soften up the rebound, if your washing out in the corners you need to soften up the rebound because the tire is not hitting the ground fast enough to get traction. The compression is just that you don't want it bouncing the bike up in the air just the tire. If it throws the bike up than the fastest rebound wont get the tire back on the ground.

And it's compression and rebound, dampening is related to both.
 
brian6pac said:
Yea, You don't get it. If the forks are compressing more and more you have to soften up the rebound, if your washing out in the corners you need to soften up the rebound because the tire is not hitting the ground fast enough to get traction. The compression is just that you don't want it bouncing the bike up in the air just the tire. If it throws the bike up than the fastest rebound wont get the tire back on the ground.



And it's compression and rebound, dampening is related to both.
Click to expand...

I stand corrected on the use of the term dampening ....
But increasing the compression rate will help in fast bumps. Not saying you are wrong in certain instances .... thus the ART.
Bikes have far more variables than a drag car.
The point is that the correction for a symptom may be the opposite of your initial thoughts.
 
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