REDGAR

I have 12 way single adjustable (both rebound and compression at the same time) QA1 shocks on all four corners. I run the fronts between 4 and 2 (loosest) and the car seems to be bouncing. I run the backs from the 8-6. I have seen short times with the current slicks from 1.399 one time to 1.42 ish regular and in the video below 1.45ish. Car seems to leave then bounce and bounce again and then one more time.

So I am hitting Atco Friday or Sunday and am desperate. going to set the fronts to 12 (tightest) and see what happens.

Do you think this is crazy or worth a shot?

The shocks are about 4 years old and I am sending them out to be rebuilt after this weekend as I am sure they are in need of it.

Any help or analysis appreciated.

www.challengevideos.com/shock_hop.wmv

chrismorales75

Looks to me like it just spun the tires and dropped the front back down, plus the car is squatting in the rear.

I wouldn't think you'd run it at 4 in the front then change it to 12, why not try a click or two at a time.

If you send the shocks to have them rebuilt have them valve your front shocks to "R" type fixed compression valving.

When you run the front shocks at 1/2/3/4 there is not much resistance stopping them from coming back down, it's basically 10/10 20/20/ 30/30 40/40 valving which obviously isn't much compared to 90/10 80/20 70/30 rates.

The more you tighten it up the slower the front reacts, which isn't going to help your car unless it had some wheel standing issues.

NJSPDER

iTrader: (2)

the shocks definately need to be freshened as we discussed in memphis. firming up the fronts will help a little bit, but it appears the issue is with the rears.
watching the videos several times through i started to notice that the bouncing in the front follows the rear not staying planted. basically the car sits back really nice at the launch but then there isn't enough rear shock to hold it down. as the rear rises the front starts to drop, then the springs just bounce the car back and forth.

tektrans

iTrader: (23)

I would bet setting the fronts at "12" will just result in wheelspin.
Set the fronts at "0". Getting the car to transfer the weight back there better with the looser front setting may plant those rears harder and let you carry the fronts out longer.
The car is squatting but I don't think that's a bad thing on your car.
Try the fronts at "0" and the rears at "8".
After that I would take the rears down to "7" then "6" etc until she can carry those fronts a while.
Don't worry about the bouncing. If you can drop the 60' a bit by working with the shock settings you won't give a **** how much it bounces.
If the rears don't unload as much as it is now the car won't come down as hard and bounce so much.
Try the fronts at "0", I'll bet with good air you'll see your best 60' yet.

Mark.

NSTY WS6

iTrader: (5)

Looks like to me the car is hooking, and the suspension is too loose. When the rear bottoms out, it bounces up, unloading the tires, and the front does opposite of what the rear is doing. That front end could be unloading the tires. I'd tighten the rear up to keep it from squatting so fast which could keep it from bottoming out and coming back up(which you absolutly do not want it to do). Then, I'd tighten the front up two more clicks for my first pass, If it still bounced some, I'd tighten it up another one or two...

chrismorales75

How about revalving the shocks so they work like they are supposed to, single adjustable front shocks are not designed for drag racing, that's one of the reasons the car unloads the tires.

You keep tightening up the front shocks and it isn't going to transfer weight as much or as quick.

REDGAR

Chris, good suggestion on the "R" valving. I will look into it.

Yup Tim I know you said it, just have not found a multi week gap to get them done. They will come out after running Sunday if I run Sunday.

chrismorales75

BTW I called a place it is about 200 dollars to redo the shocks, they refreshen the shocks, change the valving to "r" type and it sure is cheaper than 290-350 for new shocks.

NSTY WS6

iTrader: (5)

There are tons of people on this board alone that use single adj. fronts, that dont fly up like that and bounce... tightening the settings, will help tremendously while this weekend at the track...before they can be re-valved...

This car apparently has no trouble transfering weight, as it bounces back down immediately, quickness is the issue...

DOTracer

Some really good reading.

http://www.baselinesuspensions.com/i...A_Drag_Car.htm

REDGAR

Hey thanks Todd. I have been looking for something like that for some time.

Did not realize you were over here too.

REDGAR

Last night before I made a pass, I double checked the rear and they were at 9.
Set the front to 12 as I had said I would but the car still spun. Track was pretty cold though so not sure if it was the line or the settings.

Do you think setting the rear any higher and front back to like 4 would be a worthy test?

NSTY WS6

iTrader: (5)

Hard to say, you cant try to fix anything on a "not so good" track surface. Only thing you can do is make the best of it and hopefully your setup works great otherwise..then its easy. But trying new things on something that is already having trouble is hard! Been there before! I'd back the fronts down to 8 to start with, for a good track surface. You want the front of the car to rise gently..then fall gently so it doesnt unload the tires. If you graphed the front end of the car, it would be two smooth inclines meeting at the highest point. And we're talking 60-80 ft this is taking place.

On a "not so good track" its usually better to have the front a lil loose to try and get more weight over the tires, and hopefully keep it there.Being around 4-6 could have helped on the "cold" track. If the back is squatting hard, you could tighten them up a lil more... But if these need to be rebuilt, not a whole lot you can do I guess... hard to say...

That link that was posted is a really good source! For a while, I never saw it anywhere, thought it might be a nice lil secret... but I found out...its not!

Firehawk441

iTrader: (41)

Very well said Mark.

REDGAR

Well I put the car up on jack stands today and I think I found the problem.

The drivers side front shock was leaking and the rebound (extension) is shot. Full tilt at 12 I can pull it out with my bare hands. I cannot push it back in. The right front shock I can pull out by hand at 1 and barely at 2 and at 3, it is impossible.

I the rears seemed okay.

I am still going to send all four out to get rebuilt unless someone says don't do it! All four are out of the car.

Pro Stock John

iTrader: (34)

1) If you have non-R's, have them rebuilt into R's. The non-R's bounce if you set them loose and you can't really do anything about it.

2) Leaky = car bounces, I've seen that happen on numerous occasions.

3) I don't see the need to run fronts too firm, doesn't really accomplish anything. I'd keep the rears at 6-8 stiff, and I run the fronts at 1 to 2 typically.

NSTY WS6

iTrader: (5)

Theroetically, if the track will hold it, you can run the extension on the front stiffer, less up = more forward motion. And if your car hooks, rips the front up, then when the front starts to come down it spins, you again slow the upward motion a little, and it could fix the problem. But if its a "not so great" track condition, loosening them up will generally help...