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Discussion Starter #1
Now I have a general understanding of what front end travel is to a drag car. But explain this to me. I have a Chris Alston with single adjustable coil over's. Now the other day me and TOM where working on my wagon and I notice when we jack up the front end. That the front tire's only move down about inch or less. Now I thought you guy's were saying you needed about 2 1\2 to 3 inches of travel. Now is this a good thing that my front end only has 1" or so of movement. TOM thinks this a good thing but I am not convinced.
 

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it should have more......
what shock are you using & what is the installed height ?

The car should have as much travel as necessary to hook up, any more is wasted time.
 

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Discussion Starter #3
it should have more......
what shock are you using & what is the installed height ?

The car should have as much travel as necessary to hook up, any more is wasted time.
I will half to go take a look. Because honestly I bought this car from a gentlmen out of Ohio and he is the one that built the car. But I don't have any traction issue other than every one thought that my car should have 60' better than it did. With the old motor combo the car's best 60' was a 1.41 and alot of my buddies thought it should have 60' a 1.37-39
 

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Discussion Starter #4
I just went and look at what kind shocks I have. And they are what I thought they were. They are QA1 HAL shocks and I notice that the passenger side lower A-arm hangs lower than the driver side. But I am pretty sure that is to compensate for torque of the motor.
 

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Front end travel on a drag car only should help lift the front to transfer the weight to the rear tires to help keep traction. I would only worry about it if you are having trouble with traction. My cavalier is a alston chassis with mustang 2 front end and qa1 singles. Depending on the weather, i lossen the shock for high DA and tighten it for low DA. Loosening the shock allows the spring to help the engine lift the front end and transfer weight to the rear when the engine is down on power due to DA. Once DA starts to drop, early spring or late fall, i have to tighten the shock up in order to keep the car from doing monster wheelies. What is limiting your travel down? a cable? Rod, A Arm, Spring? Shock? You may have to tighten the front spring up so when it pushes to its full extent it is 2 inches down. If it is setup loose it may only have to extend 1 inch till the spring is completely unsprung.
 

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First of all, is this a Chassisworks deal or Alston? ... they are two different companies.

On the travel one thing you can do is measure the total distance from where it sits to the top of the shock/strut, then jack up the car until the wheels hang and measure how much travel (extension) you have.

We run Strange struts and and about an inch and a half extension and compression has about 2" from what I remember. You don't want huge wheelies and only want to carry the tires a couple of inches or so off the track. With everything set up correctly you shouldn't need a whole lot of travel either way. As vic said, loose (more extension) means more front end lift, and tight means (less extension) less weight transfer. The higher the front end lifts doesn't necessarily mean faster 60' times. You can put a cable tie around the shock/strut shaft at right height, make a pass, and see how far the tie moved up the shock/strut shaft to tell you how much extension you had.

Do you have any kind of data logging where you can look at driveshaft speed about 1/4 second after launch?
 

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Discussion Starter #8
First of all, is this a Chassis works deal or Alston? ... they are two different companies.

On the travel one thing you can do is measure the total distance from where it sits to the top of the shock/strut, then jack up the car until the wheels hang and measure how much travel (extension) you have.

We run Strange struts and and about an inch and a half extension and compression has about 2" from what I remember. You don't want huge wheelies and only want to carry the tires a couple of inches or so off the track. With everything set up correctly you shouldn't need a whole lot of travel either way.

Do you have any kind of data logging where you can look at drive shaft speed about 1/4 second after launch?
It's a Chis Alston front clip and as far as data logging. Not at this time but trust me that is some thing I have been thinking about. Year are right about caring the tire's thing. But even with my last engine combo (427sbc 620hp)it would carry the front tire's about a good 8-10" off the ground. But it would only pick the tire's up and then put them right back down. It wound NOT carry them down the track at all. Now mind you I have not done any kind of adjusting on the front or read shocks. Well I take that back I did stiffen the right rear shock up so it was so soft. The car had that normal left front tire
was hirer than the passenger tire. Now it picks both the tire's up at the same time.
 

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Like they all said as long as it isn't spinning don't worry about it. I have a Checkered Racing front end on mine and it had the QA1 shocks on it and it really is/was set up for cruising not racing from them. My car was super inconsistent with the 1-5/8" of travel it had. The upper ball joint was actually binding up when the A arm dropped down. There wasn't enough room in the cup for it to keep dropping. We cut the A-arms and put a couple of degrees of angle on them and now they drop out about 3". I also put Strange double adjustables on it and we are golden. Best thing I ever did. My car rarely ever spins now even on the 275 radials but on cool days when the DA is close to sea level look out. It will pick the front end up even with the shocks tight on extension.
If you want to pick up the 60' time hit it harder if you can and if it's not spinning maybe try to lower your instant center if you can't hit it harder, that way it pushes the car out instead of up.
 

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what i always wuz told

if you help the front of the car go up with travel , then the rear axle will not have to work as hard and apply as much downward force to the tires working against the weight of the car , so the rear suspension doesn't have to work as hard, the front springs are creating lift in the chassis so the ladder bar/ 4 link doesn't have to,,,soooo the slicks aren't planted as well as they could. I'm sure there is a tipping point where more initial front wheel travel might be needed to put this in motion, but more downward pinion angle might work just as good

the rear suspension only has the weight of the car to work with. Some of the old stick cars had no front wheel travel up, but compression for soaking up wheelies

just my .02
 

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Once you get your new engine in, you should 4 corner scale the car so you know exactly what the balance is, where to add or move weight etc. As far as the front left wheel picking up higher, that's normal from torque but you can tighten up the left front shock extension to cure most of that also.
 

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Discussion Starter #12
Once you get your new engine in, you should 4 corner scale the car so you know exactly what the balance is, where to add or move weight etc. As far as the front left wheel picking up higher, that's normal from torque but you can tighten up the left front shock extension to cure most of that also.
Yea I have a buddy who has a set of scales. Which he uses to scale his and his partner's dirt car. So soon as I get the motor in I will have this thing scaled. And my engine builder say's he can get a pretty good deal on some double adjustable AFCO drag shock's. So that should help out a lot.
 

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I will half to go take a look. Because honestly I bought this car from a gentlmen out of Ohio and he is the one that built the car. But I don't have any traction issue other than every one thought that my car should have 60' better than it did. With the old motor combo the car's best 60' was a 1.41 and alot of my buddies thought it should have 60' a 1.37-39
Your 60 foots are off where they should be by about a tenth..

I would only worry about it if you are having trouble with traction.
Bingo...And I'm thinking a wagon with a ladder bar and a 32x14 shouldn't need much..

It's a Chis Alston front clip and as far as data logging. Not at this time but trust me that is some thing I have been thinking about. Year are right about caring the tire's thing. But even with my last engine combo (427sbc 620hp)it would carry the front tire's about a good 8-10" off the ground. But it would only pick the tire's up and then put them right back down. It wound NOT carry them down the track at all. Now mind you I have not done any kind of adjusting on the front or read shocks. Well I take that back I did stiffen the right rear shock up so it was so soft. The car had that normal left front tire
was hirer than the passenger tire. Now it picks both the tire's up at the same time.
You know why it didn't carry it? It's called lack of torque in a usable RPM band..

but more downward pinion angle might work just as good
Pinion angle won't change much at all in a ladder bar car..Leaf springs and slappers, without a doubt...
 

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Is this a ladder bar or 4 link? I bet your 60' times are off because you say it is lifting the tire, then setting it down then moving and not lifting moving setting down. When you scale the car get it as neutral as you can then put some preload on the right rear. Car will go straight. Also an anti roll bar will help keep the car straight when it lifts the wheels.



Oh and if it is hooking now, before you scale it...take many measurement and see where the car is now. Thatway if you scale it and it starts to spin and do stupid stuff you can put it right back to were you have it now.
 

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Discussion Starter #15
You know why it didn't carry it? It's called lack of torque in a usable RPM band..
...
I am not sure I quite understand this statement.:confused: Could you explain. I mean we had the car on the chassis dyno last year. And it made it's peak Tor#'s at 6200 rpm's. And I had the converter set to flash right at 5800 rpm's. So your statement confuses me a little.
 

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Discussion Starter #16
Is this a ladder bar or 4 link? I bet your 60' times are off because you say it is lifting the tire, then setting it down then moving and not lifting moving setting down. .
Yea this a Tria-angulated(SP? or mispernouced)ladder bar car. Let me explain the launch a little better or what I should have said. It pick's the tire's up and roll's forward 6" to 8" and set's them down. Maybe that will help you guy's a little better.
 

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without seeing it i dont know exactly but when it lifts and sets down so fast i am wondering if its unloading? do you have any launch videos?
 

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Discussion Starter #18
No unfortunally I don't. The best I can do is this picture that was taken at Pink's All Out in San Antonino. Also in this pic I had not adjusted the right rear shock. So the car still had that driver side high launch.
 
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