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 Post Posted: Sat Sep 04, 2010 4:24 pm 
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Location: Tell City, IN
I am having trouble hooking. One minute 1.32 60' the next 1.36
I have tried many different air pressure settings and burnout lengths. No good results.
So here is the normal way I set it up..
I adjust the bars to the same length
I bolt them in place with no pre-load
I set my pinion angle to +.5° Half a degree positive

Am I doing something wrong? It goes straight just will not hook very often.
I also have the bars in the middle hole which puts the flat part of the ladder bars about 1° down

Thanks in advance for info..

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1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
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 Post Posted: Mon Sep 06, 2010 6:23 pm 
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Jody,

You might dig into the shocks, and springs both rear, and, front, you may have something going on or wearing out, or just tired like a spring. Let us know if you find anything. One more thing, how did the heim joints look, and the bolts that go thru them? How is the track surface, is it going away? balled up or show bear spots? Just things to look at...

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 Post Posted: Mon Sep 06, 2010 8:39 pm 
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I have pulled off the shocks and they are set correctly, seem fine. My Heim Joints are all solid and free. The suspension is free front and rear... free moving. The track surface seems pretty good everyone is running their best times and 60' while I am left spinning. I did find one thing.
The rear end has been making a noise the last 3 passes I made. So I tore open the rear end cover to find the pinion gear missing alot of teeth.. So I am thinking it may have been contributing to the spinning. So I stuck in a set of 4.56 gears I have been wanting to try anyway. I had 4.88's in it. What it seems like to me is it is hitting the tires too hard not letting it hook. So my next pass I make I will leave it like it is, if it spins I will lower the rear shocks to take some hit out of it, see if that helps.. if it don't then I will go the other way and raise it up 1 hole from where it is now and see what that does. What makes me thing that I am hitting the tires too hard is if I turn the launch up a little it gets worse..alot worse.
Does this sound like a good place to start?

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6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post Posted: Mon Sep 06, 2010 10:01 pm 
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I think you may have got to the point where the ladder bars just aren't enough for the ET you are running. It also could be the chassis flexing somewhere. When I got the Pinto running quicker than 6.20s it became inconsistent and a little hard to handle. It got bad enough the last season I raced it with ladder bars I tied the front end down, added some air to the slicks and let it spin a little. Believe it or not it was easier to drive and more predictable like that. That winter I cut the chassis out from the firewall back and went to the 4 link. When I got the frame rails out I could actually see where they were bowed slightly at the ladder bar crossmember. That car had evolved from a street car and when I tied the frame together I had laid the box tubing flat so I wouldn't have to notch the floor. Then later when I added the ladder bars I just added the crossmember to the existing frame connectors. Not really the best way to build a race car but it seems like a lot of cars get built like this. It's OK when you're not making a whole lot of power but most of us are never going fast enough and as we make more power we find the car we have been "adding to" just isn't quite enough.

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 Post Posted: Mon Sep 13, 2010 5:21 pm 
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Well I swapped in a set of 4.56 gears and I was still spinning. I lowered the shocks 1" and it seemed to maybe help a little. So the gears hurt the performance. It ran a best of 6.420 with only a 1.37-1.38 60' Spinning every pass. So now I am installing a set of 5.13 gears.
Also I am going to lower the front point on the ladder bars to about 1" lower than where they are now. I don't want to go a full hole down and there is room to make another hole so I am going to drill a hole basically between the 2. If that don't work I will go the other way.
I don't know if I am hitting the tires too hard or not hard enough. I don't know how to tell the difference. Anyone know? Thanks

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post Posted: Tue Sep 14, 2010 7:44 am 
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By your 60 ' falling going from 4:88 to 4:56 gears you would have lessened the hit / power the suspension see's so I would think you need to raise your ladder bars without seeing a video.

I personally don't think you are running too fast for ladder bars my self , but your chassis could be flexing and causing problems as Chuck suggested.

Here is a friend of mines car we just videoed a couple weeks ago and if you look it has old white letter good years on it and they are shot =; . Its a back half ladder bar with a blown 547 cubic inch big block . It had a 1.18 60 in this video.

http://www.youtube.com/watch?v=Oa3bm8NS ... re=related


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 Post Posted: Tue Sep 14, 2010 7:37 pm 
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Here is a link from early last year where it was working.. I have changed nothing but the tires to a different set of exactly the same size.... the end of the video is in slow motion. looks like it actually bounces after the hit?

http://vimeo.com/4422136

So I now have the gears in the truck and I have went the way you suggested and moved up about 1" on the front of the ladder bars. I will also take the shocks off and switch sides and make sure they are set to 50/50 I guess....?

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post Posted: Tue Sep 14, 2010 7:59 pm 
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From the slow motion video I can't tell that you have much suspension action at all , so I would still suggest raising them. I also rotate my slicks every 10-15 passes.

I don't know what kind of shocks you are using double adjustable or single ? I would start at about 50% on extension and 60 or so on compression if you have double adjustable and adjust them separately one at a time while testing to see what happens.

The more I mess with suspension the more I understand that the weight distribution - power ratio is so much a bigger part of this than the suspension itself. Anyone can move ladder bars to a different hole and if one of them don't work its got to be the other 2 causing the problem , provided there is no binding , shock, track or tire problem

Its hard to believe it could go from hooking like it was to not hooking with just a tire change though.

EDIT

The more I have set and thought about this I wonder if your front springs are fatigued , you are getting a lot of "help" from them and I am sure the huge wheel stand landings would weaken them over time.

Imo When you get to a certain power level you are gonna have to limit the amount of front suspension travel you have and let the chassis work because one of these days the front end is not going to come down like you want it to.


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 Post Posted: Tue Sep 14, 2010 10:20 pm 
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ky mustang wrote:
The more I mess with suspension the more I understand that the weight distribution - power ratio is so much a bigger part of this than the suspension itself.

Agree ... I've found exactly that myself.

What are your weight % Front-Rear? Is your engine set back? With nose heavy cars (or trucks) you have to hit the tires hard and get them planted long enough to get the front up in the air. Then you have to keep it there until the tires are past spinning. Watch NHRA SS cars, they have easy front travel to get the nose (weight) up in the air and onto the back tires. Raising the front weight is another way of helping that transfer. If your front has settled to a lower stance on the line it could be enough to reduce transfer to a marginal traction situation.

Rick


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 Post Posted: Wed Sep 15, 2010 3:50 am 
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Thanks for the advice guys. As far as weight the truck is 600 Lbs nose heavy. It weighs 2865
The front springs are Moroso Trick springs with a max weight of 1660Lbs on the frontend. That is about what it weighs there. The tires are still off so I will rotate them again. I have done this about 30 or so passes ago. My shocks are cheap 3 ways single adjustable. You know the kind you push together and turn 3 clicks.. As far as it hooking and now not really confuses me.. (That was one killer set of slicks? lol) It always has done better on a cold track if that makes any difference.. most probably do but thought I would throw that in there too.

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post Posted: Wed Sep 15, 2010 1:09 pm 
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Jody, how many passes do you have on those rear tires, front shocks, and front springs? THEY (the tires) may be going away also :-k I am also agreeing on the front springs/shocks, and your truck leave's very nicely and I see just a tad of seperation on the hit but it then looks to just carry it out evenly, but you are loosing et by going up and not straight forward #-o but them wheelies do draw attention \:D/ \:D/
Why did you change the gear ratio also? did you not have the same ratio at home to replace them with? THAT may also be why you lost some time. I would try another of the same ratio gears, it may or may not help but it seems your in a process of elimination now, and just need to find the bad link (sorta speak)in the system. Good luck and keep us informed.

Elky

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 Post Posted: Wed Sep 15, 2010 5:29 pm 
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Will keep you guys informed. The reason I changed the gears is because I broke the Pinion gear.
I guess I had them setup wrong from what I was told. So I had access to the 4.56's and thought maybe it would like those...it didn't so now I will try the 5.13's before I go out and buy another set to see if maybe these will do. I have always ran the 4.88's and most likely will end up back there unless these make a big difference.

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post Posted: Sat Sep 18, 2010 12:17 pm 
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Well got to the track last night.. wasn't the best night.
I launched at 4000 like normal it ran
6.40
6.42 both with 1.36 60'
Then I upped the launch to 4400 and it went a
6.35 with a 1.35 60' kinda spinning.
So I played with the air pressure. it went a
6.36 with a 1.34 60' Long downtime my friend rolled his 69 Dart... =P~ he is ok though.
with the long downtime I think the oil got thick and it ran off it ran a
6.41 with a 1.35 60' so I decided to drop the launch down to 4000 and up the air back to normal it ran a
6.35 with a 1.33 60' but kinda pulling the front high then to the right..
My final pass for the night was a ride, it was worse this time and nearly crossed the line but managed to stay in it... It ran a
6.38 with a 1.34 60'

So something is driving it to the right. I got home at 1:30 unloaded it and as I was looking at the truck from the rear...it was sitting about 4" lower to the passanger side rear.. The tires looked ok and the front wheels were straight so I guess I have something bent or broken.
I will take a look see maybe tonight or tomorrow. I am still spinning and I believe it is squatting even though I went up a about an inch on the ladder bars. So I may need to do some more adjusting.. don't know. could all have to do with whatever is bent or broken..

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post Posted: Sat Sep 18, 2010 12:58 pm 
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Location: Tell City, IN
I got curious.. I went out there just to see. The top ladder bar bracket on just the passenger side is starting to rip off. It is just the passenger side on the outside section.
So I will need to pull the rear end out and box all of that in like I should have done in the beginning. Will see more when it is out.... [-(

_________________
6.11@110 Gas
1.3718 Sixty Foot with the rear wheels Gas

6.07@110 on Alcohol Injection with a 4-link 4-6-12
Best 60' 1.2537 Alcohol Injection 4-29-11
Thru the Mufflers!!


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 Post Posted: Sun Sep 19, 2010 7:22 am 
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well that kinda explains some of your problem then, good thing you found it that could have made for a hairy ride O:) .


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