Anti-roll bar.

[Rannos]

Went to the track last night after getting the new rearend in. Changing from 3.73 to 4.30 gears and bumping the kit up 50hp. I lost .1 in the 60' and .07 in the 1/8 but gained 4mph. Truck leaves alot harder and squats hard on the rear right almost lifting the rear left. It also drives hard right now which it never did before. I think I need and Anti-roll bar now and was wondering if of yall running 63 to 72 trailing setups had a suggestion on where to find one and suspension simpleton such as myself could use? Thanks for any help.

Jay

[vin63]

Your situation is a great example of what I try to explain to a lot of people that pulling the front wheels high on a launch doesn't always translate to quicker ETs. The increase in torque has exploited the deficiencies in the chassis, creating more movement through the chassis before actually moving the chassis forward.

As you noted, an anti-sway bar will help. Depending on how much room you have, you can run something like this one: http://www.ridetech.com/store/1963-1...musclebar.html

I didn't have much room at the back of my chassis, so I made an anti-sway bar system, using an old leftover sprint car splined sway bar, fabricated my arms and installed it through the frame with a tubular crossmember:


The adjustable sway bar also allows you to adjust for pre-load, etc.

[Rannos]

Thanks for the info. Can I mount the Anti-roll to the rear od my trailing arms? Don't really want to weld to my freshly powder coated rearend. It's the only pretty thing on the truck. If I can go to the trailing arms I may try to fab my own.

Or would a normal swat bar help?

[vin63]

I think the original type of sway bar did mount to the trailing arms. In my case, I just didn't have any room under the frame to mount a bar, so I went through the frame. I ran a Jerry Bickel anti-sway bar on my Super Gas car - http://www.jerrybickel.com/rear-susp...-jbrc1038.html

If you have room in front of your rearend housing, you can mount something like this and have the links connect to the trailing arms...but, it's always better to control the chassis roll at the rearend housing.

[PGSigns]

Couple of things may improve the leave before you go to an anti roll bar. What are you running for shocks and springs front and rear? If not running a fully adjustable shock on both ends that is the first thing I would do. Then if you swap shocks look into putting them behind the housing and getting them stood up as straighter than a factory angle.
Jimmy

[Rannos]

I am running QA1 single adjustables up front and Lakewood 50/50 out back. I did do a shock relocation to get them standing close to up right but they still mount in front of the axle housing. The truck carried the wheels a little before the gear change but not as violently as it does now. Plus it drove straight as an arrow before. Now it drives hard right.after watching the video a friend took I need to add air to the tires. The right rear bunched up so hard the rim was only 1.5" from the track. I'm running 29x14.5 Hoosier QTP'S with 11 psi before my burn out. Going to try 15 psi amd work from there on my next outing.My best 60' was on a 275 pro MT. I may go back to the drag radial if I can't get these tires sorted out.

As for springs I am running the factory springs up front and jeep Cherokee springs in the rear. I need to weigh the truck and get good springs.

[PGSigns]

Soft springs in the rear will work the shock very hard. Double adjustables in the back will help a lot. Until you get the suspension worked out some you will continue to mash the tire in the ground and it will go right. The drag radial may have a stiffer sidewall and that will help. How tight are the front shocks?
Jimmy

[Rannos]

I was trying different settings. I think they are still to loose. That pass was at the 4th setting. Comes up good but lays down fast as well. Here is a video a buddy up loaded of that pass.

http://youtu.be/6cB8Fa0YwEQ

[tinydb84]

Here are a couple I was looking at. I'm not drag racing but they are mentioned on the Yellow Bullet forums:

http://www.rjracecars.com/Anti*Roll-Bars-Prodlist.html

http://www.speedwaymotors.com/Univer...-Kit,4053.html

Welder series site isn't loading now but they make one too: http://www.welderseries.com/blog/

[PGSigns]

Being able to control the rates on the back both directions will cure a lot of what you have going on. The tighter the front is will slow the roll rotation down some. Your idea ontire pressure will also help.
Jimmy

[djracer]

I would go up 1 lb at a time on the tires until the 60 ft falls off then go back 1 step

[Marv D]

Any of the 'Bolt through' torsion bar kits are a total WASTE. Do it once and do it right with a SPLINED bar and ends.
I had a pretty bad setup when I bought my Nova and was doing the body roll pretty bad.

The rear was literally trying to climb up under the car (chassis was rigid, the suspension / 4Link was FUBAR)
I went through a number of the cheap Jeggs through bolt end antiroll / Comp kits and it helped. But the car was totally unpredictable and in one season it would egg the bar or shear the bolt off. It's would drive right one time and spin,, or put it on the bumper the next.
before I cut the 4link brackets out and moved them,, then put a MarkWilliams splined antiroll kit in it.

It's seen a lot of changes and over a second quicker now, but seldom touches the wheelie bars and is dead straight, dead level, .2 quicker to the 60' cone, and a pleasure to drive now

Point is, Like the guys are saying there is a LOT of tuning you can do to get the tires hitting right, (shocks and PSI, tire it's self as in sidewall) and when IF you do need a antiroll bar,, don't waste your time or $ on the cheap junk. Do it once so it right with a GOOD heavy splined kit.

The 3" MW kit may be overkill

But the 1-1/4" kit might be just marginal if you get that thing hooking hard

And in the end,,, the antiroll fixture will try to rip it's self right out of the frame,, so use your rear down bars to help transmit the torque through the whole chassis,, not just some piece behind the cage structure.

[Rannos]

Originally Posted by djracer

I would go up 1 lb at a time on the tires until the 60 ft falls off then go back 1 step

The truck was doing low 1.4 60' before,now its mid 1.5. I changed from a 3.73 to 4.30 and went up by 50hp on my kit and like am idiot changed tres before testing it. Never used these tires before so I went by other people's advice on psi. I think with the tire size and the weight of the truck I am way to low. Plus it hits the tire much harder now. I will definitely try what you're saying.

[vin63]

I have always gone with either a splined torsion-type sway bar, or a welded arm sway bar in my cars because of the failures I've also seen with the compression type of arms that Marv mentioned above.

The reason an adjustable anti-sway bar works well in our trucks is that, generally speaking, there is a large weight bias front to rear, and the bad part of that equation is the front corner to opposite rear corner weight bias. This is a nightmare for suspension tuning with the trailing arm suspension - the NASCAR guys have both a rear double adjustable track arm and sway bar. If the OP sticks with the trailing arm rear for drag racing, an adjustable splined or welded arm anti-sway bar is a great tool without having to spend big money on another set of shocks, etc.

Originally Posted by tinydb84

Here are a couple I was looking at. I'm not drag racing but they are mentioned on the Yellow Bullet forums:

http://www.rjracecars.com/Anti*Roll-Bars-Prodlist.html

http://www.speedwaymotors.com/Univer...-Kit,4053.html

Welder series site isn't loading now but they make one too: http://www.welderseries.com/blog/

[Rannos]

It's weekend I plan to tighten the front shocks and play with tire pressure. Have a few legal street racing events it's next few weeks so can't make big modifications right now. Plus with te current set up it works great with limited prep.

[Rannos]

Have been back to the track a few times. With tire pressure adjustments I have the truck back to mid to low 1.4 60' and about the same 1/8 times. Also found out there were issues with my nitrous holding the truck back. Have fixed that Noe and hope to get new ti.es this weekend. I will also be installing a set of Viking Crusader double adjustable rear shocks before the weekend as well.i will let yall know how it turns out.

[Rannos]

Oh and here is a video of a recent pass. Still twisting up but with the tire pressure sorted out it drives straight.

http://youtu.be/rMWvck1VHhQ

[vin63]

Glad to hear that you got to experience what affects tire pressure and shock adjustments can have on the chassis/ET. As you noted, a lot of energy is being absorbed through the chassis in the form of torsion instead of to the track to move the chassis forward, so there is a lot being left on the table.

The rear torsion bar will also help in the long run to save motor and transmission mounts, as well as transmission cases and general fatigue on the frame.

[Rannos]

I plan on having a cage installed when it's down for the new motor I am currently building. Going to do an anti roll soon as well. I really want to see the 6.4x out of this combo before it goes down tho. So far my best time is a 6.699 @ 102. Still have more in it but want to get the power I make now planted before I turn the kit up anymore.

[Super73]

I bought a set of 1 3/4" rv sway bar bushings and mounted them in the stock location (on the control arms). Took a piece of 1 3/4" DOM tubing mounted in the bushings. I cut arms from 3/16 plate, we led them to the DOM. Drilled holes in the frame and arms connecting rod ends between the two.

It was cheap and very affective.

[Rannos]

Originally Posted by Super73

I bought a set of 1 3/4" rv sway bar bushings and mounted them in the stock location (on the control arms). Took a piece of 1 3/4" DOM tubing mounted in the bushings. I cut arms from 3/16 plate, we led them to the DOM. Drilled holes in the frame and arms connecting rod ends between the two.

It was cheap and very affective.

You happen to have pictures of your set up? May do something similar for now.

[Super73]

I doubt I do, and it is a complete round tube 4-link back half now. I could sketch something out if that would be of help.

[Rannos]

We had private testing at the local 1/8 track last night. I made a few passes with the new Viking double adjustable shocks. My previous best was 1.44 60' and 6.699 at 99mph. Truck went 1.55 60' and 6.645 at 103.9 mph with 30' of wheel hop with the settings Viking reccomended. I made small adjustment from there and it either wheel hops terribly or just blows the tires. It doesn't twist up near as bad now and if I can find the setting to plant the power it should be a low 6.5xx or high 6.4xx. I am starting to think I may have to much gear and am just hitting rhe tires to hard. The best times before was with a 3.73 and I now have 4.30 and this is with a turbo400. The truck is obviously making more power as ever pass was 103-104 but my 60' was all over the place. 1.55 1.50 1.66 etc.

This was the best pass. Wheel hoped a little then spun.

https://youtu.be/LI9VCt-jPN0

[Super73]

Typicallyou mph will be up when spinning the tire. Where did they tell you to set them??

[Rannos]

2 compression and 8 rebound. Tried 0 compression and it didn't wheel hop as bad but spun once it rolled out. Then tried more rebound and it just smooth spun for 50 to 60'