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View Full Version : Lift arm or pull bar?



Dirtmod13
01-25-2015, 03:16 PM
Working on setting up our new rocket and a friend said a pullbar gives more traction. Any one tried both? Results...

save the racers
01-25-2015, 05:38 PM
I've tried the rayburn style pull bar and lift arm on the same car.The pullbar gave good traction but had a very narrow sweet spot.The lift arm was easier to drive and tune and was what we stuck with.

MasterSbilt_Racer
01-25-2015, 06:38 PM
Working on setting up our new rocket and a friend said a pullbar gives more traction. Any one tried both? Results...

A pullbar gives quick, instant traction that fades more quickly than a liftbar. It typically makes it very difficult to accelerate and steer at the same time. I don't really see it being compatible with the current 4 link at many tracks.

DirtRacer9x
01-26-2015, 04:50 PM
Lift bar and tied down front end drives off way harder.

MasterSbilt_Racer
01-26-2015, 06:39 PM
Lift bar and tied down front end drives off way harder.

Not really. Better corner speed makes it come off the corner. Pullbar car would win a drag race. Tied down 4 link won't go without lateral acceleration.

DirtRacer9x
01-27-2015, 05:46 PM
Not really. Better corner speed makes it come off the corner. Pullbar car would win a drag race. Tied down 4 link won't go without lateral acceleration.So you're telling me you're going to achieve more weight placed on the rear tires with a pull bar than a lift bar?...

MasterSbilt_Racer
01-27-2015, 06:16 PM
So you're telling me you're going to achieve more weight placed on the rear tires with a pull bar than a lift bar?...
Quite possibly. Neither device attaches to the chassis in front of the center of gravity. The pullbar will raise the rear of the car more allowing for more front to rear weight transfer. In your example, tie down shocks on the front will kill weight transfer.

Matt49
01-27-2015, 07:28 PM
MasterSbilt_Racer is correct. Ratcheting down the front end doesn't allow the weight transferred to the front on entry to transfer back to the rear on exit. Simple physics...the rear tires need more load to create forward bite. The ratcheted down front end deal works best on momentum race tracks where you don't need as much forward bite. You keep the car at an angle of attack that promotes aero. On a stop and go race track, that is a junk setup.

A lift bar and a pull bar can both create mechanical loading of the rear tires but the reason you can get more "drive" out of a pull bar is because it can be moved further to the left. That's a bit of a problem for a lift bar which really can't be mounted any further to the left than the right side of the drive shaft.

drtrkr244
01-27-2015, 09:32 PM
Matt49, I saw a dlm in the late 80's, with a pullbar mounted to the left side of a quick change. It had a mount off of the left tube and used the 90/10 plate for the right mount. Yes, it was on the short side but the car had unreal drive. I have always wondered when someone was going to duplicate that on these current setups.

Matt49
01-27-2015, 10:23 PM
Matt49, I saw a dlm in the late 80's, with a pullbar mounted to the left side of a quick change. It had a mount off of the left tube and used the 90/10 plate for the right mount. Yes, it was on the short side but the car had unreal drive. I have always wondered when someone was going to duplicate that on these current setups.

Since the LR behind setup, most cars have more traction than they know how to use. End up tight-in/loose-off if you know what I mean.
The pullbar makes it worse. JMO. I've never seen anyone do anything but struggle with a pullbar on a LR behind late model setup. It's way too much traction way too fast even in the slickest of conditions. You end up just chasing your tail...literally. JMO but I would avoid it.

Dirtmod13
01-27-2015, 10:23 PM
[QUOTE=A lift bar and a pull bar can both create mechanical loading of the rear tires but the reason you can get more "drive" out of a pull bar is because it can be moved further to the left. That's a bit of a problem for a lift bar which really can't be mounted any further to the left than the right side of the drive shaft.[/QUOTE]So on a shorter track would you run the pull bar and on bigger momentum tracks run the lift bar?

DirtRacer9x
01-28-2015, 05:02 PM
So had anyone seen a late model pull the front tires off the ground with a pull bar? If so if like to know because I don't know any that have. Lift bar I see it many times. Not saying this is fast but I'm trying to refer back to loading of the rear tires pull bar vs lift bar.

Dirtmod13
01-28-2015, 06:20 PM
So had anyone seen a late model pull the front tires off the ground with a pull bar? If so if like to know because I don't know any that have. Lift bar I see it many times. Not saying this is fast but I'm trying to refer back to loading of the rear tires pull bar vs lift bar.Or is it shock package with light rebounds that allows the fronts to lift off the ground?I know with our drag cars a near zero rebound will let any old car lift the front wheels with a stout small block.

Dirtmod13
01-28-2015, 06:21 PM
Then what about moving shock/spring on lift arm closer to the rear to give it more leverage?

DirtRacer9x
01-28-2015, 08:48 PM
These are all heavy tie down cars as well doing this.

MasterSbilt_Racer
01-29-2015, 08:14 AM
So had anyone seen a late model pull the front tires off the ground with a pull bar? If so if like to know because I don't know any that have. Lift bar I see it many times. Not saying this is fast but I'm trying to refer back to loading of the rear tires pull bar vs lift bar.

I have seen a Rayburn do it, yes.

I hope everyone I race against puts a pullbar on their 4 link car.

RacerX10
01-29-2015, 07:29 PM
I've been fighting with a pull bar on a 4 link car for years. Giving up and going to a vanilla rocket setup.

Ain't nobody got time for that :)

dirtrace09
01-30-2015, 08:36 AM
So had anyone seen a late model pull the front tires off the ground with a pull bar? If so if like to know because I don't know any that have. Lift bar I see it many times. Not saying this is fast but I'm trying to refer back to loading of the rear tires pull bar vs lift bar.

Both devices are trying to do the same thing in a different way. The idea is essentially to plant the rear tires as the pinion tries to rotate up by placing the force downward. The pullbar's angle and placement make a big difference as to where and how it applies the pulling force to the chassis. The liftarm is using a spring and shock combo to use a lifting effect on the chassis. That is also effected by the distance that it is placed from the pinion. Both have there place in the right situation. The pullbar is effective on a swingarm situation or a clamped up car because it allows the spring ahead to also figure into the equation. Think of what the car is trying to do under a full throttle load, then work forward from the rear of the car. Shocks, springs, weight placement, type of suspension, etc... all have to be taken into consideration to make a car consistent and driveable.

Dirtmod13
01-30-2015, 09:23 AM
Both devices are trying to do the same thing in a different way. The idea is essentially to plant the rear tires as the pinion tries to rotate up by placing the force downward. The pullbar's angle and placement make a big difference as to where and how it applies the pulling force to the chassis. The liftarm is using a spring and shock combo to use a lifting effect on the chassis. That is also effected by the distance that it is placed from the pinion. Both have there place in the right situation. The pullbar is effective on a swingarm situation or a clamped up car because it allows the spring ahead to also figure into the equation. Think of what the car is trying to do under a full throttle load, then work forward from the rear of the car. Shocks, springs, weight placement, type of suspension, etc... all have to be taken into consideration to make a car consistent and driveable. That's what I was wondering. With this new limited class, our springs are in front of axle. Left front is clamped. So that would definitely wrap into the coil over when on the gas. Havent looked at the right side yet, Think that should be clamped as well? Im assuming with it clamped it would put more pressure on that spring (as well as left) and technically should loosen it a bit. Am I on the right track here?

SuperEight
02-08-2015, 11:49 AM
So had anyone seen a late model pull the front tires off the ground with a pull bar? If so if like to know because I don't know any that have. Lift bar I see it many times. Not saying this is fast but I'm trying to refer back to loading of the rear tires pull bar vs lift bar.

You can have too much of a good thing. Setting the car up to lift both front tires off is ludicrous? You ever see Moyer or Bloomquist or anybody that race for a living strive to lift front tires off the track? I've seen some pics taken in odd situations where this happened, but they weren't headed to the front, which last time I checked was the goal...


I have seen a Rayburn do it, yes.

I hope everyone I race against puts a pullbar on their 4 link car.

I know right, LOL!
Some combinations don't go well together. I think a 4 link works its best with a lift arm and Z-link stuff can benefit more from the pull bar, its that simple. I think the Z-link stuff can run with a lift arm too, but 4-link and pull bars just get kinda radical.

SuperEight
02-08-2015, 11:59 AM
That's what I was wondering. With this new limited class, our springs are in front of axle. Left front is clamped. So that would definitely wrap into the coil over when on the gas. Havent looked at the right side yet, Think that should be clamped as well? Im assuming with it clamped it would put more pressure on that spring (as well as left) and technically should loosen it a bit. Am I on the right track here?

If you've gotta run in front on both sides, run LR clamp and RR on swing arm or birdcage. This will promote better drive under accel and promote better side bite on decel than the clamp. JMO

popkorn42
02-09-2015, 08:33 PM
I'm thinking it's time to dig out the old TRI CITY BUGGY. .. cantilever shocks ...lay down lift arm
On the left side of the QC
where's Gary Oliver when we need him? ?

junebug
02-09-2015, 10:16 PM
I thk a big question is what tires do u run if super hard tires are mandatory a pullbar might not be bad...both can be way too tight if tuned wrong and both can be awesome if tuned right...u can make either work but I think the lift arm is probably better if u want a car that isn't on the edge of pushing most nights

Racerguy27
02-18-2015, 01:48 AM
SuperEight

Do you think that swingarm right side creates more sidebite on a slick track than four bar spring floated on birdcage (front). Anyone else can chime in as well thanks

Racerguy27
02-18-2015, 01:51 AM
For you guys that think lift arm is the way to go. Do you guys think a lift arm would be better on a spring behind modified as well since they have smaller tires?

MasterSbilt_Racer
02-18-2015, 07:57 PM
SuperEight

Do you think that swingarm right side creates more sidebite on a slick track than four bar spring floated on birdcage (front). Anyone else can chime in as well thanks

Not a chance.

MasterSbilt_Racer
02-18-2015, 07:58 PM
For you guys that think lift arm is the way to go. Do you guys think a lift arm would be better on a spring behind modified as well since they have smaller tires?

I have way more LM experience than mods, but I say yes.

Racerguy27
02-19-2015, 04:55 AM
MasterSbilt_Racer

what about z link would it have more side bite? I see a lot of guys running 4bar left and Z link left?
Thanks