I recieved a UMI Drag Bar for Christmas and I am in the process of installing it today. I had a question about how the block is supposed to fit the rear end axle tubes. I have the stock rear end and the drag bar was ordered to fit the stock rear end as well. When trying to install it I found out that the block only touches the axle tubing with two of the teeth and not all the way around. Is this common or should it fit tighter and have more teeth touching the axle tube. Also is there any way to fix this?

 

Hey outlaw. Did you torque it down yet? When just finger tight they don't look like they're touching very much. The teeth are designed with a non-circular contact pattern so the bracket can fit a tolerance of sizes.

Let me know.

Thanks

Ramey

 

No we didnt torque it down but we will do that tomorrow. Do these blocks need to be welded to the axle tubes or will the bolts be good enough? Thanks for the help!

 

They are designed to work properly just by bolting-on. Many of our customers choose to add some insurance by welding.

When installing these I like to use anti-seize on the u-bolt threads and revisit a few times the first few miles and give them another turn or two.

If it still looks weird after torquing, you can send me a pic at ramey@umiperformance.com, or give us a call. We'll be happy to check it out.

ramey

ps. our house car has a drag bar like yours and it leaves FLAT. You'll like it.

 

Okay i finally finished getting it installed yesterday and everything seem to be together good. I was adjusting the sway bar as the instructions say to and we got to measuring and now with it set the car goes straight and doesnt pull to the side but the side to side measurement is .5" difference from left to right. The passenger side is .5" higher than the drivers side and i was wondering if that was too much difference or if it should be about the same on both sides?

 

Hey Outlaw. Glad to hear you got your brackets straightened out. I'm assuming they engaged more than two teeth after final tightening?

I'm actually working on a similar drag bar right now for GM G-body cars. When I got to the final link it was around 1/2" longer for the bolt to slide right in. I have the car on four jackstands supported with the suspension at ride height. I'm going to say this 1/2" difference is normal factory tolerance between chassis, diff, sway bar bends, brackets, etc. In other words, no problem-o.

If the car leaves flat you're good to go with no preload. Basically the bar rate is so high (on purpose) there should be minimal body roll. If the car pulls one way or the other, give us a call and we can help you fine tune.

Good luck.

ramey

 

As a tidbit, how do these effect in street driving of the car?

 

Good morning 01ss. A rear drag bar adds a huge amount of rear roll stiffness. This in turn makes the car rotate very easily (i.e. oversteer or loose). Think of it as a "drift" bar.

From a street standpoint your car will definitely feel flat.

Ramey

 

Yes it did engage a little more than two teeth. That's good to know that its not a problem then. We have tried to adjust it and it seems fairly straight. When you say pull are you meaning while driving or from a dig. While driving its fairly straight, but when from a dig the back end slides out a little to the left. This is on the street so that may hurt it a little but should it not launch straight?

 

Hi Outlaw.

You may be able to tune that out with the rear bar end links and help it launch straight. A bit of preload like we're going to talk about shouldn't affect street driving very much. Since the bar is so stiff, keep in mind if you put a ton of preload in it, street driving could be affected.

If the rear is stepping to the left (and front is heading right) you can lengthen the passenger side link one half turn and try launching. If it improves but not enough, go another half turn. Make sure your jam nuts are tight and that you use jackstands.

ramey

 

Sorry, I just realized I put that it slides to the left but I meant it slides out to the right (front heads to the left). Would you just do the opposite to fix that?

 

No prob. Yes, you can just do the opposite and lengthen the drivers side. Also, you can turn the adjuster more than a half turn at a time but since the bar rate is so high I like to err on the side of fine tuning...

ramey

 

Okay I will do that and get it as close as I can to launching straight.

Thanks for all your help!

 

At the track, can this be done on the car, suspension loaded, on the ground? Or, does the car have to be on jackstands for adjustments and fine tuning? I, too have your drag bar on my S60 rear end.

 

Yup, if you can reach it you can adjust it with the car on the ground as you mention. We use L and R rod ends and a hex adjuster for true on-car adjustment.

As a side note, I'm planning on putting our T/A on Longacre wheels scales and getting the corner weights. Then I'll turn the adjusters and see just how much each half turn or full turn throws the corner weights around. Then we can make better tuning suggestions...

We have the S60 as well.

Happy New Year

ramey

 

Reviving an old thread lol

Say I wanted to adjust the sway bar from the front hole to the back. Would I have to adjust length of the end links or should they still go in the back hole without any adjustment?

Also does the actual length of the end links effect anything on the bar?

 

No problem on the old thread.

A small bit of angularity in the end links doesn't hurt anything. We use the same end links for both hole locations. As long as the bar ends up relatively level at standard ride height you're good to go.

The end link length doesn't affect the bar rate (of course you don't want them severely misaligned or pushing at a 45 degree angle on the bar). The main factor affecting the bar is arm length from end link to middle of main tube, bar width - the amount of bar the arm is twisting, and bar diameter including wall thickness.

ramey

 

Ok, thanks