Over the winter i had the opportunity to install a set of UMI Performance's new style front a-arms on my 92 replacing the old style UMI ones i've had on the car since i bought it almost.

For those of you other enthusiasts out there who are thinking of using a tubular front control arm, whether it be for the weight reduction, or because you are a sucker for shiny parts (that are functional), or because you need something that the stock arm just wont provide, these arms may be worth consideration.

The first sytle arms were built well, and fit the car perfectly, but there were some issues with the original arms that were brought to UMI's attention, and unlike many companies these days, they actually listened to us and redesigned the arms correcting the past issues, and improving other areas as well. I found these improvements to be increadily helpful during my winter upgrades for my 92 bird.

New arm vs old arm, the old arm has the aluminum spring seat, i added that, and with the screwdriver conviently pointing to it (forgive the mess, it was a long winter)




so as you can see, its a lot more than a small tweak here and there to make the masses happy, they share nothing with the old arms save maybe a gusset.

What i did not notice when these new pieces were introduced was that on top of all the changes, they arms were redesigned and built out of a larger diameter tubing as well, 1.5" vs the original 1.25".

A spring locator/ramp was added, and a removable bumpstop. A steering stop was also added, and it has built in adjustment. This is a great idea IMHO, and i dont know why nobody had done it before. So many people run larger than stock wheels and being able to move the stop to keep the wheels from rubbing is such a good option to have.

The bit i liked the most was the redesign around the spring pocket, not only does this box the entire arm together in a tight solid piece, it creates more clearance on the rear side of the arm to the tire than a stock arm, and when stuffing a wide front wheel, thats the problem area.


You can see most of the workings of the arm in that pic, the steering stop boss, with a threaded hole inside to accept the aluminum spacers provided with the kit. See how the rear tube (right) tucks right in next to the spring perch, its almost 1.5" more room than the original arm had. Add the gussets and you have a rock solid piece.


you can see here, the main arm it flat, the old ones had a lot more bends, more complication. The new arms also have deeper spring pockets, good or bad? Another simple change i really liked was that the sway bar tab was thickened from 1/8" steel to 3/16. I always thought it looked thin, and apparently i was not the only one. I also just noticed when writing this, the sway bar tab seems to have moved, i will have to check the angle of my end links.

Overall, i are very impressed with the build quality of the arms, and they are gorgeous. I opted for delrin bushings and i installed my own tall balljoints to complete my arms.

 

Install was just like anything else, unbolt and rebolt. I did run into a seeming common snag, and found a pretty simple fix. Its hard to get the springs to stay in the seat while you compress the arm, and it will pop out. I would that simply tying the spring to the back of the seat with common houshold electric wire is enough to hold everything in place while you compress the arm with a floor jack.




just twist it tight with a pair of piers so it does not stretch. worked flawlessly.


I will get other pics, and probably another thread later, but a winter project was installed 18x10.5 wheels on the front of this car, the added clearance of the arms and the adjustment of the steering stop allowed me to do so and still retain a respectable turning radius, similar to stock. Something that i simply could not have done with stock arms.

Final weight, by my scales, was just .2lbs heavier than the 1st style arm too. Not bad for a New a-arm offering so much more than before.

http://www.umiperformance.com/catalo...roducts_id=103

I would highly recommend these if tubular arms are in the budget and/or planned for you build, and big props to UMI for listening to us! These things are beefcakes and i have complete faith they will hold up to whatever you can throw at them (and i plan to do just that)

-Phil

 

Very nice!

 

NICE. Now if they would only add a roto joint option I would be in for a set. With my taller tires I need every bit of adjustability to prevent rubbing. I do like the re-profiled rear bar.

 

Are the delrin bushes the only upgrade option? How do they compare movement-wise with the del-alum bushes?

 

I don't suppose you want to sell the old ones, do you?

 

Wow, big difference indeed. Good thing I waited til they redesigned them. I second the fit and finish, as it truly was outstanding. They just popped right in. The only thing that stopped me was the front springs, but as of a week ago Friday, I got those in as well. Used a member's writeup found on here.

 

They only move on a single plain so there is not need for a bearing since there is no twist.

 

Thanks for the write up Phil! Glad you liked them and we appreciate your feedback... like always.

We feel a Roto-Joint in the a-arm would add no benefit. The a-arm is designed to travel up and down only. The Delrin bushings (which are an option) will allow the a-arm to travel up and down with less deflection than polyurethane or rubber. This is what you want from your front suspension. The Roto-Joints would allow the same up and down movement and would work the same as Delrin but cost more to supply them.

I hope that helps!
Ryan

 

Yup I follow you. Except roto joints would allow me to adjust the length of the a-arm as well as the location of the ball joint front and back in the wheel well. I am running taller than stock (26.9") front tires and in order for them to not rub, I need to be able to fine tune the ball joint location. I can do this with my Spohn Del-Sphere A-Arms. However I really like you rear bar design. With my 10" wheels, at full lock they touch my Spohn a-arms. It looks like I could get a much better steering angle with your arms. I think your current a-arms with roto joints would be the definitive tubular a-arm on the market.

So if you are at all interested, I'm willing to guinea pig a set of these with roto joints. Or perhaps a custom job?

 

Good write up. I didn't realize that they had updates the design that extensively.

 

Seriously good job on these a-arms UMI... I didn't know that you guys changed all of these things on the new version. You didn't just add features, you added strength as well. Good call

 

WOW im sold on them and will look into them over the summer sometime when I get all the other gremlins done on the car

 

Sorry to bring this thread back from the dead, but Ryan you may be able to answer. Phil stated that his A-arms on the new tubes are 1.5, when I was talking to your tech guys they told me they were 1.250.
Can you tell me what size they are and if they have gone back to the smaller size why?

 

I must have looked at an old drawing revision. The current model is 1.500" OD both on the print and on the arms I checked with a caliper a few seconds ago.

Sorry for the confusion.

Definitely 1.500"

ramey

 

No Problem, thank-you

 

Phil, when you changed to the new style a-arm, did you notice if the car stood higher than the old one, since changing mind over, the car is sitting at least 2 inches higher and this is with a BBC in it now

 

I didnt not have any altered height atterwards, I assume you have moved the car since and have the spring indexed ect?

 

Have not moved the car since I am still putting the motor in, springs are indexed, front end feels solid, when you push down on the fenders, even with the BBC and the 2 inch drop spindles that I have always had on the car, car sits as high or higher than stock. I know when I put the in it fell like I had to compress the crap out of the springs to get them in. I am just wondering if they screwed up the spring pocket when UMI made them and put the pocket to high in the A-arm

 

Just a thought. Are the spring all the way in the sprong pocket or is the outside portion sitting on top of the cup? It was a little tricky keeping the spring in the seat when I was assembling them which I noted earlier in this thread.

What spring are you using?
Were the drop spi dles on the car before these arms?
What k member are you using

 

The only thing I change was the A-arms, the springs are the factory Moog replacements, Racecarft k- Member. Springs are seated properly, even the sway bar bushing end links spacer I had to cut down half the length because the UMI a-Arms mount there sway bar attachment point higher than factory

 

The sway bar mount is much higher than stock. I wound up using the shortest end links I could find which have 1" sleeves. They are about perfect, but my car is at the stock ride height, stock springs, anyway, 27 3/4" and 28" fender lip height. I don't know what you would do if you were lower. It also did not line up very well with my sway bar. It needs to be about .75" farther to the back of the car. It was a pita to install the bar.

I did not measure before, but I did not notice a change in ride height.

 

I know my ride height was 26" before the new A-arms, I will measure when the car get back on the ground, but it looks like I will have to cut at least 1 coil to get it back where it was before

 

I would not start cutting spring till the car is on the ground and has been moved around a bit

 

We have done a lot of installs with these a-arms and the a-arms keep the car where the factory a-arms do. So you are good in that area.

 

I am not good, as I said before I have a 2 inch dropped spindles, with the old A-arms I was sitting at 26 inchs with these one I am at over 28. The whole purpose of the dropped spindles was to lower the front end, these A-arms have raised the front end. And the 26 inches was with a SBC, I now have a BBC and it should have been the same or lower with that extra weight, not higher

 

Have you even rolled the car yet?

I would hold your judgement until you roll the car. I speak from experience.

 

We have don't countless installs with these a-arms, including a set a few weeks ago. They have always maintained stock height. The spring perch is at the same height as factory. I am not sure what would have caused a 2" height increase?

 

Springs indexed? These new style arms have the index point on them, unlike the old ones.

 

Springs are indexed, my old A-arms also had stops to index the springs

 

Even when you lower a car off a jack UNTIL the car is rolled allowing the tires and entire suspension to "settle out" the car will not be sitting as it should.

572 id roll the car out of the garage and then back in, then take your measurement.

 

As has been mentioned, ROLL THE CAR AROUND FIRST. The suspension does not settle until you can roll it around because as the arms go up, they rotate around the axis of hte bushings. That means they rotate AROUND it. That means the lower the car goes, the farther outwards the tires go. That means when you have the car without an engine in it, and you put an engine into it, it is going to force the arms up, but the tires themselves are going to grip the ground in such a way that it will not allow them to move outward from the car. They will simply grip the ground where they are and basically bind the suspension until you move the car enough for the track to widen out where it needs to be.

 

Compared with stock ones, what kind of difference in feeling does this make?
More solid? More NVH?
I don't want to increase NVH... like when using delrin bushings.

 

Is that noise , vibration, and Harshness? If anything, I'd say it's a bit smoother and quieter than the old worn out stuff. It definitely didn't get any worse.

 

Thanks for the reply.
So your old ones had stock rubber bushings?
Even with the change from rubber to poly, this makes the ride quieter?

 

The old ones were rubber. Stock? I don't know. I can guarantee that they had at least 70k miles on them. If they were original, then they have 160K on them.
Yes, I'd say the new stuff made it a bit quieter compared to the old worn out stuff. "Worn out" maybe the key words here.

 

Thanks again for the detailed info.
I changed my stock rubber bushing to the global west delrin one at 70k miles (just bushing).
The handling has become superb but I cannot tolerate the harshness, like when the car goes through the manhole that sticks out a bit.

How about this new staff? You are not bothered by the harshness?

 

I don't think it is more harsh. It feels smoother, yet more controlled and does seem to handle better. But once more, that is compared to worn out old stuff - that makes it hard to say if it is because the new stuff is really better or if it is simply because it's all new.
I don't know what a like new, original spec thridgen feels like, so I can't really compare the way my car is now to that.