Freefall

I’m getting ready to order some weight jacks. Does anyone have experience with both UMI and GC? Is UMI worth the additional $200?

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iTrader: (14)

Ground controls cost more because they include a rear setup as well. Umi is just the front.

UMI Sales

We are having pretty good feedback from both street and race customers concerning our weight jacks.

Any questions hit me up at ramey@umiperformance.com

Thanks for looking!

ramey

McLovin1181

I talked to a member here who has run the GC weight jacks for a lot of race seasons.
he told me the GC aluminum rear weight jacks don't hold up to long term abuse.
he switched to the UMI jacks due to their stronger construction.
However GC has the advantage of having a VAST amount of springs and rates to chose from.
UMI told me the springs they used on the front is Semi custom so getting replacements in different heights or rates may be difficult.
they said if i wanted different rates to just cut them. not exactly what i wanted to hear.
the rear UMI springs are Landrum brand power-coated red/black.
I have the Race 1050/200 UMI jacks, but part of me wishes i went with GC due to their spring selection.

Maybe some UMI guys here can shed more light on the spring options.

UMI Sales

The fronts are 8" tall x 5.5" diameter in 850 or 1050 rate, ground flat both ends. Not every oval track company carries them and sometimes one end is open instead of ground flat and many are other colors instead of black, hence the semi-custom.

The rears are a little more common. 10.5 tall x 5 inch, common on street stocks. We have 175 and 200 in stock.

We are happy to source others or you can buy the weight jacks and order separately from the company of your choice.

ramey@umiperformance.com with questions.

Thanks for looking.

ramey

McLovin1181

The front 1050lb spring I got from you guys is only flat on one end though.
It's definitely not flat on both ends

UMI Sales

Oops, sorry, flat on the top, bottom is open to fit in stock pocket.

You should still be able to tune with the wide range of rears available.

McLovin1181

I dug around the spring maker Landrum's products and there are a few lighter and heaver springs that match the O.D and height of the front UMI weight-jack springs.
so All is not lost when it comes to changing rates.
that's good news for me.

CRAMOS78

pros and cons on the 850 vs 1050 spring weight? I'm looking into getting these (front only), mostly for the adjustability, for the new setup. it will be a street, strip type of vehicle. I heard the 1050 had a harsh ride? how harsh are we talking about? I don't want to get the 850's and have it too "soft".....
thanks

UMI Sales

850 would be preferable out of the two with regards to drag racing. The 1050's don't transfer much and even though 850's don't, they're still closer to stock than are the 1050's...

ramey

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iTrader: (14)

I use 1050lb fronts with koni yellows. I would not call the ride harsh at all, honestly the car is quite well composed and comfortable, even on NJ roads

McLovin1181

I have the 1050 fronts and GC Koni Race double adjustable front struts.
It's a pretty stiff ride, but not that bad.
It rides a little harsher than the 700lb Moog/KYB fronts I had before.
The stiffer rear is what's gonna be the most noticeable.
The 200s are way harsher than the stock 100s
And the 200s don't squat under acceleration like the 100s.
I'm using 400lb rears now with UMIs Jack's and it's pretty rough. But it's all worth it when I blast through slaloms at the AutoX.

midnightfirews6

iTrader: (1)

I've had both. The GC front adjusters are a simple threaded rod held to the top plate by a bolt and two washers. The bolt is held in place by Loc-Tite, and I actually had one back out when adjusting. I didnt realize it until I had the control arm off for something else. The top plates deformed a bit over time as well, with the side that backed out being worse, possibly due to the rod shifting sround or jackhammering the plate. Someone on FRRAX reported the same.
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The UMI jacks are much more robust. I bought them because I'd planned on going up in spring rate anyway from the 850's I had with the GC setup, and went ahead and spent the extra for the peace of mind. I'd buy the UMI kit again in a heartbeat.

Nothing against GC as a whole though, I've had their coilovers on other cars and loved them. They do also have some very nice looking short stroke struts for third gens, too...

Qnitro

Im working on getting some UMI's now...

Qnitro

Here is my baby

RoadRace

I run Detroit Speed 950’s and 295/30/18 Hoosier A7s. They are Golden. Their weight jacks are amazing.

SKFengineer

I'm a little late to this party but between the DSE and the UMI weightjacks I went with the UMI for one primary reason. I like using the 3/4 socket on the UMI adjusters vs the allen head for the DSE. It's sort of just a "me" thing but I don't have much luck with allen head fasteners over the long haul and I keep my stuff forever. To the OP I don't have any experience with the GC weight jacks.