Installing Subframe Connectors

[tatertot91]

Seen a few people asking about Subframe Connectors or more commonly known on the site as SFCs so figured i'd take some pics of my install and give everyone a quick run through of how to install them. There are weld-on and bolt-on style SFCs and they come in 2 point and 3 point styles, for my install i chose 3 point bolt-ons from UMI (Great piece!)
Advantages to bolt ons are basically anyone with a jack and basic tools can install them, and they can be welded on at a later time if desired
Just got through going over major oil leaks so the bottom of my car is a little dirty, try and ignore the filth lol

Text in blue is for 3 point SFCs only

Here is a pic to show what i was working with


Started up by jacking the car up off the ground, rested the front on blocks and chocked up the wheels so the car wouldn't roll
Always exercise extreme caution when jacking up your car, use jack stands and it never hurts to have a buddy help out

Worked on one side and completed that SFC before moving on to the other, here i'll be showing the passenger side install
With the front end on blocks i lifted the rear of the car by the body and set it on jack stands
Font end suspension is now loaded with the rear suspension dropped. Then placed my floor jack under the rear end and held the rear in place, doing this kept the rear from moving as i unbolted the pass. side LCA. Here you can see i used the shock mount as a lifting point, i only supported the weight of the axle here, not the whole car


Then went to the LCA and removed the bolt holding it to the body as you can see in these two pics 18mm Wrenches come in handy here



With the LCA bolt out the Rear mount on the UMI SFC simply slips over the mount for the LCA


I then placed the LCA back in its original location and reinstalled it using the replacement hardware included with the UMI kit, do not tighten yet


Being that these are 3 point the tunnel brace has to be removed (4 - 13mm bolts) to make way for the center SFC mount, the brace then gets reinstalled on top of the SFC as you can see in the pic below. These are the last bolts to go in


Next i installed the front mount. UMI supplied me with 4 bolts, washers, and 2 mounting plates, here is what was needed for the pass. side



The mount simply gets slid into the body shown here


From here on simply hold the SFC up to the body and put the 2 front bolts in place
Was a bit tricky getting the bolts to line up without the mount moving around but managed to get it lined up after some finessing, do not tighten these bolts yet
Once that was bolted up i reinstalled the tunnel brace using the replacement hardware by UMI (this can be done once both driver and passenger SFCs are installed, again do not tighten yet)


Once the SFC was in place i jacked up the rear of the car and placed my jackstand under the axle to put the cars full weight on the suspension
With the suspension loaded the bolts can now be tightened. UMI recommends torquing the Rear LCA bolts to 75 ft/lbs and if and noises are heard to then tighten them to 100 fl/lbs
Front bolts can be tightened up as well as the Tunnel mount bolts

All the same steps can be repeated to the other side

Here are a few pics of them installed under my car




Ground clearance is excellent, have well over an inch of clearance over my stock y-pipe
I'll be sure to get some side shots to better show my ground clearance and if you have any questions just lemme know
Hope this helps some people out

[Knight]

Good write up, Alex! I know exactly what you meant by "finessing" too. Mine did as well. But I agree with you, UMI makes a great quality product.

[Cutlass]

Well done. Added to stickies in Gen Help!!

[UMI Performance]

Excellent job!

[tatertot91]

Thanks guys

[cancam99ss]

You need lca and phb

Pm me info and price of where u got the sfc

[UMI Performance]

You need lca and phb

Pm me info and price of where u got the sfc

The SFC's are UMI brand and we are a sponsor here Part # 2004 and they can be seen here- 1993 - 2002 GM F-Body 3-Point Subframe Connectors- Bolt-In [2004] - $339.99 : UMI Performance, Inc.

I hope that helps!
Ryan

[98maro]

great write up alex!
this exactly what i was looking for..

thanks!

[024mula]

Great write up

[cancam99ss]

Alex just ordered mine! Wanna help me on the install

[tatertot91]

great write up alex!
this exactly what i was looking for..

thanks!

Great write up

glad I could help out

Alex just ordered mine! Wanna help me on the install

Yeah dude, lemme know when u get em

[cancam99ss]

Ohh will do

[1WickedWS6]

This is a great explanation man! Definitely gonna help me when I go to do it. Just a quick question though. I'm guessing by the price you used the steel ones and I was wondering if you thought if the chrome moly set was worth the extra hundred bucks.

[tatertot91]

In my opinion the chrome moly is overkill for most street cars unless you do a lot of auto crossing. If its weight you're hellbent on saving than go for it but the weight differences are minimal. The idea behind chrome moly is strength, like I said my car if primarily street driven so it would be overkill for me. What are your goals for the car? Drag, auto x?

[MAXX2]

We named this our OCF, for Occupant Compartment Frame. 2-1/2” x 2-1/2” x ¼” Steel, bolted to ¼” steel plates welded to interior sections of the floor, plus an additional ½” steel plate for added rigidity, with the roll cage welded to the OCF. The powder coat color is from UMI, and yes, they are awesome to deal with. They have shipped our Engine Bay Brace (Pic next week), and we soon will have our Front Suspension/K-member setup for our Traditional Small Block installation.
Not overkill at all, as this is the future of what sanctioning bodies will require for passing tech.

MAXX

[MAXX2]

[Questioner]

so ...after i bolt the sfc's up just enough for movement and frame shift, i can lower the car off the jacks so that the car is on its own weight and then tighten the bolts to proper torque?

[Cutlass]

yes. that's exactly the idea

[pajeff02]

^^ Agree. That will work and you can bounce the car on its suspension a bit to settle everything into place too.

[freaky57fast]

I'm so glad I ran into this thread! I just ordered my sfc and a new torque arm lol. I think I'll need to put mine up on dang 10" blocks, I hate being so large sometimes...