Hey guys, ive been on n off here for the past year when i ended up trading for an 85 trans am t tops just wondering what you guys think would be the best choice first.. I eventually wanna get both sets of scf, ust cant afford both right now..

 

The key is to have the greatest amount of contact area between the subframe connector and the car's chassis. Looking at the two options you've listed, they both do a good job of this. The BMR pieces with 4 tabs along the length would be good if they are the correct fit for your car. You would need to talk to someone at BMR about that. Otherwise, the UMI, having the extra pieces that tie the subframe connector to the rear crossmember area are a good choice. Definitely stick with rectangular connectors over anything tubular for strength and rigidity. Just noticed, you listed Alston's and not UMI. From what I can tell, Alston's doesn't offer parts for the 3rd gen. UMI does.

 

not alston as in chris alston chassiworks, this alston

http://alstonracing.com/sfc.html

 

I did inner style first, and then outer style 2 years later; some people did the opposite, or both at the same time... No matter which way, it will work fine (just make sure exhaust clearance isn't a problem before you buy)

Some people prefer the outer more and would not get the inner because it doesn't sacrifice ground clearance and ties in the front and rear subframes all along the rocker as well and provides a good solid jacking point.

Some people prefer the inner because it ties the front and rear subframes more directly than the outer style does, but it sacrifices some ground clearance but shouldn't be an issue unless you are "stupid low" (as someone on TGO put it) but it doesn't stitch weld along the rockers like the outers do (I know SPOHN's outer style can be stitch welded, not sure about BMR or others, you'd have to double check that). Inners are cheaper to buy, and cheaper to install too, that is also a factor. The choice is yours but either will re-inforce the subframe in the way that I think you are looking for.

 

I was looking at the bmr but I am going with the umi

 

I see I had the wrong Alston. These are bolt in connectors, which I have never cared much for. The bolt holes will elongate over time and the connectors will lose their effectiveness. The UMI are a good choice. Rectangular tubing and it looks like you can stitch weld them along the pinch weld. Plus they have the added pieces to tie in the rear cross member.

I was fortunate to have built my car back when Southside Machine was making subframe connectors for the 3rd gen. They made a full kit that even included ladder bars for drag racing only applications. Their connectors are built to actually become part of the chassis. The one additional job I may still do is to tie in the rear cross member by adding a brace on each side. Be sure when you install the connectors that you pre-grind the areas where you will be welding and test fit the braces. I had to do some work on mine to get a perfect fit. I also added butrices to the area at the front of the pass side connector to increase the contact area for added strength. You don't want the welds to tear out over time as this will cause real damage to the chassis. Then seal all the welds with chassis black epoxy.

Have the car supported by the rear axle and the front lower control arms as close to the wheel as possible so that the frame is sitting in its natural position. Any arc in the chassis when the connectors are welded in will become permanent.

 

They can be welded in, in fact the bolt holes make perfect holes for plug welds.

IMO the UMI are not great eikther, that stupid little curved seperate piece that goes under the exhaust...etc.

I recently cut off the SSM bars and the accompanying crossmember. Didn´t care for them at all.

 

Yeah i read somewhere on here the you could weld in the bolt ins witch is what i was planning to do.. The car's gonna be a DD during the summer months, its got a 350 vortec carbed n a t5 tranny

I've got a couple friends that are pretty good welders and yeah i did see a post somewhere on here about getting it on jackstands with the suspension loaded to get em welded in right.. Hopefully ill have access to a pit to make things a whole lot easier!

Im not too concerned about ground clearance since my gfx kit is about 6 inches off the ground, i just want the car to last and not twist like a pop can

 

Ill probably be goin with the outter style first.. Thanks a bunch for the quick replies guys!

 

Anyone who can weld them in can also make them from scratch for a fraction of the price.

 

I sent the crossmember and the ladder bars back as I wasn't interested in altering the rear suspension into a drag race dedicated setup. I really like the SSM connectors themselves. They practically convert the chassis into a full frame. I place the lift pads on them when I raise the car on a two post lift. It does appear that you can weld in the bolt in style. I just prefer the style that stitch welds along the pinch weld as it seems to be more solid.

 

Can't remember what the ssm sfcs look like, anyone got a pic? I liked the kenny brown double diamond ones

 

I have the outer style SFCs by BMR. They are so big and beefy, I am having a hard time convincing myself that I would still need a set of inner connectors.

 

how about both????

 

yuuuupppp

 

I have a question about welding these in. I have the altsons sub frame connectors. Does the cars weight need to be on the tires when welding in the inner styles? I know it should be when welding in the outer style.

 

Yes. Regardless of inner/outer or make/model of the car.....Weight needs to be on the suspension (tires). A drive-on lift is the easiest.

 

Thanks. Can't wait to get these things in. I'm starting to prep them right now.

 

Twin_Turbo and 88fastgta who manufacutered your inners and outers?

 

Alston inners umi outers

 

Looks good....thanks. I have a single cat in the stock location. Do you think that UMI outer will allow room for it?