Hey all,

Does anyone have a T56 swap with subframe connectors? How is the fit? Was the install for the transmission difficult due to the connectors? I plan on doing the T56 swap in the future but am worried that the two will interfere with each other.

I'm currently thinking about ordering JEGS bolt-on SFC and either trying to install them myself or having a shop do it for me. Has anyone paid a shop to weld your connectors in? How much did it cost you? Does anyone have any experience with any other brands of bolt in SFCs? I've heard good thing about JEGS but am just curious on what else is out there. Any input helps.

Thanks, Mr.Blu

 

Subframe connectors run along the sides of the car and will not interfere with the transmission. Some rare subframe connectors such as the Alstons had branches that would go to the middle of the car (trans tunnel) and could impact transmission crossmember selection. You will be fine with whatever you choose.

Take a look at BMR, UMI, and Detroit Speed (fab work required). Spend some time using the search function and get ready to read.

 

Alright thanks! I'm still pretty new to the f body platform. I think I'll get some quotes around town and probably get some welded in.

 

There are inner subframe connectors, and outer subframe connectors. The outers are what people commonly use and do not interfere with trans mount. The inner subframe connectors (made by Alston) might battle with space where the T56 trans crossmember bolts up. Just trim things to fit.

See post #373 for a picture, https://www.thirdgen.org/forums/memb...ml#post6220947

 

There won't be any issues using outer SFCs with a T56. I have inners and a T56 with Hawks crossmember in my Firebird. When installing the SFCs, I concluded that the Hawks crossmember would not work with "trimming". I cut and welded it so that it attaches via the bolts used to install the SFCs (prior to welding).

 

The Alston inners have interfered with every aftermarket trans x-member I’ve put in but it’s nothing a little time with a metal cutting blade can’t correct. Outers are no where near the trans.

 

Ah I see, that's pretty helpful, thanks.

 

Thanks. I decided to go with JEGS because the bolt on part is pretty nice and I've heard decent things about them (plus they were $70 cheaper than UMI).

 

Alright thanks. Decided to go with JEGS. Should be here in a couple days.

 

Alright, thanks for replying.

 

Thanks for the response, decided to go with JEGS because I like having the option to bolt them in myself.

 

So with the Alston's are there any clearance issue with stock routed exhaust? I'm on the fence between the Jegs bolt in and the Alston's bolt in. I's rathe go with the Alston's because they actually tie the front and rears together where as the Jegs don't, the tie the rears to the front body near the front sub frames.

 

Do both! But no they don’t interfere with exhaust, they actually hug quite well to the floor pan. I’d suggest welding the Alstons though as one of the mount pads has an angle the bolt passes through and bolts don’t do well with angles. Tightened properly they bend and bent bolts tend to break. You’d need angled washers to fix the shortcoming.

 

i wanted to install the bolt on Alstons then have them welded in and maybe later down the road do the same with the Heidts.

 

IMHO, the ultimate SFC are the Detroit Speed ones. They truly tie into both front and rear subframes and weld along the entire path. The fab work is far more extensive but once done they truly become part of the car rather than a bar that is welded in a few spots. I can get 3 wheels off the ground with one jacking point and the car stays straight as a board.

 

Do they except the factory exhaust routing?

 

They should no problem. When installed they are tucked way high so that you cant even see them without getting under the car and looking behind the pinch weld rail. They actually pass through the floorboards along the sides of the car.

 

Here is an idea of how they weld in. You can see how they run along the sides of the car with feet of welds.