Subframe (and SFC) help, and questions...

[bloopbloob]

I tried to mock my subframes on my car today so i could install them tomorrow, and noticed a few things. The passenger side SFC looks like it will fit great. The driver side does not. First, there is something in the way, just rear of the rear seat bolts. it looks almost like a passageway into the interior, with a plug or something that hangs lower than the floorpan? What is this? second, i'm wondering if my front subrame is bent. the way the sfc lines up, the rear half of the subframe seems to curl up (and away from the sfc as you follow it from front to rear? there is no obvious signs of any other damage, and carfax came up clean. what could cause this? is it a major issue?

also, where should i weld the sfc to the floor? just at the ends, or throw a lot of welds at it wherever i can??
my instructions (which really suck!) say to jack the car up to weld, but isn't this a big ? are there any options to make it easier to get under there?

 

[Fox8950]

Just went and looked at mine (89 GT) and not quite sure what the heck would be hanging on the driver side like that, any chance of a pic? as for the connectors not lining up I feel your pain Lol, I know at least around here its hard as heck to find a nice lil unibody without its frame tweeked a little just from the stock engine torque. I had to form my SFCs just a little to account for this but how far off are ya talking? As for tie in points the way mine were set up just welded to the subframe on the ends (anywhere that SF touched SFC I made a bead ) and then tied into the rear seat mount bolts with a plate welded bout mid way on the connectors

 

[Fett]

What kind of SFCs do you have? The cheap ones, like the ones you find on Ebay, are usually straight bars. Those tend to be interfered with by the contour of the floor pan. Good SFCs, like Steeda or MM full lengths are bent to contour to the floor pan better.

Here are two examples...
Cheap eBay crap....complete waste of money.

Steeda full length.


As you can see, the Steeda ones are not straight. They fit properly. Where as the cheap ones are flat and fit like complete garbage.
Also, don't expect the front and the rear of the SFCs sit perfectly flush with the sub frames. These are old cars and most have had flex issues with them, so don't be suprised if you mock up the rear of the SFC flush with the rear control arm bracket and the front of the SFC has an inch or more of air between it and the front sub frame. Once you weld in one half, you force the other half against the subframe and weld it in place.

 

[88mouse]

The car needs to be level (siting on jack stands is the best way). Then weld them on at both ends. Does yours have the seat brace on them? Not really sure what would be in your way. Can you take a pic and post it up so we can see?

 

[bloopbloob]

ok. i had just heard that you need to do this on a drive on lift (not like a 4 post or anything so its sitting how it rides). so it's better to just weld a couple inches at the ends, rater than stitch along the sfc's where it contacts the sf?

looking at those pics above, i found this pic. See the circle type thing in front of the muffler? thats what its hitting. my cars kinda dirty under there, but it looks like it has tabs that you could push in and pop that thing out on mine, but it doesnt seem to move... maybe its part of the floor pan and i'm just stupid...? it'd be ok just to grind off whatever i need so it sits flush?

 

[88mouse]

Yeah i would just grind that off. As far as how its siting, you just don't want the car to be twisted, cause that is how it will stay after you weld the sfc's on. I would weld the whole thing at each end, won't hurt it any.

 

[Fox8950]

Heh I wouldn't grind those tabs off they hold the cover for that cutout in your floorpan in place. Weird that is in your way though, which kind of SFCs did you get? The straight ones or the good ones contoured to fit like Fett asked. Also this is a very easy job to do on jackstands altho a set of ramps to put the front wheels on would be best as you can't exactly put the jackstand on frame as you normally would, just make sure the jackstands under your rear axle hold the car level.

 

[bloopbloob]

i've just got the straight crappy ones. i wasnt even going to buy sfc's, but i figured for $50 i might as well grab em. they gotta be better than nothing...
i'm a welder/fabricator, so i could modify them to be more like the contoured ones.
i dont think i'll have to grind the tabs, just about a 2" strip right down the middle, leaving the sides and tabs intact, would this be ok?

 

[Fox8950]

I'd think that'd be alright thats just a lip from when they punched the hole, and yah they really arn't that hard to make fit and it sounds like you have the knowhow to do so.

 

[jrichker]

i've just got the straight crappy ones. i wasnt even going to buy sfc's, but i figured for $50 i might as well grab em. they gotta be better than nothing...
i'm a welder/fabricator, so i could modify them to be more like the contoured ones.
i dont think i'll have to grind the tabs, just about a 2" strip right down the middle, leaving the sides and tabs intact, would this be ok?

See http://www.oldwestracing.com/articles/subconn/subs.htm for help with fabricating some subframes and making them fit good.