tubular subframe?

[shooff82]

Has anyone tossed around the idea of fabbing up a tubular front subframe? Maybe one with integrated subframe connectors? Being fwd, these cars seem a little nose heavy. And a little more room would be nice for exhaust or turbo routing might be handy.

 

[kevinspann]

They have, but a tubular subframe will not be as strong as the stock one, nor wil it perform the same in an accident. By the time you actually build one...it probably won't be much lighter than the stock one...the time involved isn't worth the slim to none benefit. There are easier ways to get weight off of the front end

 

[Jonny Cash]

Have you considered turning the motor 90? That would be alot more rewarding.

 

[HotRodKid]

They have, but a tubular subframe will not be as strong as the stock one, nor wil it perform the same in an accident. By the time you actually build one...it probably won't be much lighter than the stock one...the time involved isn't worth the slim to none benefit. There are easier ways to get weight off of the front end

shall i remind you that the front subframe is only as strong as the small areas of SHEET METAL its attached to the vehicle with?

A tubular subframe will be exceptionally strong if designed properly.

and for that matter, its been done already. One of the AIV's got an aluminum subframe that was just as strong as the originals AND a MASSIVE amount lighter.

 

[SuperHO]

****, even a boxed aluminum subframe following the exact dimensions of the steel one'll be significantly lighter. i've thought about it, but little else. i especially think about it when following some GM vehicles with their aluminum sub-assemblies peeking out from under the car.

 

[kevinspann]

A tubular subframe will be exceptionally strong if designed properly.

Designed properly would be the key

 

[shooff82]

I've been thinking about it for a long time because its been done a gazzilion times in fox cars. And a stock kmember in a fox vs a tubular one, there's tons more room and up to 30lbs lighter(with tube control arms)and stronger I believe. How about a full length tubular frame? It wouldn't be lighter than the stock cradle, but it would significantly stiffen up the whole car and help to distribute weight more evenly. Wouldn't it?

 

[93rev2sev]

Ya, for a lot of money!
But if you got the money and the time, you can do some amazing things.

 

[St Louis SHO]

I got flamed years ago for mentioning this....

 

[HotRodKid]

Designed properly would be the key

if you switching to aluminum, yes, it would be highly advisable to computer model the original & the aluminum design, then do an FEA of each to compare them

a steel on on the other hand, just build the damn thing. people have been building chassis for vehicles out of steel tubing for a century and then destroying said vehicles an redic speeds without ever doing a bit of "proper design work" the planet hasnt exploded yet

DOM tubing > stamped & welded assemblies

 

[shooff82]

My thoughts exactly. It might be an ambitiuos project, but very possible. And yes, I have thoght about turning it 90. I have a 3.4 I thought about using, but mating to a rwd trans is the trick. The auto and 5speed out of the lincoln ls V8 is supposed to have the same bell housing. Good luck finding one laying around. Or maybe a 4cam mod motor....

 

[32MTX]

mod motors have different bellhousing patterns

I don't see any benefit of a tubular subframe on a SHO, based on where it has to bolt to, what all bolts to it, you aren't going to cut down a lot of metal........ in fact, it could be HEAVIER

now what would be cool is to make some kind of tube chassis you could put a SHO body onto........ RWD of course

connect the drivetrain and suspension to it and viola....... could be pretty interesting

 

[firebat45]

I've thought about it before. I can almost guarantee it will be stronger and lighter if you do it right. Worth the cost? Probably not, unless you do it yourself, and enjoy fabricating.

Of course, making an exact stock replacement is dumb. If I were to make a tubular subframe, I'd make some tubular LCAs and custom motor/tranny mounts to go with it. There would be some serious weight loss and stiffness increase then.

 

[shooff82]

I know. I meant as a different drivetrain choice. I intend to make it a rwd sometime. I thought about using the underpinnings from an MN12 tbird or cougar. That way I could still use my slicer wheels and have IRS. I think it would be more stealthy that way and those cars are dirt cheap. It would be A LOT easier to buy a midsize rwd sedan, but it wouldn't be an SHO would it?

 

[shooff82]

I've thought about it before. I can almost guarantee it will be stronger and lighter if you do it right. Worth the cost? Probably not, unless you do it yourself, and enjoy fabricating.

Of course, making an exact stock replacement is dumb. If I were to make a tubular subframe, I'd make some tubular LCAs and custom motor/tranny mounts to go with it. There would be some serious weight loss and stiffness increase then.

Precisely

 

[firebat45]

Funny that you'd mention that. I'm in the middle of making mine RWD and someone else already has, we both used MN12 rear subframes.

 

[shooff82]

Are you going to turn the intake around or cut holes in the firewall? Or are you going to tunnel it out and tuck the motor back in a tasteful manner? I want to use a 3.4, but the trans fitment and with the waterpump being on the back of the engine are making me second guess it. Are you using the bird front subframe too?

 

[firebat45]

Intake flipped, no holes in the firewall for me. The motor fits without a huge tunnel, and keeping a stock interior/dashboard (beside the driveshaft tunnel of course) was a priority for me. If you want to use the 3.4, go for it. Don't let silly things stop you. There's always electric water pumps. and custom trannies.

Not using MN12 front, if I'm going to all this work I want something with more aftermarket options. I'm using Mustang II spindles, and my own design crossmember/subframe/arms,

 

[shooff82]

That's awesome! I'm going to keep my interior stock too. I've wondered about inline waterpumps too, but most people say "for racing use only". I guess they're not intended for daily street use, which is what my car is going to be. Maybe occasional track use, but their aren't any clubs or autox tracks where I live. Did you luck out and get a bird with rear discs? I was wondering about a cobra IRS, but they're made for cars with 4link rears. Didn't know if it would work without extensive fabricating.

 

[sperold]

A tubular or HSS frame would be a great way to save a SHO that otherwise would be headed to the crusher. It would be a lot of work, and some of it would be upside down under the car, but lets face it..... it wouldn't be any more work than putting the SHO driveline and wiring harnesses in another model of Taurus or another different car.