Tightening up a coupe with convertible parts?

[wildbill59]

Are there any pieces from a convertible f-body that can be used to tighten up a coupe? I remember, back in the 60s, factory race cars - like 63 Z-11 Impalas - sometimes used x-members from convertibles to stiffen up the coupe frames. When I've looked up subframe connecters and such, I often see in the description 'except convertible'. There's obviously some difference, any factory parts like x-members, crossmembers, subframe connectors, etc. that would bolt onto my 93 coupe?

[2.8 Bird]

Re: Tightening up a coupe with convertible parts?

There are subframes you can buy.

http://www.jegs.com/p/UMI-Performanc...71012/10002/-1

[wildbill59]

Re: Tightening up a coupe with convertible parts?

Thanks 2.8 bird for the link. Yep, I'm familiar - I spend lots of happy bathroom time reading my Summit and Jegs catalogs. The reason I was asking - I was at my local u-pull-it junkyard (trips to the junkyard always make me happy in pants! :D ), they have a 95 convertible there. If I can get a factory piece that bolts in as opposed to a 500 dollar piece that welds in... I'm sure I'll be going the strut brace/subframe connectors route eventually, but while there's a convertible available, just thought I'd see if there's anything I could use.

[fbodyrs96]

Re: Tightening up a coupe with convertible parts?

The whole bottom of the convertible is different, there's is no part that just unbolts. That's why the coupe and vert sfc's are different part number's.
Bottom of my vert

[FirebirdGT]

Re: Tightening up a coupe with convertible parts?

Are there any pieces from a convertible f-body that can be used to tighten up a coupe?

Yes - and they are in my garage right now.

1) the K-member is reinforced

2) the trans mount cross-member and tunnel brace

[fbodyrs96]

Re: Tightening up a coupe with convertible parts?

what car did that second brace come off of? mine doesn't have it. an whats the differences in the k member, never really noticed them.

[FirebirdGT]

Re: Tightening up a coupe with convertible parts?

what car did that second brace come off of? mine doesn't have it. an whats the differences in the k member, never really noticed them.

Yes, you are missing the tunnel brace. Comes on ALL models. The conv however has the X-brace also, which bolts to the trans cross member.

The conv K-member has internal bracing, and the external bracing rods.
.

[fbodyrs96]

Re: Tightening up a coupe with convertible parts?

I've seen a lot with and without the tunnel brace, but I've never seen the x brace before.

[wildbill59]

Re: Tightening up a coupe with convertible parts?

Now that's what I'm talkin' about. Thanks, FirebirdGT - lovin' that tunnel brace! I'll be off to the junkyard today. A couple of quick questions: 1st, My car is a 5-speed, should that tunnel brace mount to a manual crossmember, or could I even use the auto piece with a manual trans mount? And second, that k-member - is it just reinforced with those two rods, or is the whole k-member beefier? Thanks again, this is exactly the info I was looking for!

[wildbill59]

Re: Tightening up a coupe with convertible parts?

Sorry, just re-read your post, I see you stated that the k-member is both internally and externally braced.

[FirebirdGT]

Re: Tightening up a coupe with convertible parts?

Now that's what I'm talkin' about. Thanks, FirebirdGT - lovin' that tunnel brace! I'll be off to the junkyard today. A couple of quick questions: 1st, My car is a 5-speed, should that tunnel brace mount to a manual crossmember, or could I even use the auto piece with a manual trans mount? And second, that k-member - is it just reinforced with those two rods, or is the whole k-member beefier? Thanks again, this is exactly the info I was looking for!

Since you have a 93, you can replace the crappy V6 trans mount and use the LT1 auto trans member and install a T56 (or 1LE if you can find one) trans mount.
.

[wildbill59]

Re: Tightening up a coupe with convertible parts?

Excellent, thanks! Tell me, will all f-body convertibles have this setup, or just Z/28 and 1LE cars? The car at my junkyard is a V6/auto (didn't get a chance to get to check it out today), I'm really hopin' it has that crossmember/x-member like the one in your garage!

[FirebirdGT]

Re: Tightening up a coupe with convertible parts?

Excellent, thanks! Tell me, will all f-body convertibles have this setup, or just Z/28 and 1LE cars? The car at my junkyard is a V6/auto (didn't get a chance to get to check it out today), I'm really hopin' it has that crossmember/x-member like the one in your garage!

All conv came from the factory with the X-brace and special trans mount brace for it to attach to. The trans mount cross-member is different for auto vs 5-speed vs 6-speed (and are different for 98+ cars vs 93-97)
.

[wildbill59]

Re: Tightening up a coupe with convertible parts?

Good deal. I'm going try to get to the yard today or Friday, I'll take some pics. Thanks again for the info!