LT1Brutus

I read an article in an import mag (yes just shoot me now) the other day regarding one of those Factory modified cars (think it was Nissan Motorsports or MazdaSpeed). IN it, they said that one of the things they do to the "type R" cars is that they go back and finish weld a lot of areas where the normal cars are just tack welded. They claim that this significantly changes the chassis ridgidity to the extent that the magazine is now suggesting that readers would notice significant cornering differences by going through the trouble of doing this.
I then read a post on a Mustang board where a couple autoX'ers and one drag racer Also claimed amazing chassis improvements.
Immediately afterwards I went out to the Z and started looking underneath the car as well as under the carpet in the rear hatch area, and under the hood. I see A LOT of tack welds. Is there room for improvement that is worth the added weight from the welds?? Has anyone done this? I'd like to do Sub-frame connectors but don't have the $$$. ON the other hand, I do have acces to a welder, can weld good, and have some POR-15 to keep the new welded areas from corroding.
Comments PLEASE!!

rasilverbird

I can't imagine that it would benefit that much. Remember, when the ricers do mods, they're fighting for every last drop of performance they can get...they'll spend $300 for 2 hp. I've never heard of anyone re-welding an f-body up for added support. I can see how it would help, but the trouble of going through the whole car, sanding, welding, grinding, painting, all while trying not to burn any carpet or fuel lines just doesn't sound like time well spent to me.

chevyguy3

ive had some of the tack welds rip apart on my car before. also put 7 cracks in the floorpan.... i didnt bother welding everything up, just re-welded where the tack welds broke and fixed the cracks. i now have a TA that mounts to the subframes to fix the problem

dougg01

There is a well-known autocrosser from Iowa that does this to the cars he builds. He currently (last I checked) was running an orange 2nd-gen in CP and typically is one of the top 5 inthe country. He seems to think it makes a huge difference in chassis shift and worth the time-effort.

When I used to live out that way and see the car run....when the inside front tire is lifting 3-4 inches off the ground in the corners.....I believe what the guy tells me about chassis stiffness.

I think he put his car (completely stripped) on a rotisserie to do all the seams.

LT1Brutus

Hmmm...sounds to me like this hasn't been widely tried. I have to say that I think it would make a huge difference but I was looking for a little conformation.
Particularly, there are some pretty dinky welds in the strut-tower and front subframe area. I think a little carefull welding in these area would tighten up the cowl and what not.
WTF, I think that when I eventually paint my car, I'm going to do it, though, I won't be able to swear by it since at that time I'll probably be putting in a street cage, SFCs, tubular K-member, and doing some serious sound deadening for another "expirament" that I'm toying w/. Basically, I want by car to be porsche stiff and lexus quiet......without adding more than 125lbs and without significantly confining interior use. I'll probably be custom fabbing a roll cage so that it fits super tight...as in the interior panels will be trimmed to fit around it including the door sill plastic, the rear speaker area and especially the headliner. I'll also be adding a custom fabbed crossbrace that sits just above the upper dash the ties the A-pillars together. That piece will likely be boxed aluminum.