Before I say which side of the boat I'm on, I first wanted to see if first - have any of you done this, and second what are your opinions or thoughts on this?



If you have no clue what I'm asking about, thats fine - I'm just looking for anybody who has done this on an FC (I know people who have done this on MX-5s which has spawned a debate, lol)

Why are you seam welding?

Does the appropriate sanctioning body allow it?



Its a PAIN IN THE ASS



How are you going to ensure you dont "tweak" the unibody?





Most Seam welding was done in "spec" car BIG $$$$ Series with factory support after the chassis was acid dipped to reduce the weight

Just get a tube chassis, I guess you've noticed how weak these cars are lol...

There are ways to ensure you don't tweak the unibody - it actually hasn't happened on the MX-5s that were done (possibly because there is less there, dunno)



I didnt say I was actually going to do it, but the sanctioning body allows this modification in an open class - so I'm looking into it. I wont be able to acid dip as I'm too far along to go back now unless I enjoy smoking cubans I lit w/ $100 bills, lol..



I'm on the fence in the debate which is why i was curious if anybody has done it... I was thinking of at least doing the front clip since it seems to be the weakest area. I could add bracing to the floor behind the drivers seat as well. That in conjunction with the 8pt cage and door bars should be plenty strong.



Keep the questions/comments coming though.. I'm curious...

Unfortunately, yes. lol...

Dont want to go tube chassis - i would just like a "happy medium" between a full body and a tube...

One of the MAJOR hurdles is getting the seam sealer out of the seam BEFORE welding

No kidding... I've had my time with that crap.



My biggest hurdle is getting it setup on a frame jig... My uncle thinks I can do the front clip just fine without having the car setup on a jig...



However, I cant do the firewall since it's already painted, but I mainly wanted to focus on the inner fenders, strut mount area, door and rockers... the rest will be fine IMHO...

IMHO: Do it all or do NOTHING!



Why? Now you are transfering more load elsewhere

we used to bend our camber plates, theres a lot of forces at the strut towers!

That was my main objective - the strut areas and the front clip -- since i cant really get it on a jig or strip it completely down (just dont have the resources) i would like to reinforce the weak areas...



I'm a little way out from doing this, but i'll have to take some pics, and do a little writeup I guess. I've got an MX5 buddy that does this all the time, so I'll use him as an aid...

If you are not able to seam weld certain areas, you may use rivets, as they will also do the job.



you can use them evnely spaced acrross a one of the panels and it will give a similar effect as the seam weldng. Especially if you only want to do thi to the front strut tower area.

I did it on the RX-7 and the RX-8 for Falken. The car is very rigid now. You can lift one corner and 3 wheels come off the ground just after suspension sags about an inch or so. Both are drift cars. One thing to note, when they crash it's a lot harder to repair the damage since essentially the car is one piece now. On both cars, we stripped down the paint and most of the seam sealer out, then i used a map torch to burn off the rest of the sealer, and a wire brush to get it off after burning. Takes forever. I think about a week prepping the RX-8 alone. The RX-7 wasn't completely seam welded though since we didn't have the time, so we just did the front strut areas and the engine bay along with the rear hatch section down to just behind the front seats.



Rivets also work well.

Thanks guys - I'm liking the rivet idea - but will probably still do the welding..



Like speedmachine on the FC, i just plan to do the front strut areas and the rear hatch, etc... My engine bay has already been repainted and I'm not willing to mess up the paint.



I'll see what I can do.. I think that even doing the front end and rear hatch areas would be better than nothing at all. Probably look into the foam filler too...

another thing to think about is how much heat you're putting into any area at one time. You could be making the frame a lot more brittle if you do continuous seams. It may be better (with less chance of tweaking the frame) to stitch-weld it. If you really want it seamed afterwards, you can wait for the area to cool down and go in to get the rest of it afterwards.