So i decided to now go with 2x1" tubing for the inners and centers. I will have to pick some more steel up this week. I also completely changed the center tube design. My dad had a great idea and i ran with it. It looks great on paper and at the top of the thread in MS paint. but under the car is a different story once you see how the steels going to be ran, there's to much angle in the center tubes. i will post pics later after im done building the inner tubes.

id just go with the 2X1 tubing, you have plenty of strength in the square tubing. if its not enough, then just get 11 gauge 2X1 tubing instead of the 14 gauge 2X1.5 that would make up for toughness id reckon.

okay maybe not lol. looks like i was a minute to late ha.

When I built mine I knew that they were going to tie into the full roll cage so I did not go across the car like you are planning. I used 2X3" box and needed the ground clearance so I stuffed them up nice and tight.

Here is how they tie into the cage through the floor....

Very nice!

So i started making new rear brakets. 3rd times the charm i guess. these very close to the previous ones i had made.

I started on the rear of the inner tubes frist. the chop saw could only cut 45° but i was still abile to cut what i needed by take some peaces off the saw and by eye balling the cut.

I held them in place and used a angle finder to mark where i was going to cut. i had an idea of how close i wanted to run the tubes to the floor boards too.

Then i started to mark and cut tubes for the drivers side since it looked easier. i like to knock the easy stuff out first.

.

I put the diver side inner subframe up into place to see if i needed to make any other improvements and to see if i was going to have enough room for only a pencil to fit in between the floor boards and sub frames. i made my goal

Next i start on the passenger side. i followed the contours the best i could with square tubing and they turned out great.

Here they are done. i still have a few things to tweak.

i used 16ft of tubing to make both and still had some small scrap left over

Heres some shots of them under the car but not tacked to the front and rear plates yet.
I used the drain hole pulgs as a gide along with some other things and make sure both were identicaly ran other then the bends up and down bends i had to make.

Now those are different!! In a good way!!

they look like alston SFC's, but square! Cool deal, but is all the extra weight worth it?

he used thinner 14 ga metal vs 11 gauge for that reason.
besides, at most we are talking about 30# over a comparable store bought sfc design that is much less stiff.
besides that... the weight is below the GC of the car, so it helps to bring the CG down, which is good.

all in all, id say that it was worth it

looks good. dont the welded points create weak points? i always thought using once peice of tubing is stronger than something of smaller peices welded together. still tho they look good. nice job

can u post pics of that diff cover? lol u look like u did alil reinforcing to that stock steel one. at first i thought it was an aluminum support girdle but its clearly not.

keep up the good work! did u end up boxing the perimeter SFC? or just leaving it hollow?

Thanks.
yea i reinforced mine. its definitely not like the ones that incorporate the mains. but if anything it will add some rigidity to the housing .

Anyway back to the subframes.

The
14ga 2x1" rectangular tubing is 1.600 Weight per lineal foor
There was 94" of tubing used to make both inner subframes.
= 12.53 lbs total weight

The
14ga 2.25" rectangular tubing is 1.882 Weight per lineal foor
There was 124" of tubing used to make both outter subframes.
= 19.45 total weight

(combined total weight so far 31.98 lbs)


Here is how they look under the car now.


I plan to tie both inner and outer sub frames together like this.

Did you make a wooden buck after finishing them, before installing them, so that you could duplicate & sell some more?

you know, fueled soul, you could go into business with this.
i had (and still have) a friend that makes custom longboard skateboards.
he sold mostly to guys on campus and had a sweet little side job going.
when he graduated last semester, he got a small business license, and is working on a patent for a downhill truck design.
he never thought that his little hobby would blossom into a business, but it has...
the point of all this is...
dont sell yourself short.
you clearly have some fabrication talent and creativity.
there is a definite niche for thirdgen camaro parts that are affordable and well thought out.
if you were to sell your subframe connectors, i'd probably buy a pair, and if they were affordably priced (less than $225) id buy them for sure.

you should think about it.

still not done with them yet

Thanks!
your compliments are very much appreciated. i have thought about it but id really have to think about it some more. But before i started putting this together and building it i kinda already knew that there was possibility people would be interested in my designed subframes. I could reproduce them, id ovisously make them better and improve upon somethings. . .
Its a real possibility and all think about it more.

one thing i would consider is the strength of the "curved" piece you made.
other than that, you have a really good design

Make sure you weld all those joints up as well. They might not need it for strength, but it serves the same purpose of keeping moisture out between the tubes. We've all taken a bracket off of a car frame or something and seen the rust that's accumulated behind it.

Looks good. Always happy to see someone just go buy some material and figure it out instead of always posting the same silly questions over and over again. I haven't been posting here much lately again because it's always the same stuff over and over again.

Good job.

Gonna coat'm with bedliner when you're done? I'm not following your design just yet until I see some more of it. From the pictures it kind've looks like you are building them to be bolted in place?

EDIT: After looking at the pics again looks like I'm seeing it wrong. The bolts I saw were for your rear suspension. Is that the stock setup or did you go with something else?

Mathius

I re-worked that area tonight for mine own set. like i said if i where to build a set for others id improve upon somethings.

the curved piece with the bolts attaches to the rear LCA mounts so that the subframe can be bolted up for easy welding and extra strength at the joint.
unless thats not what you were talking about

Deffanatly what i plan on doing

Yea, i agree with you

Thanks!

Im probably going to powder coat them.
I built them to swing into place from the rear LCA's. i can take them off and put them back on so everything fits like it was once the inners and outers are tied together with the center tubes. then i can take them off and fully weld each place then bolt them back in and swing them into place so nothing will shift or move im using the rear LCA bolts as a gide for fitment for the intire subframes. just makes it simple, i planned it like that from the beginning

?

i was talking about something else

sorry, not you, matius
i guess thats what the quote button is for lol

I built them to swing into place from the rear LCA's. i can take them off and put them back on so everything fits like it was once the inners and outers are tied together with the center tubes. then i can take them off and fully weld each place then bolt them back in and swing them into place so nothing will shift or move im using the rear LCA bolts as a gide for fitment for the intire subframes. just makes it simple, i planned it like that from the beginning

awesome job. Someone gave me a set of alston sfc's but i still havent decided what kind i want for the perimeter sfc's. I can't wait to see how they tie in. Great job. I envy your skills.

So i re-worked the passenger inner sub frame a bit. I wanted to tuck it up tighter and have it match the drivers side floor board to sub frame gap.

So i finally got around to the the outer sub frames again, i had to notch and modifie them so they would touch the front sub frames 360°. Why? . . . well because now these sit 100% flush and can be welded 360° I have built ever peace this way. I believe 360° of weld around the factory sub frames are better then wimpy lines of welds.

I have to prep a few areas, but I'm almost ready to tack down the inner and outer sub frames and start on the center tubes!!!


Passenger side

Drivers side. i need to clean both the left and right sides up but i will do that after the center tubes are done and the sub frames are off the car

Cutting across them was no doubt the easy part...But how did you make the lengthwise cuts? Bandsaw?

You gonna make notches at each point along them, as the floor drops to keep them touching 110%?

I wish i had a band saw! i wish i had a lot of other tools too!
You mean the notches i made? I used a cut off wheel. oh, no not the floor boards just the ends of the sub frame connectors to the factory frame rails them self. sorry if that was confusing

I got started on the center tubes last week. i pretty much wrap them up tonight.

Cardboard worked great for mocking up the angles.

last set of tubes to be tacked on!

Here they are! i will double check my work tomorrow before i cut the tacks off the factory frame rails and i will take some better pics of them off the car.

Here they are off the car.
Looking at them from the top.

Looking at the from the bottem.

Both sides weigh the same and are built close to identical as possible.