jaa1992

Need some specific pictures of any mounting plates and gussets required to mount the main hoop and the rearward supports.
Do I need a forward support? Where can it go so the passenger seat can still be used?

Main hoop design is not and issue. What about rearward supports? Just straight back or a different design.

Can't go a full cage yet - gets too many street miles and a cage is "unsafe" on the street.

drivinhard

check on the NASA CCR on cage specs, dunno what your car's base weight is for TT/PT, but NASA is .120" wall on tubing for 3k lbs over, minus fuel/driver. just FYI...

Shrek

I did an Autopower install in my 89 autocrosser about 7 years ago. Plates were welded to frame then 3 high grade fasteners per plate were used.

urtoslo

Go with an Autopower bar. We installed a bunch of those years ago, an easy straight forward procedure. Those bars have rear supports only and don't need front support. Any cage fabricator can install it for you too. The bar in mine, that had front/side bars, was custom made by Mitch Piper.

jaa1992

Thanks for the pictures Shrek!
Did you have any extra support under the mounting plates, they look like they overhang from the frame a bit. Just wondering.

Yes, I could buy and autopower and have some one put it in.
The object of this is the first half of a cage and it will meet the NASA CCR for tubing specs. Have a local shop doing the fabrication - sorta like the Georgia version of Mitch Piper. He just finished a few c5 cages and now its my turn.

Shrek

about 2/3 overlap of the frame, and It left just enough clearance for the fasteners to clear. you have the option to bolt or weld and I chose to bolt it because I was using it mainly as a harness bar/stiffener. I had plans to eventually track the car and then I would have went back in to weld it 100% plate to plate. Not sure about my logic at the time, but later on I felt I should have just welded it and been done with it.

ZR1 MK

In case you plan on adding to the roll bar for a full cage in the future, you need a bar that will meet the rules. Some bars are 1 3/4" x .095", but most rules require 1 3/4" x .120 or 2" x .095 for the Corvette.

jaa1992

Yep, I'll be following the CCR's for tube size and thickness. It only makes sense.

So question - the mounting plate like Shrek's pictures show. Everything will be welded to the frame. With 1/3 of the mounting plate hanging over the frame rail should the over hang be gusseted to the frame to avoid deformation of the plate in a rollover? If so 1, 2 or 3.

I need to be able to show this to the CEO and say "See, if I roll over the bar will not punch through." Also need to be able to explain to the fabricator if they are needed.

Shrek

If you're welding it in, I would cut off all the extra flange plate around the tubes, then weld it directly to the frame 100% around. The tubing is positioned completely over the frame rail with nothing hanging over.

jaa1992

Perfect, thats what I was wondering.

ZR1 MK

From memory, as I put my bar in approx 14 years ago, I remember the flanges centered on the frame, not as pictured above. No extra plates and just welded direct to the frame. All around the perimeter and the holes too.

pablocruise

I put a piece of plate on the bar and welded it on. Then, welded to the frame.
(I am just a garage hack)

grantar2

Of course mine is a street car which will experience track fantasies and autox, but I can even imagine tearing my interior up like that. Now if it's pure race.

pablocruise

:o I forgot to mention that it is a track only car :o

opel

You can also try www.swracecars.com they seem to have good prices.I installed mine just this past fall, It's a 1 3/4" DOM .120 wall. This is the post from August when I did mine. http://forums.corvetteforum.com/c4-p...4-rollbar.html
Dave

jaa1992

I finally found a local fabricator that will be doing the fabrication and install (he just completed a few c5 NASA spec cages).
I've had a few PM's from other fabricators and I just can't be without the car for very long. They are jus too far away.
I was able to arrange to drop it off Tues and pick it up Friday. He is less than an hour from home so the wife can pick me up and take me back on Fri. Had to arrange work from home so it all works.

Carolina C4 Racer

Hey James,
Tell me more about the local guy. Is it the guy I told you about app. 1 year ago? Give me some details & price info.

Anthony

pablocruise

These pics were emailed to me by S&W a few years back...









I ordered this kit in mild steel, and paid too much for the shipping to SoCal.

Not sure if the kit has since been changed. I still have the it, collecting spiderwebs in a corner of the storage locker.

myles930

Is that a full cage setup? If so, would you mind posting more pics please? I am building a C4 for the mile and I am trying to get ideas for the cage.

Thanks

ScaryFast

FYI, although I'm a little late to this thread, but we got NASA to approve the main hoop welding to the ledge behind the seats instead of running down to the floor (like in pablocruise's photo). You just need the plates welded there at the hump per the CCR spec.

If your build is not complete and you'd like to see pics, let me know. I can post them later but I don't have them on this particular computer...