Tranny tunnel cage?

Three Peaks · #1 (**permalink**) 11-27-2006, 06:06 PM

On the original style frames, have any of you added a tranny tunnel cage for extra stiffening like the Factory Five style support?

I was thinking (always a dangerous thing) that I could make the tranny support cross brace removable by cutting it about a 1/2" from the rails and putting matching bolted plates on each end so it can be removed and replaced when removing the tranny. However,I'm afraid it would weaken the chassis to remove a piece at that point, hence wanting to add some stiffening to the chassis. Also thought it might add some stiffening for road racing applications.

What would be the downside to doing this? I admit I haven't gotten past the "what if" stage of this idea yet, but it sounds do-able and won't substantially alter the appearance or the car.

Throw your 2 cent's worth in here guys!

Bob

Rick Parker · #2 (**permalink**) 11-27-2006, 07:17 PM

Bob:

This was something that was done on the original Daytona Coupes. When Shelby decided to do the 289 continuation cars, specifically the FIA variants it was included. It adds a lot of triangulation in several planes and will prevent twisting and "Porpising" or longitudinal flexing. All the suspension pickup points would need to be located and plumbed for accuracy, since once this is done there will not be ANY flexing of the chassis.

fasterpatrick · #3 (**permalink**) 11-28-2006, 08:08 PM

Yes, extra bracing is always a good idea. I plan on taking it a step further by making it posible to remove the entire trany tunnel suport and remove the tranny right out through the cockpit. this should make for some interesting fabrication. Stay tunned, Patrick

fastraxsg · #4 (**permalink**) 11-30-2006, 05:43 AM

Patrick,
wouldn't that involve removing the dash, wiring, seats, drive shaft safety hoops, carpets (assuming you have them) and shifter surround and other misc. bits? You still need to crawl under to drop the u-joints and the bolts that fasten the lot together? If it is a top loader then its worth it as you probably won't have to drop it. Seems like a lot of work as opposed to dropping it out the bottom.

Bob, what about bolt in safety hoops instead of a tunnel?
Ken

Three Peaks · #5 (**permalink**) 11-30-2006, 08:11 AM

Ken,
I'm not looking for a safety loop for the driveline. I'm looking to stiffen the chassis as per the Factory Five style tranny tunnel cage. I will be adding a safety hoop also but that is a separate issue.
From what I've heard, this can add substantial stiffness and torsional rigidity to the chassis so I can remove the crossmember to make a removable tranny mount without losing the chassis stiffness I would like to have for track events.

Still a thought at this point and not a certainty but just wanted to get some input since once I start on this it is a weld in proposition and not easily removed.

Bob

kris-kincaid · #6 (**permalink**) 11-30-2006, 03:50 PM

Here's what Shelby does on the 7000 cars

It would be easy to do it on a 427, but why bother? Unless you are running your car professionally in SCCA competition, you shouldn't need it.

fasterpatrick · #7 (**permalink**) 11-30-2006, 07:26 PM

Fastraxsg,
Not in my rules, maybe just one panel on the dash. Think engine hoist back wards, remember I play by nobodies rules. Besides the trans will not fit between the frame so dropping it will not work. this will be one solid structure tunnel, hoops, floor and yes carpet. A few, 8-12 well placed bolts and the whole works will lift right off for access to the trans. The fun part was bending the hoop at the fire wall so the bellhouseing will fit through. Don't worry will post lots of pics when the time comes. Patrick

P.S. I refer to it as a backbone and yes to having it.

fastraxsg · #8 (**permalink**) 11-30-2006, 10:15 PM

Patrick,
Its always nice to see someone thinking outside the chassis limits, this should be a very interesting solution for others to consider. I'll look forward to the advanced stages and the photos.

Bob, Something different.....I attached some naked chassis pictures of a UK Python with a rail system that goes front to back with cross bracing near the trans. The Chassis is built in Sri Lanka and is of a UK design. There has been heaps of criticism of the chassis but not of this part. I will have larger images in my gallery today.
Ken

Three Peaks · #9 (**permalink**) 12-01-2006, 08:01 AM

Ken,
That is very close to the backbone I was proposing to build. Once you have the pics in your gallery I will look them over in a larger size and down load them for reference once I get started on this part.

Thanks,
Bob

cruzer5531 · #10 (**permalink**) 12-25-2006, 02:44 PM

Bob,
You once mentioned that you had a part number for a rack and pinion from Auto Zone? I'm ready for a rack and could use the number.
My build is coming along. Engine, drive line, and framework done. I'll post a picture.
Thanks, Vic

Three Peaks · #11 (**permalink**) 12-25-2006, 06:47 PM

Vic,
Looked everywhere and and can't find the number. Since I went a different route with a Flaming River MG/Cobra rack, I didn't keep track of the unit number in the end.
You should be able to pick up a Mustang manual rack from 83-95 from Autozone for around $120 or so and it should be the same rack. I believe the manufacturer was AGR or AGS or something like that. Very nice racks for a very good price. However, last I heard they went under. But Autozone still have a pretty good stock of their racks available at last check about 8 months ago?
Let me know how you come out. Any new pics of your progress? Looking forward to see how you're doing.

Bob

cruzer5531 · #12 (**permalink**) 12-26-2006, 09:09 AM

Thanks Bob,
I found a Mustang II rack on E-Bay. should have it soon. I tried to post some photos but had no luck. I tried to compress the files but still failed. If I can't get it to work, I'll E-Mail you some. I'm now on the hunt for a windshield.
Where did you get yours? Been following your build and Patrick's. He's really come a long way fast.
Vic

Three Peaks · #13 (**permalink**) 12-26-2006, 09:59 AM

Vic,
I found my windshield on one of the forums in the classified section. Now I need to replace the glass- don't ask me how I screwed it up....

Have you tried downloading pictures to your gallery? Just go to your gallery in your profile and follow the directions. It's pretty easy- heck, even I figured it out.

Bob

cruzer5531 · #14 (**permalink**) 12-26-2006, 12:40 PM

Bob,
Photos posted. Finally figured out how to compress a photo.
I have been looking at Shell Valley cobra parts. $600+ for complete windshield.
Your build is looking great. I found a dash and steering wheel on FFR forum but the guy never would ship so I keep looking. after the frame is painted the 351w goes back in. can't wait to fire it up. Made a custom cam for it from Chet Hurbert Cams. I did a lot of research on cam design and had some imput in the grinding. You know how that goes. A little knowledge could get me in trouble.
Vic

Ant · #15 (**permalink**) 12-29-2006, 02:01 PM

Unfortunately I am unable to compress photos down enough with my present (10years Mac computer) so I cant post picts of my chassis, but someone may have some of the UK, Reynard designed backbone chassis, RamSC?

Kris has mentioned the csx 7000 series, having the tunnel bracing, this is a good move if you want a stiffer chassis, and the original designed chassis is not stiff enough for serious racing, having race two Cobras, they are hard to tune when using sticky tyres, but no doubt in their day were better than a lot of cars!!!! The problem with adding this uppper structure is having it so it ties in with the front suspension towers and the rear suspension pickup point, it basicaly has to go around the engine head area with diagonal bracing, and in the rear attach to a frame to locate springs etc, so instead of adding to an original style chassis, I went out and purchased a good chassis, as it becomes a weight issue, with having heavy lower main tubes.

fasterpatrick · #16 (**permalink**) 01-07-2007, 08:38 PM

I was still able to get my removable backbone finished and in the car. 12 bolts, tight fit, told ya I could it. I don't think I need to worry about another cross member with that cage bolted to the frame. Kind of ties the rear suspension together also should cut down on twist as well.

Patrick

There are lots of new pics in my gallery.

fastraxsg · #17 (**permalink**) 01-07-2007, 09:55 PM

Still looking slick, so when you get done, are you going to patent the design and go into business selling the plans and retire on the edge of some sunny race track with a bass fishing lake in the middle and a huge do it yourself ware house over the hills? This is amazing and I think a lot of us are wishing you lived next door....

Can't wait to see the project on the road for the first time. Better get a good video camera and practice...
Ken