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Silver69Camaro
11-08-2005, 01:47 PM
I'm trying to get an idea of how many of you would be interested in a full frame for unibody cars. Here's the chassis:
http://hotrod.com/featuredvehicles/113_0507_muscle07_z.jpg

This chassis has been extremely sucessful with builders like Bobby Alloway, Foose, etc. You can get C5 or our in-house front suspension, and a multitude of rear setups (air, triangulated 4-bar, parallel 4-bar, 4-link, etc). This is a very rigid chassis both in bending and in torsion. 1.0+g in cornering? No problem. YOU pick the ride height. YOU choose the suspension configuration.

But for us Camaro guys, we have to modify the car. After hours and hours, I've found there is no feasable way to create a bolt-on chassis for the Camaro like we did for the '55-'57 Chev and the C1 Vette. Currently, builders have to remove the floor and most of the trunk. But, if there is enough interest, we can solve that problem to make installing this chassis simple enough for most gearheads.

So guys, tell me. How much work would you be willing to do to install a new chassis?
__________________
Matt Jones
Mechanical Engineer
Art Morrison Enterprises

TravisB
11-08-2005, 02:13 PM
Most of the time factory floor pans don't allow enough room for a chassis and exhaust etc etc

We would have no problem cutting anything needed out of the way..... :thumbsup:

XcYZ
11-08-2005, 02:36 PM
Definitely intersting to me, something I may have considered before starting my project.

Is that the Max-g chassis?

Silver69Camaro
11-08-2005, 02:39 PM
Definitely intersting to me, something I may have considered before starting my project.

Is that the Max-g chassis?

Yep, it is. We're trying to get an idea on how to make this chassis more appealing to those who don't want to modify the floor a whole lot. On the other hand, they're selling like crazy.

XcYZ
11-08-2005, 03:01 PM
You wouldn't happen to have any build pictures from any of your customers, would you? I'd really like to see it going in a car and how much of the firewall was cut.

Hooligan
11-08-2005, 03:16 PM
I'm planning on using one for my roadrunner. Ill cut out anything I have to, that being said the less I have to fab up the better. ;)

Mkelcy
11-08-2005, 04:54 PM
I'd like to see one built. I'm not so concerned about taking out the floor, but how it goes back together. For example, the "X" bracing in the frame goes right where the seats are located. Can you get seats in and still have adequate headroom? I love the idea of a full framed car, but want some idea what I'm getting into and what I'll have when I'm done.

Nutsy
11-08-2005, 06:59 PM
I am very interested in this. I am located really close to you guys too if you are looking for a Mule car!

Trevor

Hooligan
11-08-2005, 07:04 PM
Nutsy I think your on to something...

I'm not located anywhere near ArtMorrison but I'll ship my car to them if they want to use it for a mule.

Silver69Camaro
11-09-2005, 09:56 AM
Thanks for the comments guys, keep them coming.

Mkelcy,
It's difficult to answer your question because it depends on what kind of seats you are installing and how tall you are. In Camaros, for example, the pan in which the seat bolts on to would be about the same height as it would be with the new chassis (of course, you can place the chassis anywhere you want), so stock seats could probably be used.
For a more in-depth version of what kind of work will need to be done, feel free to call one of our sales guys. They know these products like none other, and have personal experience with this stuff....no pressure, you don't need to buy anything to make them talk.

TravisB
11-09-2005, 10:05 AM
For a more in-depth version of what kind of work will need to be done, feel free to call one of our sales guys. They know these products like none other, and have personal experience with this stuff....no pressure, you don't need to buy anything to make them talk.


I tried to talk to one of the sales guys one time about a bubble top project and he was helpful until I told him that I wanted it to call me back left him 2 or 3 messages and no return call, I finally got a hold of Craig over at pt.com but we had already found another guy to build one......If I ever deal with morrison again I guess I will have to do it in person! I do think the Frame is a nice piece and would have loved to have had one.

Silver69Camaro
11-09-2005, 11:27 AM
I apoligize for that, I'm sure next time will be a better experience.

MarkM66
11-09-2005, 01:52 PM
Not sure I see a reason for a full frame in a Camaro/Nova.

My first thought was increased ground clearance if you dropped the body into the frame, but you'd still have the exhaust down there. Unless you moved the entire floor up with the frame. But that wouldnt work to well for head clearances.

I can also see that having a full frame would make it easier to install a rear suspension of choice.

Other then that, what advantages would a full frame have?

TravisB
11-09-2005, 02:06 PM
I apoligize for that, I'm sure next time will be a better experience.


I know that is is not your fault..lol Craig has assured me that it would not happen again... :thumbsup: :thumbsup:

Silver69Camaro
11-09-2005, 02:21 PM
Not sure I see a reason for a full frame in a Camaro/Nova.

My first thought was increased ground clearance if you dropped the body into the frame, but you'd still have the exhaust down there. Unless you moved the entire floor up with the frame. But that wouldnt work to well for head clearances.

I can also see that having a full frame would make it easier to install a rear suspension of choice.

Other then that, what advantages would a full frame have?

Mark,
Unibodys are extremely flexible, and that is generally frowned upon. Even with subframe connectors, the chassis is still overly flexible for high-end performance. The springs should be doing the work, not the chassis. A properly designed full-frame will greatly increase strength and solve that issue.

And yes, you do gain several inches of ground clearance. In our design, the exhaust is routed THROUGH the frame, not under it. You can get an unbelievably low stance with this design, and still have it be practical on the street.

Also, head clearance to the roof is generally not an issue. On a Camaro for example, the pan in which the seat bolts to is already raised above the floor pan, so you really don't lose much (if at all) clearance. Combine that with a variety of seat brackets available, or modify your own, the problem is easily solved.

race-rodz
11-09-2005, 10:14 PM
well in the 3-link thread i talked about what a P.I.T.A. it is trying to find a structurally solid starting point in an early mustang. a rigid frame would be ideal, BUT.... (always a "but") this would be great for a "new" project.... not really ideal for somebody(like myself) trying to make a semi finished car better. its not that i mind the fab work accociated with the full frame install..... its the part where everything that works in the car now needs to be redone....like all the interior, the allready done bodywork (cut the floor out of a car and bolt it down to a rigid frame and tell me its still almost ready for paint...i think not)

like i said...i think its great for a new project. if the suspension "works" and you can fit decent wheel/tire combo under it...then i think it would sell(i personally wouldnt buy one... for the reasons stated above unless of coarse you wanted to whip one out for a 65 mustang to park in your booth at sema next year :unibrow: )

race-rodz
11-09-2005, 10:20 PM
keep in mind...along with the floor and firewall....its also wheel houses/tubs, inner fenders, mod the core support, and findig the best place(s) for the body mounts and a structure not originally intended to be bolted down at spots A,B,C etc. one could "unibody" the car into the rigid chassis, but that would take almost as much "engineering" to successfully pull off.

62fairlane
11-09-2005, 10:40 PM
I think on some cars you could "unibody" it in pretty easy. on my fairlane (I think classics mustangs are this way too) the inside of the rockers are nice flat and vertical. But I have the added bonus over them of subframe mounted trans x-member BEEFY torque boxes (talking like .090" plate) and a reall beefy front clip.

I could see this full frame really cutting into rear footwell area and the work for body mounts would prob be more than doing a unibody install. plus with a unibody install I think you would have a REAL stiff structure that would be lighter than a frame/body setup (IE no mounts to flex, no extra metal for mounts) if you had a chassis tailored for the specific car/body that could just be rolled under a gutted shell and once lined up welded in place would be easier. heck even have a couple cheap locating brackets to bolt it in place for welding.

I think the more you add to a unibody to strengthen it the better. could those outer frame rails be made not as wide so when tucked up next to and welded to a stock rocker it forms a beefy component? plus it seems with most of the hardtop cars you are just gonna be plauged with flex anyways.

Silver69Camaro
11-10-2005, 08:20 AM
62Fairlane,
The purpose of this frame, and what most builders currently do, is weld the body to the frame...no bolt-ons. Some builders even go further to use 10ga. floorpans to make it one super stiff structure. This is not intended to be bolted on, but it can be done I'm sure. However, with the shell welded to the frame, the front fenders & core support can all be bolted on as stock.

Race-rodz,
Believe it or not, we have indeed sold our display models at shows! We never intend to do that, but hey, it saves them shipping.

The suspension used in these chassis works very well, and you can put any size tire you want in there. The same suspension used in Art Morrison's GT55 (designed by Katz) can be had in this chassis...or C5 Vette components (front only). Both make a very, very nimble and well handling car. Like I said, 1.0+g is easily done.

ProdigyCustoms
11-10-2005, 11:06 AM
I think it is a great idea, look at Prodigy. The only problem I see, and I was looking for Craig to discuss this, is putting the body on top of the frame as you present design would require, will make it a 4 wheel drive stance. And there is no real way, with your present design, to channel the body. I think channeling the body is the single best move one can make, lowering the center of gravity 4 inches, and allowing the car to be dropped 3 to 4 inches, while keeping the suspension out of droop.

We would love to work with you guys adapting your chassis into a Camaro, while being able to channel the body. It would require some changes at the toe boards, but as witnessed in Prodigy and the Motion car, is very doable.

Silver69Camaro
11-10-2005, 04:25 PM
Prodigy,
I think there must be some miscommunication.

The ONLY way to install this chassis is to channel the body over the frame. The outriggers of the floor support are made to be the same width as the vehicle's pinchweld-to-pinchweld width. The floor of the vehicle is removed, right up to the pinchwelds, and the body is dropped on and new floor pans are made. So, like you said, the body is dropped 4" without any changes to the front and rear rail height. The body is NOT simply sitting on top of the frame.

As far as ride height is concerned, each frame is custom made to the customer's desires. If he wants a 10" rocker-to-ground clearance, fine. If he wants 2", no problem. He can have 2" in the front, and 5" in the rear if he wants. However, suspension is always left unchanged to maintain correct geometry.

race-rodz
11-10-2005, 04:55 PM
what does the "average" chassis tip the scales at? complete with all the suspension........ add the weight of the body shell and new int tin, how does it compare to a traditional unibody car?

obviously sacrificing "some" weight for the rigid, updated suspension.... is acceptable.... im just curious about how much.

ProdigyCustoms
11-11-2005, 07:46 AM
The problem I see is the interior flooring and seating has to be on top of the frame rails. If you channel the body on a Camaro, you will need to be 5'6" or less to sit in the car in the front seats, and worse in the rear seat.

Silver69Camaro
11-11-2005, 08:42 AM
Race-Rodz,
The average chassis weighs about 425 lbs complete less brakes and axle shafts. Bare chassis weigh somewhere between 160-200lbs.

This WILL weigh more in a traditional unibody...thankfully you are adding weight to the center and down below. The weight difference isn't a whole lot, and is certainly offset by the increased performance.

Prodigy,
I understand your point. Keep in mind the floorpan in which the seat bolts to is already raised high above the rest of the floor, and there are a multitude of seat brackets (and you can make/modify your own) to make things work. Not all seats have the same padding height, either. We have a builder who built a car using our chassis for a guy that was about 6'2" (and about 230lbs, big guy), and he fits in there very comfortably. I believe that car was sectioned 3-1/4". This is a common concern for people, but is often not a problem.

TravisB
11-11-2005, 08:51 AM
Prodigy,
I understand your point. Keep in mind the floorpan in which the seat bolts to is already raised high above the rest of the floor,


The factory floor pan in my A-body....the seat mount area is even with the top of the rocker!!!!!! So you would be loosing nothing.

Mean 69
11-11-2005, 11:41 AM
Unibodys are extremely flexible, and that is generally frowned upon. Even with subframe connectors, the chassis is still overly flexible for high-end performance. The springs should be doing the work, not the chassis. A properly designed full-frame will greatly increase strength and solve that issue.

I'll agree 100% that a rigid chassis is paramount for high performance, but I'd really caution against making a statement that a full frame dropped into a uni-body car is stronger than a unit body car with a good set of sfc's. It is really going to depend on how each is executed. The main nasty that shows up in a performance aspect is torsional rigidity, and in and of themselves, neither a ladder type frame, or a unit body car are very good.

However, the unit body cars can become really darned good with the application of a proper set of SFC's, such as the DSE through floor units. The reason is that while a full frame is bolted to the car with eight or so locations, and rubber bushes, the unit body car is welded to all of the frame elements. As such, all of the bent up sheetmetal, i.e. the floor pan, back seat brace, roof, pillars, everything becomes part of the structure, in three dimensions. Still not adequate for ripping up the road course with the C6R Corvettes, but not crap by any means either. All of the those little bends, divets, wrinkles, risers, etc in the factory sheet metal integrate and form a pretty darned stout structure. Compare a tin can with a smooth barrel, to one with the ridges in it, big difference!

Now, in the case you describe, the frame "would" be integrated into the body, much like a unit body car is, but depending on the floor that goes in, still might not be as torsionally rigid. Torsional rigidity is more dependent upon the design of a structure, than it is on the wall thickness of tubes used, take a look at a Maserati birdcage for an extreme example of frame-triangulation. The only way to know for certain if it is indeed more torsionally rigid is to measure it directly, it is super hard to model in FEA, for instance. I'd really be interested in seeing the difference.

Take a look at a contemporary World Challenge race car, those cars really heavily on a rigid chassis, and it is all done through the roll cage. Every tube on there is there for a reason, and it's all about triangles. Most of those cars are unit body cars.

I take nothing at all away from the frames Art makes, they are really nice works of art, really nice quality, and they clearly work pretty well.

Mark

ProdigyCustoms
11-11-2005, 12:43 PM
Race-Rodz,
Prodigy,
I understand your point. Keep in mind the floorpan in which the seat bolts to is already raised high above the rest of the floor, and there are a multitude of seat brackets (and you can make/modify your own) to make things work. Not all seats have the same padding height, either. We have a builder who built a car using our chassis for a guy that was about 6'2" (and about 230lbs, big guy), and he fits in there very comfortably. I believe that car was sectioned 3-1/4". This is a common concern for people, but is often not a problem.

The car built for the 6'2" guy, was that a Camaro? A Camaro seat pan is about 2" below the rocker top at the front edge, and about 3 1/2" below the rocker top at the rear of the pan, making the seat go lower as it goes back. The stock floor actually dips lower then the bottom rocker on a Camaro at the seat pan on the bottom of the car.

If the seat is at the top of the 4" rocker, which it would be in a full channeled application, with the thinnest of seat bottoms, a full grown man cannot ride in it. Also, floor pans that are the same height, or almost the same height as the seat tend to cause circulation problems in the legs on long trips, making it uncomfortable to drive, so building the seat into a recess bucket of sorts is not an option either. I only speak from first hand experiance trying to chassis these cars. We have done it, but there are always sacrifices unless you can get the exhaust out the side with fenderwell outlets, or through the tunnel. Then the floor can be at the bottom of the frame, belly style, curing all the issues. As I said, we just finished one of these. If your frame was modified slightly, changing the exhaust routing, this could be done and would be a popular swap. It would only require changes to the center rails, or removal of the center rails if you think it would be strong enough without those rails.

Silver69Camaro
11-11-2005, 02:14 PM
Prodigy,
I won't name names, but it was a Challenger. The car sat EXTREMELY low and still mainainted 4" of ground clearance, the roof may have been chopped also. But anyway, The seats were angled back a bit to get the man to fit (I asked Craig, he's 6'3").

All in all, this chassis is nothing new. Many builders have been using it, and seat height just hasn't been an issue; there are many ways around it.

Mark,
I agree with your statement wholly. Like you said, the chassis should be welded to the body (and is how we recommend it). I also agree that you really cannot start to dramatically increase torsional rigidity until you triangulate the chassis in some manner (or other means). Simple engineering statics, no big deal. However, we aren't dealing with the type of customer who is willing to turn his Chevelle into a Cup car.

I also agree that unibody cars can be quite good with SFC. Take my car, for example, as I installed DSE SFCs a while back (with solid bushings). Is the car still flimsy? Yeah, it is. Don't get me wrong, it's a world of difference, but it's still not very rigid (and I agree, it's not crap). But, if you were you jack up the car by the rocker (just rear of the front wheel), the front tire will be completely off the ground before rear really starts to rise. This is a rust-free original car w/ no prior accidents.

Now, try this with a new unibody car (RWD, though). The wheels will lift pretty close to the same time. I mention this because I have nothing against unibody cars, and like you said, they can be made quite well (and are often light weight!). Newer technology has greatly enhanced the stiffness of unibody chassis, something that may be lacking with older cars.

The only thing that we can produce is a conventional-type frame that has increased stiffness, both bending and torsion. I apologize if I sounded as if it was the stiffest thing available, but it IS better (through hand and COSMOS evaluations) than factory-stock frames. In my eyes, comparing the torsional strength of this chassis of this chassis to a high-end monocoque or caged chassis would be unfair, it's a whole differrent ballgame.

Well, this post has taken a turn that wasn't intended. My orginal thoughts were to gather some market data on how to ease the predetermined notions of pain about installing these frames. But hey, I enjoy addressing concerns or new ideas.

ProdigyCustoms
11-12-2005, 09:56 AM
Prodigy,

Well, this post has taken a turn that wasn't intended. My orginal thoughts were to gather some market data on how to ease the predetermined notions of pain about installing these frames. But hey, I enjoy addressing concerns or new ideas.

I hope I did not turn the post, this was not my intent as I am a big advocate for full chassis, in fact we just finished using one of your chassis in a 55 Chevy project and we loved it. There was a thread on this subject on another forum, installing it in Camaro's, and the solution proposed by someone then was to eliminate the center rails, as some builders have done. I believe it was Craig that ultimatly came in and said the center rails would be needed, at least in convertibles if I remeber correctly. I really think it is a fantastic chassis, and I love the full frame idea. We have two projects, one in house and another for a client, that both need full frames. Maybe next week we can get some measurements and share some ideas, off the forum, for fitting into a Camaro and curing my concerns.

Mean 69
11-12-2005, 11:35 AM
Please don't take my comments as offensive, and I appreciate the response. The point I was trying to get across is that "if" a person does want a really rigid chassis, it can be done without a full frame install. If a person is really concerned about ultimate cornering, etc, then that person should also be very concerned about safety, which would merit a cage. A cage is an easier install than a full frame as I understand the complexity of the full frame install, it is pretty invasive, and as you pointed out, it adds quite a bit of weight to boot.

You will never be able to eliminate torsional rigidity issues, but for the vast majority of folks, the DSE type sfc's are adequate. Hell, my late model 911 has chassis flex, I can feel it easily, but the car still handles extremely well, and flat hauls ass. I feel less chassis flex in my 69 Camaro than I do with that car, by the way.

M

ProdigyCustoms
11-12-2005, 02:53 PM
One thing about weight Mark. In the Convertible, we lost a substaintial amount of weight doing the chassis. Our weight bill for the steel tubing was 200LBs which did everything from the firewall back including rear crossmember and roll bar materials, + 100LBS for the front stub frame which was firewall forward. The stock front subframe, rear rails and seat partition in the convertible easily weighed 500 lbs. The seat partition alone was so heavy when it hit the ground, Michael and I had to get a vehicle to drag it out from under the car. So without yet having weighed the car, I am certain we picked up at least a couple hundred pounds. A Coupe would not be as drastic because they do not have the superstructure (seat partition) the convertible has.

Rigidity in the full frame, with nothing more then a roll bar / crossmember for cage is super rigid. Much stronger then a sub frame conected car, of coarse I am talking convertible again. We also are talking about a spine and backbone type frame here. With all that said, have doen plenty of uni bodies that are fine with no more then a 10 point cage. My street racer is a great example.

I would like to work out a simlar chassis and possibly use you rear for one of our in house projects which is going to be pretty hard core. It is a choice between your set up and a different independant set up. Maybe we can talk soon. And congratulations on making SEMA with a trick product, I know you guys humped to get it there.

Mean 69
11-13-2005, 11:13 AM
Rigidity in the full frame, with nothing more then a roll bar / crossmember for cage is super rigid. Much stronger then a sub frame conected car, of coarse I am talking convertible again.

THAT!!! Is a really good point, a convertible is where a full frame would shine over an "average" sfc car. And as you pointed out, it gets a whole bunch better, really quick with a roll structure. Man, that convertible cross brace must be a real hulk, I knew they were beefy, I didn't think they were that much though. Great info. We are going to be doing a new frame for my wife's 62 vette here in a few weeks, and another customer car at the same time, so that big ole cross bracing will be a must, as we won't be using a cage on either. Stock frame has a big "x" in it already.

Great stuff, thanks!
Mark

Silver69Camaro
11-14-2005, 08:22 AM
Hey, no offense taken here, guys. More brains on this, the better.

I just intended this post to be about easing fears of installing this chassis, rather than if the design was acceptable or not. That's all, no big deal. :thumbsup:

Mark,
I totally agree. Unibodys can have extremely rigid chassis and can have the benefit of being light weight, which is why I personally am somewhat partial to them.

Prodigy,
I'd be very happy to work with you on measurements and your concerns. I've got my own Camaro to measure from, but as we all know, all of them are not the same. More is better. Shoot me an email in the near future ([email protected]).