mini tub my 56

I have this 56 Ford 2dr sedan project I am building. I have been saving my pennies for awhile and collecting parts for a few years and it is just about time for some chassis work. This will be a street car so no cage (I want to keep the back seat) but I want to do a 2x4 rear clip and mini tub to fit 325 drag radials. For a rearend I am looking at a backbraced 9", 35 spline axles and S-trac. As far as suspension goes I am still out on that decision. I looked at 4 bars, 4 links, triangulated 4 bars and leaf spring/caltracs. I spoke with Morrison about doing a whole frame and I spoke with Wizard race cars about the back half. I don't expect this to be cheap so I would really like to get 1 or 2 more quotes and opinions/feedback. I live in Louisiana and work in West Texas so area wise I don't mind taking it within a state or 2 radius for a quality job.

Power wise I have a 460/aod for it.

Refresh my memory, do they have an actual chassis/frame, or are they a uni-body?

IMO........

If it has a "real" factory frame and isn't getting a cage then back-halfing it (or full framing it) with 2x4 tubing (vs 2x3, or all round tube) is the way to go. And if the factory frame isn't "boxed" (like an open "C" channel frame) the it's probably best to box it while the body is off. It should be mentioned that even with 2x4 tubing it still might flex/bow some without a cage. So it might be wise to use rubber body-to-frame mounts vs using urethane or solid body mounts.

On a true street driven car ladder bars are pretty much out of the question IMO since they don't allow any body-roll/suspension articulation. Either the parallel 4 bar and/or the triangulated 4 bar setups are probably the best choices for ride quality. If you could get a triangulated 4 bar to somewhat mimic the Fox Body layout then some of the design work is kinda already done for you.

One down side of not using a cage is if it was going to be a full chassis/frame build that kinda rules out using a Fox/SN95 strut front suspension setup & limits you to an A-arm front suspension.

What about using a real tight fitting cage half/all hidden in the head liner (if possible) with bolt-in door bars (not swing-out) that could be fully removed when driving on the street?

I would go with a 35 spline Detroit Locker on the street.

You could go with coilover shocks having rubber (or urethane) bushings, vs leaf springs. But sometimes the rubber/urethane C/O shock bushings don't last very long on the street depending on car weight & how many rough street miles it sees. Another option is to do like the old Super Stock guys had to do and mount a coil over shock's spring in it's own "cup" mounts separate from the shock mounts. That way the spring is caring all the car weight & not the C/O shock's bushings.

Yes Dave it is a full frame.







Originally I was thinking of something along the lines of this S10 rear clip (from Autoweld) but I don't see fitting a 4 link in there without getting into the seat area or doing a short unequal length 4 link. Even thought it is a street car I still want it to hook up so some adjustability would be nice.

DILLIGASDAVE wrote:

On a true street driven car ladder bars are pretty much out of the question IMO since they don't allow any body-roll/suspension articulation. Either the parallel 4 bar and/or the triangulated 4 bar setups are probably the best choices for ride quality. If you could get a triangulated 4 bar to somewhat mimic the Fox Body layout then some of the design work is kinda already done for you.

When I spoke with Morrison they didn't really recommend a triangulated 4 link for drag tires and racing. Morrison along with most other street rod stuff put the upper bars if front of the axle tubes to clear the floor area unlike a foxbody setup where they are on top of the housing. I would think you would lose all your leverage with that type of design.

DILLIGASDAVE wrote: One down side of not using a cage is if it was going to be a full chassis/frame build that kinda rules out using a Fox/SN95 strut front suspension setup & limits you to an A-arm front suspension.

DILLIGASDAVE wrote: What about using a real tight fitting cage half/all hidden in the head liner (if possible) with bolt-in door bars (not swing-out) that could be fully removed when driving on the street?

I really like the way you are thinking there. Can you do a rear bolt in cross bar for back seat access?

DILLIGASDAVE wrote:I would go with a 35 spline Detroit Locker on the street.

 Why do you like the locker over the S-trac? I have never had either so I have no idea.

Have you tried M&M Chassis Shop in Moselle, MS? Or Wicked Chassis in Denham Springs?

I don't see why you couldn't do a triangulated 4 bar deal like a Mustang. Not sure why the uppers need to be mounted in the middle of the housing. Why not put them up top like a Mustang? Your floor will dictate the bar placement in the end... Can you get under the car now at your desired ride height and mock up some bars to see what suits it best?

jasonf wrote:When I spoke with Morrison they didn't really recommend a triangulated 4 link for drag tires and racing.

jbozzelle wrote:I don't see why you couldn't do a triangulated 4 bar deal like a Mustang.

I'm just guessing but maybe AM means in their opinion the triangulated/Foxbody setup doesn't work well in a drag situation with a big tire (???).

jasonf wrote:Morrison along with most other street rod stuff put the upper bars if front of the axle tubes to clear the floor area unlike a foxbody setup where they are on top of the housing. I would think you would lose all your leverage with that type of design.

You probably still get some usable amount of rotational "push/pull" leverage action happening. But the thing that has me wondering about that setup is what will happen to the pinion angle having that top bar mounting point being on the front of the axle tube (vs on top of the axle tube). I would think it might do something wonky to the pinion angle as the rear axle moves through out the suspension travel.

jasonf wrote:Can you do a rear bolt in cross bar for back seat access?

Not and still be NHRA/IHRA 8.50 legal. The seat cross bar has to be welded in and be at a height to (A) support the seat back & (B) have the correct shoulder harness attachment point height for the driver.

jasonf wrote:Why do you like the locker over the S-trac?

Meh, I'm old and set in my ways.  The D-Locker is technology that has been around forever and will usually take a decent amount of abuse.



I guess another option is a torque arm setup since they allow plenty of body-roll/articulation (maybe too much?) for street driving. Even something like the NASCAR rear suspension stuff might work on the street even though they are in effect like two really long ladder bars. But since they point inward a bunch at the front attachment point they do allow some body-roll.

And another option for stiffening up the chassis (if a cage isn't used) is to install a tubular back-bone structure running nose-to-tail hidden inside the trans/driveshaft tunnel. It's kinda like a Pro Mod's double frame rail, but on a smaller scale and hidden. You do have to make the trans tunnel a little bit bigger/wider/taller to get the back-bone in there. But it's not really a problem unless you want to use a bench seat vs bucket seats.



[edit] Also a 3-link might be another option.....

Heh, messing with Photoshop a little, SLAM-SLAM! Shave off the rocker panels so the bottom edge of the door is now the bottom of the body. Channel the body down over the chassis/raise the floor up over the chassis + air bag suspension.

DILLIGASDAVE wrote:Heh, messing with Photoshop a little, SLAM-SLAM! Shave off the rocker panels so the bottom edge of the door is now the bottom of the body. Channel the body down over the chassis/raise the floor up over the chassis + air bag suspension.

Pretty cool but I am taller upstairs so I need all the head room I can get. No channeling in my future. lol

jasonf wrote:........Morrison along with most other street rod stuff put the upper bars if front of the axle tubes to clear the floor area unlike a foxbody setup where they are on top of the housing. I would think you would lose all your leverage with that type of design.

Looking at this pic again raises more questions. How does rotating the top bar housing mount down to the front face of the axle tube make more room for the rear seat if the rear frame rail kick-up it's self (going over the housing) is still in the way? To me it seems like if the floor going over the frame kick-up clears the rear seat, then a top bar housing mount placed on top of the axle tube should clear as well.

Well this is a universal photo but very much like the stock frame. Right where the bend up starts is were the trunk floor starts. The floor pretty much stays about 1" above the frame detail. A frame like this is meant to fit the stock sheet metal as much as possible. If you raise the bar up it would be in the floor/seat area.


BTW, here is a 56 with 3" drop spindles via Fatman. That gets it pretty low.

Went and read some more on the NASCAR/60's-70's chevy truck long trailing arm rear suspension. Looks like a lot of people have made them work well on the street on everything from heavy long wheelbase lead-sleds to lighter/shorter model A's. Supposed to have a real smooth ride too.

The factory 60's-70's chevy truck arms were an I-beam design. The modern NASCAR stuff is made of two channels welded together back-to-back to form an I-beam. And then there is some of the aftermarket street rod stuff that is made of 2x2 or 2x3 tubing instead of some form of an I-beam.

Some say that the desired body-roll/articulation comes from the I-beam material flexing/twisting, and that  2x2 or 2x3 tubing is the wrong way to go because it won't flex enough. But others say that the body-roll/articulation comes from the arms pointing inward at the front mount, (and their long length) and that either material will work OK.

Some put the spring coilovers (or air-bag coilovers) behind the housing. While other people use a spring (or air-bag) in front of the housing on the trailing arm it's self with a separate shock either in front or behind the housing. Also the panhard bar needs to be made as long as possible, and parallel to the ground as an adjusting starting point. So that probably means it's best to mount a panhard bar behind the housing (and the springs/shocks in front).

Also read where some claim they will hook well at the strip on a drag car/truck combo too. That had me kinda confused since I had always heard that they were kinda prone to wheel-hop in a drag situation. But I have no idea if it's true or not.

I originally had thought about doing a truck arm because of the all around benefits you mentioned. Farmtruck seems to make it hook. No limit Engineering uses a johnny joint in the front of square tubing to allow the axle to roll. One downside is packaging when it comes to exhaust. And the weight if that is a concern.

jasonf wrote:I have this 56 Ford 2dr sedan project I am building. I have been saving my pennies for awhile and collecting parts for a few years and it is just about time for some chassis work. This will be a street car so no cage (I want to keep the back seat) but I want to do a 2x4 rear clip and mini tub to fit 325 drag radials. For a rearend I am looking at a backbraced 9", 35 spline axles and S-trac. As far as suspension goes I am still out on that decision. I looked at 4 bars, 4 links, triangulated 4 bars and leaf spring/caltracs. I spoke with Morrison about doing a whole frame and I spoke with Wizard race cars about the back half. I don't expect this to be cheap so I would really like to get 1 or 2 more quotes and opinions/feedback. I live in Louisiana and work in West Texas so area wise I don't mind taking it within a state or 2 radius for a quality job.

Power wise I have a 460/aod for it.

I just wanted to say this thing is COOOOL
You mentioned the exhaust being challenging on the rear with future modifications, you could do a short dump with a few free flowing mufflers per side to keep things quiet and away from the rear suspension.

What a COOL project.

I love it.

Good luck in getting it figured out. Post plenty of pictures along the way.

I am still waiting on Wizard but I put some 28.5" tires on the back of my car today (they are close to the same height as my drag radials) and I am not sure I like the look how I thought I would. I like the stance but the satin black wheels/white walls and polished center caps aren't doing it for me. Something looks off.
The original wheels were light blue and the center caps should have white around the lettering. It's like it's confused whether it is a 60 super stock car or a 50's classic.

I don't know...........

I had a 56 just like this, same color with a white top. It was 1963 just out of high school. I really hate to say this, but I totally destroyed that car in 9 months. What a dumb A S S I was.
Maybe some full 56 Ford hub caps if your not wanting newer wheels. I do like the Welds you had on the front.

QA1 has a chebby truck/NASCAR trailing arm type setup that has a short adjustable link at the back of the arm for adjusting pinion angle. Makes it so you don't have to adjust the pinion angle with wedge shims normally used on a trailing arm.

The down side of their design is it puts the adjuster link right where the coil spring/air bag normally sits on a traditional trailing arm setup (in front of the housing on the arm it's self). That means with the QA1 setup the coil spring/air bag/coil over shock has to go either behind the housing tube, or on top.

http://www.hotrod.com/articles/1005rc-1951-mercury-no-limit-engineering-installs-trailing-arm-rear-suspension/

res0rli9 wrote:http://www.hotrod.com/articles/1005rc-1951-mercury-no-limit-engineering-installs-trailing-arm-rear-suspension/

A couple years ago I looked at doing that system. They are supposed to be a nice compromise with the ride as well as traction.

When I went to pull my hubcaps off the powder coating I had done several years ago flaked off like a cheap spray can job. I was pretty disgusted so I ordered the wheels I wanted to upgrade to later anyways.

17x7's for the front with 215/55-17's
15x10's for the rear.

The 17's are to clear this 13" brake upgrade I have been working on using 2014 Mustang GT brakes. This is the second rendition and is in mdf to check hole alignment.

jasonf wrote:When I went to pull my hubcaps off the powder coating I had done several years ago flaked off like a cheap spray can job. I was pretty disgusted so I ordered the wheels I wanted to upgrade to later anyways.

17x7's for the front with 215/55-17's
15x10's for the rear.

Mmmmmmmm............. race cary

I'm digging the brake upgrade! What are you doing for the back?

jbozzelle wrote:I'm digging the brake upgrade!  What are you doing for the back?

I'd like to do a OEM rear brake but all the new stuff is too big for 15" wheels. I could do an older 11" Mustang deal or I might just let wizard do a Wilwood deal that way I don't have to mess with it. I will have to remember to ask them when I drop the car off.

jasonf wrote:17x7's for the front with 215/55-17's, 15x10's for the rear.

I'm kinda thinking it might look a little weird with 17's on the front & 15's on the rear. Why not just put 17's all around, or 17's on the front & 17+ on the rear?