Mustang II Suspension questions

[Frijolito1988]

Hey guys so i am piecing together my Mustang II front clip. This is going to be a 56 GMC SWB.

So far What i know I have with the help of the forum.

Aftermarket MII Crossmember

Stock MII upper and lower control arms

Stock Mustang II spindles

9 1/4'' rotors that are 5x4.75 lug pattern ( camaro )
( I think these are aftermarket rotors that go on mustang II spindle but have a 5 lug camaro/gm car patern )


Now my question.

-Should i use the stock MII calipers and 9 1/4'' rotors ? Enough stopping power for a 56 GMC truck , small block, no racing just going to be used for cruising.

-Should i use the stock Coil springs and Shock / Strut ? Or are there aftermarket ones for the increased weight ?


Much appreciated.

[Speedbumpauto]

Not a chance! Maybe marginal with power booster. On my 27 roadster I started with the Mustang brakes/rotors in a Ford pattern. Was unhappy even in an 1800 lb. car. Bought the kit for the 11 inch rotors/GM calipers for the Mustang spindle and it made a huge difference. IMO, don't even waste your time. I have a complete set, but in a ford pattern I'll sell you cheap!

[J48chevy]

Go with the 11" rotors. I bought mine from southern rod and parts and just starting to put it all on. Nice kit and the good news is if you select GM pattern rotors they also come pre drilled for ford bolt pattern also so you can choose either one. Here is the link. Not expensive either.

http://www.southernrods.com/chassis-...vy-pickup.html

[oldman3]

X3, go with the larger rotors and calipers, will be alot happier...Jim

[Frijolito1988]

Thanks guys! Much appreciated.

Now should stock MII coilsprings and shocks suffice ?

[Speedbumpauto]

Again, no....or maybe marginal with a small block with alum. intake and headers and no AC, PS etc. You've saved about as much as you can by using the spindles and control arms....and I'd even be suspect of the stock lower control arm using the short bushing and the strut rod set-up. By the way, you need to confirm your crossmember will take a stock lower unit. Many are made to take the aftermarket ones that use two bushings in the more traditional A arm configuration. You'll also have to weld in mounts for the strut rods somewhere in your fabrication plan. By the time you buy strut rod bushing kits, etc., you might be close to the cost of aftermarket control arms. Just something to think about.

[Frijolito1988]

Originally Posted by Speedbumpauto

Again, no....or maybe marginal with a small block with alum. intake and headers and no AC, PS etc. You've saved about as much as you can by using the spindles and control arms....and I'd even be suspect of the stock lower control arm using the short bushing and the strut rod set-up. By the way, you need to confirm your crossmember will take a stock lower unit. Many are made to take the aftermarket ones that use two bushings in the more traditional A arm configuration. You'll also have to weld in mounts for the strut rods somewhere in your fabrication plan. By the time you buy strut rod bushing kits, etc., you might be close to the cost of aftermarket control arms. Just something to think about.

Actually i purchased a SWB frame that already had a camaro rear end and the MII crossmember A arms ect just needed the coils/shocks and brakes.

This is how i got it. Paid $600

[Frijolito1988]

So i see speedwaymotors sells this complete kit to convert to GM 11' rotors / brakes. I am going to give them a call and order this ASAP.

http://www.speedwaymotors.com/Mustan...tern,2007.html

[slimneverdies]

Do you guys know of any one who sells a 11" rotor that has the 5 on 5 or 5x127 bolt pattern for the mustang ll spindles???

[Dan in Pasadena]

Frijolito,

Is this the frame that was on local SoCal Craigslist for quite awhile, I think the asking price was $695? If so, I REALLY considered going to look at it but didn't in the end because I simply don't have the space to store it/tear my truck down right now.

Did you carefully measure not only the "square-ness" of the wheel base but also the frame overall with side-to-side and diagonal measurements?

How about some pics of your truck as it is now?

[mr48chev]

Originally Posted by slimneverdies

Do you guys know of any one who sells a 11" rotor that has the 5 on 5 or 5x127 bolt pattern for the mustang ll spindles???

They may exist but I haven't seen any that I know of. Most 5 on 5 GM rotors are a larger diameter than the 11 inch ones that are on most 5 on 4-3/4 brake setups.

The speedway kit you posted the link to is probably more than competitive with going out and buying the brake parts individually and it sure saves a lot of head scratching and pondering while making the brake swap a couple of hours process.

[oldman3]

Originally Posted by Frijolito1988

Thanks guys! Much appreciated.

Now should stock MII coilsprings and shocks suffice ?

Lots of guys seem to make them work, but not for me. If you go to page 23 post #567 of my build thread I have a write up on what I did (build thread in signature below)...Jim

[mr48chev]

Stock coil springs are usually up to the task on one of these trucks and as the weight bias is a lot different on the truck than on a stock MII the springs may be too stout for the truck. I'd probably want to go to at least an upgrade version of the stock shock.

[slimneverdies]

Originally Posted by mr48chev

They may exist but I haven't seen any that I know of. Most 5 on 5 GM rotors are a larger diameter than the 11 inch ones that are on most 5 on 4-3/4 brake setups.

The speedway kit you posted the link to is probably more than competitive with going out and buying the brake parts individually and it sure saves a lot of head scratching and pondering while making the brake swap a couple of hours process.

You guys think there's enough space on the rotors to get the 5 on 5 bolt pattern drilled on them??

[solidaxel]

May want to check for bump steer on that rack and pinion, looks like the spacer is in the wrong position

[_Ogre]

Originally Posted by solidaxel

May want to check for bump steer on that rack and pinion, looks like the spacer is in the wrong position

good catch solidaxle; there is no rack spacer, it looks like the po extended the tie rod with threaded rod.
that looks like a fatman x-member to me, my fatman is 3x4 tubing welded to the bottom of my frame
you can buy the rack spacer at any mustII fabricator, 4'' or 4.5'' if using the tbird rack

i added 4'' channel gussets on the frame for torsional strength but this is my fatman x-member
i strongly recommend the gussets (the engineerd in me)