What do staggered rear shocks mean?

[scgamecock]

Is the staggered rear shocks an option?  Mine has one in front of rear end and 1 in the rear.  Is this the "drag pack" option or is it just how they all came?

 

[secluff]

scgamecock, staggered rear shocks were not a stand alone option. The competition suspension was standard on the Mach1 (regardless of engine size) and the staggered rear shocks were included with the 4bl 351 and 429 engines. The competition suspension was an option on all other Mustangs except the 250 6 cyl and was a mandatory option on any F60x15" equipped vehicle.

The staggered rear shocks were Ford engineers attempt to control rear axle wind up. With the sudden application of large amounts of torque (such as on 4sp cars) the differential was twisting and causing the leaf springs to twist and the  rear wheels to bounce up and down. From 68-70 Ford used staggered rear shocks on 4sp cars. From 71-73 Ford also included the staggered shocks on A/T equipped cars with 4bl engines.

The Drag Pack option was only available on the 429 cars and included many engine enhancements and a choice of 3.91 or 4.11 differential gears (3.91 or 4.30 on Torinos). AC was not available on Drag Pack cars.

 

[scgamecock]

scgamecock, staggered rear shocks were not a stand alone option. The competition suspension was standard on the Mach1 (regardless of engine size) and the staggered rear shocks were included with the 4bl 351 and 429 engines. The competition suspension was an option on all other Mustangs except the 250 6 cyl and was a mandatory option on any F60x15" equipped vehicle.

The staggered rear shocks were Ford engineers attempt to control rear axle wind up. With the sudden application of large amounts of torque (such as on 4sp cars) the differential was twisting and causing the leaf springs to twist and the  rear wheels to bounce up and down. From 68-70 Ford used staggered rear shocks on 4sp cars. From 71-73 Ford also included the staggered shocks on A/T equipped cars with 4bl engines.

The Drag Pack option was only available on the 429 cars and included many engine enhancements and a choice of 3.91 or 4.11 differential gears (3.91 or 4.30 on Torinos). AC was not available on Drag Pack cars.

So since I have the staggered shocks my car came factory with the 351c 4bl and 15" rims??  Would it also indicate a posi rearend?  What gear ratio would it mst likely come with since it is a Q code 4 speed car?

 

[delawarebill]

look on drivers door for that info. or jack up rear and turn one tire and the other will turn in same direction... if it turns the other way it's open rear.

 

[jpaz]

Could have come with many different gears. But if your car is an a/c car then the tallest gear you could get would be a 3.25 and could be posi or open.

 

[Hemikiller]

Could have come with many different gears. But if your car is an a/c car then the tallest gear you could get would be a 3.25 and could be posi or open.

3.25 was the only gear you could get with a 351CJ and A/C.

 

[red351]

Mach I was just an appearance package, so comp suspension depended on what engine option. The only suspension thing Mach offered standard was wider E-70 tires over E-78

 

[Carolina_Mountain_Mustangs]

Could have come with many different gears. But if your car is an a/c car then the tallest gear you could get would be a 3.25 and could be posi or open.

3.25 was the only gear you could get with a 351CJ and A/C.

After I broke three 3.25 rears in my Mach 1 Ford rep. told them to put a 3.5 in mine with air, lol. They had also put the small u joint 9" in my Q code which they also changed. This was done under warranty over 6 month period of time.

 

[secluff]

scgamecock, As I posted earlier the Competition Suspension is standard on the Mach1 regardless of engine size. The staggered rear  shocks were included with any 351 4bl or 429 powered car.

Since your car has factory AC the 3.25 gear was mandatory.  The 3.50 gear would be the standard gear with no AC and a 4sp. To see if your car was equipped with "Traction Lok" from the factory you can check your door tag under "Axle" and look for "9" (3.25 non locking) or "R" (3.25 locking). There is also a tag that was on the front of the differential that would show 3L25 if a locking or 3.25 non locking. Of course a lot of those got tossed along with all the other tags we now pay a fortune to get reproduced!!

And...you can always do the test as delawarebill  suggested and jack the rear of your car up and turn the wheel and watch to see what direction the other wheel turns.

If you don't already have one, a Marti report would be a nice piece of documentation to have for your car .Gives you a pretty good ideal how your car left the factory.  Since it's getting close to the end of the year, that would also be a great gift ideal for someone in your family who struggles with what to get that "Car Crazy" person in the house!!  

 

[Hemikiller]

Mach I was just an appearance package, so comp suspension depended on what engine option. The only suspension thing Mach offered standard was wider E-70 tires over E-78

ALL Mach 1's received the Competition Suspension package, regardless of which engine you purchased. 302-2V and 351-2V received higher rate springs and stiffer shocks, and the variable ratio box if P/S was ordered. When you ordered any of the 351-4V or 429s, you also received staggered rear shocks, rear sway bar and an upgraded front bar.

IIRC, the the standard spring rates were in the neighborhood off 250 lb/in frt & 78lb/in rear. CS cars were around 400 lb/in frt & 135 lb/in rear. That's a difference you can feel.

 

[red351]

Well the fact is. I must have gotten the shaft, because, I still have my original H code Mach I I ordered back in Jan 1972 from Condit ford in Newton NJ. If you CARE too look and check my vin in PERSON. I will put the car on the lift and you tell me I'M wrong. The real facts is in the writing. READ THEM. IF you have the original sales brochure from (let say) 72. There was no Vari ratio power steering . SPRINGS, I really can't prove that ( Rears springs been replaced). My new leaf springs had a much flatter arch (unloaded) compared too my original's, because I wanted comp style springs SHOCKS, Ford didn't care, as long as it had some. My original oil pan was so beat up (as a kid), that I made a skid plate. SO much for stiffer shocks. My parts cars {Couple's} had the same shocks. My wife's 67 coupe should have had been a S code 390, just by measuring front coils and comparing to factory Eaton spring specs. FACT WAS, It was only a C code 289. There is a lot of inaccurate information out here. I really don't care to argue the facts, as I'm too old too care. The fastbacks got the same suspension as a Mach, just E-70 not 78's

 

[scgamecock]

Out of curiosity why did the A\C option dictate the rear gear size???

 

[jpaz]

It was because Ford didn’t want the a/c components spinning so fast on a regular basis is my best guess. You could get lower gears, 3.00, 2.75 and so on, just nothing more than the 3.25.

 

[secluff]

scgamecock, just as jpaz posted, it came down to the limitations of the AC compressors. At the time Ford was using York and Tecumseh AC compressors which were as good as any in the 70's. In fact the Tecumseh which had a cast iron housing was used in a lot of F600-F800 trucks with factory air.

The problem with the 3.91, 4.11, 4.30 cars was the extreme load imposed on the compressors when the sudden increase of extreme RPM's subjected them to stress they just were not engineered to handle. In fact in the 60's you could not get AC with any solid lifter engine since Ford knew how they were geared and how they would be driven. (High perf 289, 66 Police Interceptor 428, 427's and all Boss engines)

 

[Hemikiller]

Well the fact is.    I must have gotten the shaft,   because,  I still have my original H code Mach I I ordered back in Jan 1972  from Condit ford in Newton NJ. If you CARE too look and check  my vin in PERSON.   I will put the car on the lift and you tell me I'M wrong. The real facts is in the writing. READ THEM. IF you have the original sales brochure from (let say)  72. There was  no Vari ratio power steering .  SPRINGS,   I really can't prove that ( Rears springs been replaced). My new leaf springs had a much flatter arch (unloaded) compared too my original's, because I wanted comp style springs  SHOCKS, Ford didn't care, as long as it had some. My original oil pan was so beat up (as a kid), that I made a skid plate. SO much for stiffer shocks. My parts cars {Couple's} had the same shocks.    My wife's 67 coupe should have had been a S code 390, just by measuring front coils and comparing to factory Eaton spring specs. FACT WAS, It was only a C code 289.    There is a lot of inaccurate information out here.  I really don't care to argue the facts, as I'm too old too care. The fastbacks got the same suspension as a Mach, just E-70 not 78's

So let me get this straight- these are the facts, don't dispute my facts, but I'm not going to back up my facts so don't question my facts. Speaking of inaccurate information, that post above is a bunch of it. Apparently, you are not too old to care. 

Fact - ALL Mach 1s had some flavor of the competition suspension package as standard equipment. 2V cars didn't get the rear bar or staggered shocks. 

Fact - Variable ratio steering was included with CS if you opted for power steering

Fact - CS springs and shocks were unique to the package and varied depending upon option load out. 

Supporting docs - see attached image below with snips of the 71 Facts book. You can view it at this link:

https://www.7173mustangs.com/attachment.php?aid=11017

also attached 1972 rear spring chart from the 65-75 MPC. Notice the different spring callouts w/ and w/ CS springs and that ALL 63R body code springs have "w/competition suspension" noted. 

::thumb::

 

[scgamecock]

scgamecock, just as jpaz posted, it came down to the limitations of the AC compressors. At the time Ford was using York and Tecumseh AC compressors which were as good as any in the 70's. In fact the Tecumseh which had a cast iron housing was used in a lot of F600-F800 trucks with factory air.

The problem with the 3.91, 4.11, 4.30 cars was the extreme load imposed on the compressors when the sudden increase of extreme RPM's subjected them to stress they just were not engineered to handle. In fact in the 60's you could not get AC with any solid lifter engine since Ford knew how they were geared and how they would be driven. (High perf 289, 66 Police Interceptor 428, 427's and all Boss engines)

Hmmm this kinda throws a curve ball at my engine and rear end plans.  I was planning on running a solid flat tappet cam and 3:90 gears. :-/ :-/  I don't plan on drag racing the car so routine high rpms wouldn't be an issue.

 

[73pony]

3.90 gears and a 4 speed you would be turning some pretty high rpms just cruising on the highway. Assuming a 26" tall tire at 70 mph you would be turning over 3,500 rpm. Just a heads up.

 

[red351]

Well Mr. Hemi. The fact is, I'm glad you posted it in fords own words as to WHAT CAME STANDARD with the Mach vin #05. CS was only STANDARD if it was a 4V engine. There was no 4V 302. The 302 2V was the base engine. The 2V 351 option would cost you about $40 more. The standard Mach came without CS, so there would be no V-R steering, no HD suspension, or rear sway bar. It all very clear, if you would sit down and read ALL OF IT.

No need to apologize

 

[Carolina_Mountain_Mustangs]

scgamecock, just as jpaz posted, it came down to the limitations of the AC compressors. At the time Ford was using York and Tecumseh AC compressors which were as good as any in the 70's. In fact the Tecumseh which had a cast iron housing was used in a lot of F600-F800 trucks with factory air.

The problem with the 3.91, 4.11, 4.30 cars was the extreme load imposed on the compressors when the sudden increase of extreme RPM's subjected them to stress they just were not engineered to handle. In fact in the 60's you could not get AC with any solid lifter engine since Ford knew how they were geared and how they would be driven. (High perf 289, 66 Police Interceptor 428, 427's and all Boss engines)

Hmmm this kinda throws a curve ball at my engine and rear end plans.  I was planning on running a solid flat tappet cam and 3:90 gears. :-/ :-/  I don't plan on drag racing the car so routine high rpms wouldn't be an issue.

Run any gear you want just do not turn on the air when you are going to wind it up. The compressor is not engaged by the magnetic clutch unless you turn on the air inside the car. One of the first things I did when I got my car brand new was to pull the belt off the air cond., lol. Needed all the HP I could get.

Build the car you want and put into it what you want.