72 R code DNA

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72ESA

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1971 Mach 1
1972 Comet GT
Is there a trusted source that itemizes the features that were standard on the 72 R code cars?

I would like to have a check list handy when looking at a potential buy; I’m aware of most of the obvious things, but I don’t consider myself to be qualified to compile an accurate document. If such a thing exists, I would appreciate it if someone could share a link....Thanks!!
 

lalease

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1972 Mach1- long gone
1971 Boss 351- sold 2015
Are 72 R code exhaust manifolds the same as 71 B1? number?
 
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1971 Mustang Sportroof M code
This might help, the '72 facts book:
 

Bobby

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1972 Mach 1
Mach 1s are always Fastbacks or Sports Roof as acknowledged in brochures or Marti Reports. The only exception is Mach 1 convertibles. The 05 designation on your VIN indicates Mach 1 option.
 

Hemikiller

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71 XR-7 coupe
71 Country Squire
65 coupe
Is there a trusted source that itemizes the features that were standard on the 72 R code cars?

I would like to have a check list handy when looking at a potential buy; I’m aware of most of the obvious things, but I don’t consider myself to be qualified to compile an accurate document. If such a thing exists, I would appreciate it if someone could share a link....Thanks!!

72 R-code equipped cars will have all of the following....

"R" in the fifth place in the VIN, denoting the 351HO engine option.
"V" under *axle* on the door data tag - denoting the 3.91 Trac Loc rear axle
"5" under *trans* on the door data tag, denoting the wide ratio 4 speed Toploader transmission
No other transmission or rear axle codes were available, the 351HO was also not available with factory installed air conditioning.

R-code engines were available in any body style or model in 1972, unlike 1971 with the Boss specific model. They carried some unique parts...
D2ZF-GA Motorcraft 4300D carb
D2ZF-JA Motorcraft dual point distributor
D1ZX-CA aluminum intake
B302/B351 style finned aluminum valve covers w/drippers
4* marked heads with screw in studs and guideplates for the 351HO mechanical camshaft
D2ZX marked damper, approx 2" thickness
"N" case rear diff w/WFD-D or D2 axle tag code and 3L91 stamped into the ratio location, staggered shocks and rear sway bar.
Boss 351 used D1ZE-BA & D0AE-G 351C-4V exhaust manifolds, which were machined to 2 1/4" openings, the 351HO most likely used them as well.


To be "numbers matching" and to guarantee that you have the original engine and transmission, you need to find the partial VINs stamped on the rear of the block below the driver's side cylinder head, and on top of the d/s ear of the transmission. The stamping should read 2Fxxxxxx, they do not include body or engine codes.

351c_block_vin_locations.jpg

toploader_vin_stamp.jpg
 

72ESA

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1971 Mach 1
1972 Comet GT
72 R-code equipped cars will have all of the following....

"R" in the fifth place in the VIN, denoting the 351HO engine option.
"V" under *axle* on the door data tag - denoting the 3.91 Trac Loc rear axle
"5" under *trans* on the door data tag, denoting the wide ratio 4 speed Toploader transmission
No other transmission or rear axle codes were available, the 351HO was also not available with factory installed air conditioning.

R-code engines were available in any body style or model in 1972, unlike 1971 with the Boss specific model. They carried some unique parts...
D2ZF-GA Motorcraft 4300D carb
D2ZF-JA Motorcraft dual point distributor
D1ZX-CA aluminum intake
B302/B351 style finned aluminum valve covers w/drippers
4* marked heads with screw in studs and guideplates for the 351HO mechanical camshaft
D2ZX marked damper, approx 2" thickness
"N" case rear diff w/WFD-D or D2 axle tag code and 3L91 stamped into the ratio location, staggered shocks and rear sway bar.
Boss 351 used D1ZE-BA & D0AE-G 351C-4V exhaust manifolds, which were machined to 2 1/4" openings, the 351HO most likely used them as well.


To be "numbers matching" and to guarantee that you have the original engine and transmission, you need to find the partial VINs stamped on the rear of the block below the driver's side cylinder head, and on top of the d/s ear of the transmission. The stamping should read 2Fxxxxxx, they do not include body or engine codes.

View attachment 59770

View attachment 59771

Thanks! This is what I was hoping to see. You didn’t mention the rev limiter, but I was aware of that feature. 😊
 

golfboots

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72 R-code equipped cars will have all of the following....

"R" in the fifth place in the VIN, denoting the 351HO engine option.
"V" under *axle* on the door data tag - denoting the 3.91 Trac Loc rear axle
"5" under *trans* on the door data tag, denoting the wide ratio 4 speed Toploader transmission
No other transmission or rear axle codes were available, the 351HO was also not available with factory installed air conditioning.

R-code engines were available in any body style or model in 1972, unlike 1971 with the Boss specific model. They carried some unique parts...
D2ZF-GA Motorcraft 4300D carb
D2ZF-JA Motorcraft dual point distributor
D1ZX-CA aluminum intake
B302/B351 style finned aluminum valve covers w/drippers
4* marked heads with screw in studs and guideplates for the 351HO mechanical camshaft
D2ZX marked damper, approx 2" thickness
"N" case rear diff w/WFD-D or D2 axle tag code and 3L91 stamped into the ratio location, staggered shocks and rear sway bar.
Boss 351 used D1ZE-BA & D0AE-G 351C-4V exhaust manifolds, which were machined to 2 1/4" openings, the 351HO most likely used them as well.


To be "numbers matching" and to guarantee that you have the original engine and transmission, you need to find the partial VINs stamped on the rear of the block below the driver's side cylinder head, and on top of the d/s ear of the transmission. The stamping should read 2Fxxxxxx, they do not include body or engine codes.

View attachment 59770

View attachment 59771
Can you help me decode my R-Code. Here is a link to a video of the codes I have discovered.
 

fastcobra

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1971 Grande' C code CJ medium brown w/ginger interior.
1971 Mach 1 C code 4spd pewter w/vermillion interior, factory a/c w/35K original miles.
Hopefully someone will comment...I don’t know the answer to that one - without doing some digging.
They are different casting numbers
 
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