m, r, s code ??

[MatteMan]

Hello

I wonder what the difference is between M-code R-code and S-code ?

 

[Max Power]

Those are engine codes for various years. The M code is a 4v 351, S is a 390, and R is a 428 with Ram Air option. Ford used a Q code for non-Ram Air 428s, and H for 351 2vs, and F for 302s, and A,C or K for 289s and codes for 6 cylinders I never paid any attention to!

 

[MatteMan]

okej, thanks!

 

[likesoldjunk]

What about Q Code 351's ?

 

[Max Power]

Yup, they started in 1971, I believe, after Ford quit making the non-ram air 428s.

 

[96 DOHC Cobra]

The "Q" code was also used for 66-68 regular 428s and 72-74 351C 4V motors.

 

[390Fe]

Lets really confuse the poor guy... in 1971 R code stood for Boss 351; in '72 it was the HO 351 (an 8.8 compression ratio Boss 351), In 69 and 70 "G" was a Boss 302

 

[Max Power]

Don't forget the X codes!!!

 

[390Fe]

Yup, they started in 1971, I believe, after Ford quit making the non-ram air 428s.

Wasn't "Q" used for the '71 429 CJ and SCJ? ARrgh! I'll stick to '69: F, G, H, L, M, Q, R, S, T, and X Whheeee!
(sorry, bad day at work)

 

[65Mustang2+2]

oh yeah, what about the little W- code "427" engine! Not in a Mustang though..... Too Bad.

 

[McFairmont]

71 429`s

Wasn't "Q" used for the '71 429 CJ and SCJ? ARrgh! I'll stick to '69: F, G, H, L, M, Q, R, S, T, and X Whheeee!
(sorry, bad day at work)

Nope, the 360HP 429 Thunder Jet (big car & Torino-Montego) was coded "N"
The 429CJ was a "C"
the 429SCJ was "J"
On the 428`s, the non CJ versions were "Q", but these engines were only used in the Galaxie,full size Mercs &Tbirds. These cars never had the Cobra Jet version.
Also these "base" engines never came in a Mustang/Cougar, or Torino/Cyclone , only the 428CJ-SCJ in these cars.
So, in 68 & 69, there were 2 different "Q" code 428`s availabl, the base version in the larger cars, the CJ in the unibody smaller cars.

 

[390Fe]

Nope, the 360HP 429 Thunder Jet (big car & Torino-Montego) was coded "N"
The 429CJ was a "C"
the 429SCJ was "J"
On the 428`s, the non CJ versions were "Q", but these engines were only used in the Galaxie,full size Mercs &Tbirds. These cars never had the Cobra Jet version.
Also these "base" engines never came in a Mustang/Cougar, or Torino/Cyclone , only the 428CJ-SCJ in these cars.
So, in 68 & 69, there were 2 different "Q" code 428`s availabl, the base version in the larger cars, the CJ in the unibody smaller cars.

Thanks... Now I remember - your reply finally percolated those codes to the top... And in all honesty I've never known what the full size codes were - thanks again