Question about 1971 engine codes

A nice looking (on the outside and interior) M code 1971 Mach 1 with 4 speed and 3.25 Trac-loc is coming up for sale in a farm auction soon. It is advertised as having only around 14 000 miles. Unfortunately, the car looks like there is a lot more rust on floors, frame and torque boxes than 14000 miles could inflict. There is enough wrong to indicate it is more like 114000 even though the car still has original looking raised white letter polyglas Firestones on it.

Anyway, I don't know many details about 1971 cars when it comes to engine codes and wondered if others could help with the following questions. As mentioned the car is an M code but it appears to have ram air. Is ram air identifiable as legit according to codes on 71 cars and if so does an M code with ram air make sense?

What is the difference between an M code and a Q code in 1971? Do both have 4 bolt mains?

The production date looks like March of 1971 so fairly late in production if that matters with regard to codes and options.

I'm just curious about the differences in 1971 351 4 barrel cars. It looks like it could be a great car with the 4V 351, 4 speed and trac-loc but not for me.

Thanks in advance for any info.

Dan

My understanding is that the M and Q codes shared the same engine but the Q code came with factory Ram Air while the M code did not. 1971 Mach 1's equipped with factory Ram Air (Q codes) are very rare with only 66 being produced.

Great questions.

1971 M codes are VERY common. Desirable, yes. But rare, no way.

1971 Q codes are extremely rare and desirable.

1971 Q codes were supposedly not available until April 1971...

Q codes all had 4 bolt mains. M codes could be either????? I THINK some - if not all M codes were 2 bolt mains.

I am not so sure about the ram air on 1971 Mustangs. I do know that "RAM AIR HOOD" on the invoice and/or Marti does not indicate functional ram air. It just indicates the type of hood.

"DUAL RAM INDUCTION" indicated both the ram air hood, (aka "Mach 1" hood) plus the functional hardware to make it work. As most of you already know - except for some very early 1972 Q codes, for 1972 and 1973 only 2v motors could be ordered with Ram Air Induction.

I hope this helps.

Ray

I could be wrong, but I believe the only 71's to have ram air standard were the "J" code 429 and the Boss 351. Ram air was a RPO (regular production option) for the M and Q 351's. There were some differences in intakes, carbs, and cylinder heads etc to make them definitely two different engines. My M codes are two bolt mains. I've had 4 1972 Q code 351's that were all 4 bolt mains. With so few of the 71 Q 351's built, I have not run into anyone who has owned one so as to verify the type of block used. If anyone has access to a copy of the 65-72 parts catalog they could check basic # 6010 to see what block was used. Hope this helps some!

While there are quite a few M codes that were produced in 71, there were only 4,491 M codes that came with a 4 speed toploader. Personally, I find that combo fairly rare and quite desirable. For me, it's really the next best thing after a J code, Boss/72 R code. Then again, perhaps I'm biased, as my 71 Mach 1 is a M code with a 4 speed toploader

As far as Ram Air, my 71 M code came with it and it is listed on the Marti as "Ram Air Option"

There is a copy of the 71 Mustang Information book on the site. Click on "Data" at the top of the page and click on 71 Mustang Facts.

Fun to read.

-Also check our WIKI for the 1971 Facts Book. Great info!

While there are quite a few M codes that were produced in 71, there were only 4,491 M codes that came with a 4 speed toploader. Personally, I find that combo fairly rare and quite desirable. For me, it's really the next best thing after a J code, Boss/72 R code. Then again, perhaps I'm biased, as my 71 Mach 1 is a M code with a 4 speed toploader

As far as Ram Air, my 71 M code came with it and it is listed on the Marti as "Ram Air Option"

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I agree with the desirability part. I have always considered a 71 M code 4 speed car being very close to a Boss 351. Apparently many others back in 1970 & 1971 (when the cars were new) thought the same and bought them! Over 10K M code 71's sold - don't have my book handy but I know I am close at least for the Mach 1's.

Cool cars.

Ray

There is another thread running right now where member is buying a Q code for I think 25K.

There is another thread running right now where member is buying a Q code for I think 25K.

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Yes, but a 71 Q code.. One of the rarest of all 71-73s.

This one is not a Q, (I got the Auctioneer to message me the first 5 digits of the VIN), it is an M code but in the photos it does have a ram air set up on it. I was asking because I assumed the ram air was added later. As mentioned, still a clean looking car on the top side and interior and I always appreciate a 4V 351C with a 4 speed and Trac-loc. Not sure about the floors though. I am thinking I will go see it before the auction if possible just because it went in the barn in 1987. Which is about 2 years before I bought my first Mach 1 that ended up with a similar paint scheme.

Can't tell from the picture, but does it have hood locks? If it does, the Ram Air was more than likely from the factory. Only factory Ram Air cars came with hood locks. While the hood locks could have been added after the fact along with the Ram Air, people usually don't go through the trouble of cutting up their hood.

I'd be all over that car, if I were you. A 4 speed M code is the next best thing to a 429 or a Boss, if you ask me. Do you have any better pictures you can share?

It does have the hood locks. So from what people are saying so far probably an original optioned ram air car? There is an appraisal document but no Marti report available.

Just leaving for work. Will post more pics tomorrow night.

I agree, great looking car. However, I suspect that Southern Ontario weather has not been kind to this one before and maybe even after it was stored in a drive shed. Looks great on top but perhaps a little "toasty" underneath. I need to go see it to be sure though.

I hope who ever does buy it will restore it and not part it out.

...While the hood locks could have been added after the fact along with the Ram Air, people usually don't go through the trouble of cutting up their hood...

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Be weary because I cut up my hood to add the hood locks when I added Ram Air. There's actually a center marking where to drill/cut the 3" holes from the underside, so it's not as daunting as it sounds.

Here an address for the description and photos on kijiji advertising the car in the auction:

http://www.kijiji.ca/v-classic-cars/guelph/auction-sale:-sat-june-6-at-10am/1073094276?enableSearchNavigationFlag=true

I skimmed this thread and saw a lot of mis-information.

Ram air was a factory option in 71.

A 4 speed car would have has a mandatory minimum 3.25 rear.

M Codes all had closed chambered heads. They were supposed to have 2 bolt mains but anything is possible and I have heard that some had 4 bolt mains but I doubt it was very many, if any, that actually came that way.

All Q codes have open chamber heads and 4 bolt mains.

M Codes had a square bore carb. Q codes had a spread bore carb.

That car, 1F05M179588, has some interesting options and in my opinion is factory correct except for the exhaust tips that are rotated toward each other. In my opinion the car is worth 10-12k IF there is no rust. Restored it is worth 25k or so.

FWIW I owned, restored and sold a 71 M code, 4 speed car that had a 3.25 rear and factory ram air.

Thanks to all for the info and ball park idea of value. I went to see the car today and have to admit I was wrong. On inspection, the car appears to in fact be a one owner 14,000 mile car which explains the original tires that piqued my interest in the beginning. However, seeing this particular car reminded me of the importance of prevention when storing my own cars. The car has been apparently sitting in the drive shed since 1987 and sitting in the drivers seat made me think I was sitting in a well maintained 2 or 3 year old car. The underside told a different story however. There is a lot of surface rust on the underside of the floors but no holes. While I assume with some wire brush work, a lot of paint or oil, all brake and fuel lines, fuel tank, brakes replaced and some work to bring a 28 year dormant engine to life, the car might safety, the floors are only going to make do for a limited time.

Not sure what it would have cost to oil/ rust proof that car from 1971 until it was parked in '87 and put a few layers of 6 mil plastic underneath but I suspect it would have added a lot to the value of the car.

Decisions, decisions... I haven't seen too many cars in Ontario that still have legible dealer instructions for removal of the tie down clips.

So what do you think, are going to make an offer?

..Not sure what it would have cost to oil/ rust proof that car from 1971 until it was parked in '87 and put a few layers of 6 mil plastic underneath but I suspect it would have added a lot to the value of the car...

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The primary thing would to be insure the car was super clean when stored, free of all debris, it looks like that one was parked with some road salt still on the undercarriage. Not sure about the plastic part, I think it would make matters worse by holding in condensation.

So did you make an offer or walk away?

I am seriously considering going to the auction this Saturday. However, given that the car looks "survivor" clean on the topside, the interior looks as new and that it is a one owner 14,000 mile car I don't think I have the pocket change to try. I will likely go to the Barrie ON Swap meet instead and try to buy some things for the cars I have already. Thanks to everyone for the knowledge of 71s they shared. If I find out how much it sells for I will let you know.