71-72 and pollution

[Machvince]

Hello

I'am trying to buy a Mach One (I leave in France...)

I found 71 and 72.. I have heard that the 71 (351) works better as in 72 there was a change for the regulation of the pollution.

Is there a real difference of power and pleasure between 71 and 72/73 ?

Any return of experience would be gladly appreciate. :thankyouyellow:

 

[Stanglover]

Hello

I'am trying to buy a Mach One (I leave in France...)

I found 71 and 72.. I have heard that the 71 (351) works better as in 72 there was a change for the regulation of the pollution.

Is there a real difference of power and pleasure between 71 and 72/73 ?

Any return of experience would be gladly appreciate. :thankyouyellow:

 Well, yes there is a big difference between 71 and 72, but are you talking 2V or 4V? 71's had higher compression for sure in both configurations. In this case it may come down to which CAR is best to restore. No sense buying a 71 for a better engine if the body is shot, unless it's a Boss or 429, which this isn't from your post.

Engines can always be rebuilt and upgrade to whatever you want. You might also want to consider the transmission, manual, C6 or FMX (I'm told FMX are junk)

Good luck and let us know what you decide,

Geoff

 

[Hemikiller]

In 72, cams had the timing retarded 4* or so for emissions. This did result in a loss in low end performance, but simply putting in a timing set with a 4* advance key will fix the cam issue. The 351CJ was unchanged from 71-72, except for the cam timing.

The big issue most see is the big drop in rated HP because of the switch from SAE gross (engine only) to SAE Net (engine with all accessories as installed). A good example is the 351-2V which went from a 240hp rating in 71 to 177hp in '72. The CJ engine dropped only from 280 to 266 in '72, which demonstrates how underrated these engines were.

FWIW, the FMX is not "junk", but it is an older design with limited parts support compared to the more popular C-4 & C-6.

 

[73pony]

+1 on finding the car itself in the best condition then making the drivetrain what you want. Also no reason to avoid the FMX. While support is more limited you can still get shift kits etc for them and they will hold up to a significant amount of power.

 

[Fabrice]

Regarding the FMX, I would certainly argue the first above statement. At least for street use, not in race situation.

The C6 can for sure take more punition and was used behind the 71 torque monster 429 for a reason but an FMX that is maintained properly handles a very healthy 351 4V without a hitch. Mine with an 11 inch 2.5 stall converter never complained while my tires did.

As you are in France, I'd say, try to find one that is not missing too much parts and in best body condition as possible. Any of the offered engines once restored/prepped can be much more performant than the "original" specs that you will find.

Unlike our US friends, know that each part you will need to order (and you will need a lot over the years) will cost you most of the time twice the price that you see online once at your door and for the bigger/heavy ones, many times more.

if its your first "classic" car and you plan do it yourself, you will also need to invest in good tools.

Bonne chasse!

 

[Carolina_Mountain_Mustangs]

As many have stated the body condition if more important than engine or year. A great rust free, never painted body is much better than a shiny skim coated bondo filled body that is eaten up with rust. If you look at a M code, Q code and H code 351 C the block and crankshaft are all the same. Yes H code is 2 bolt but can be machined to accept 4 bolt. You can put any head you want 2-V, Closed Chamber, Australian, aftermarket aluminum lots of choices. With the fuel you have available that will determine how you build the engine unless you have a large budget for expensive fuel.

Look for a car that has documentation of how it came from factory, the options you want and as rust free as possible. If it has been painted ask for pictures of the body before paint. If they will not supply them then they are probably hiding something. Every 71 - 73 will have some amount of rust in the cowl and around the tail lights. Bare metal rusts and its was bare metal in those areas due to poor paint and sealer application.

If you do find something that is located in my area I would be willing to go do an in person inspection of the car. Take your time searching more and more come to the market each day as the old timers like me die off. I am in North Carolina there are lots of Mustangs here and in Georgia for sure. They will have rust.

On another side of the coin. If you get a car from the South Western U.S. or California then you can count on the interior having been baked by the sun. They will have rust also from the owner just washing the car. I find much better interior panels in the North Eastern U.S. but they are usually eaten up with rust due to so much salt on the roads in the winter.

Never trust the seller to tell you the truth. You have to do an onsite inspection or you will not know what you are getting. Pictures do lie no matter how many or how clear the owner can hide the bad places.

 

[Machvince]

Thanks all,

So as I understand : i have to prefer a car with a good body, than be sticked on one year. Car from the west have nice bodies, but interior burned and car from the east have nice interiors.. (to be very very quick).

Well it's a good news for me, I do not have to be glued to one year..

David, thanks for the check list, and for the idea of seeing the car, I appreciate.

 

[Stanglover]

Oh sh*t, looks like I opened a can of worms with the FMX in brackets statement. That's just what I was told from someone who has one and hates it.... for many reasons, or so I'm told.

 Personally it's manual or nothing for me, but who knows one day I might be too old a weak to handle a heavy 11" clutch, then I would go for the C6!

 Geoff.

 

[Fabrice]

Oh sh*t, looks like I opened a can of worms with the FMX in brackets statement. That's just what I was told from someone who has one and hates it.... for many reasons, or so I'm told.

ahahaha, yes you did

Thing is, the frustration when something doesn't work is often black and white. Last year for instance, when I've installed my EFI, I needed go around the lack of KD support on the Holley Sniper. Practically on all forums, as the missing KD support is also common on carbs, the "best" alternative that is promoted is the FMX lockar cable kit. While the cable on itself is indeed of a great quality and finish, the bracket that they provide is a bad joke and will never even lead to a properly functioning KD. I'm convinced Lockar never actually installed their product at least once on an FMX. You then read on many forums how hard this cable kit is to get it right. You see horror picts with this cable kit hanging around doing nothing or too much. This is a detail of course and there are surely other issues due to the FMX design on certain combos, but when you know how popular that kit is and how sensitive this trans is on vacuum and the KD to function properly, just like its grand son the AOD. You know there are tons of people running an FMX with this kit not operating as it should, the trans eventually gets a bad name.

 

[Stanglover]

Oh sh*t, looks like I opened a can of worms with the FMX in brackets statement. That's just what I was told from someone who has one and hates it.... for many reasons, or so I'm told.

ahahaha, yes you did

Thing is, the frustration when something doesn't work is often black and white. Last year for instance, when I've installed my EFI, I needed go around the lack of KD support on the Holley Sniper. Practically on all forums, as the missing KD support is also common on carbs, the "best" alternative that is promoted is the FMX lockar cable kit. While the cable on itself is indeed of a great quality and finish, the bracket that they provide is a bad joke and will never even lead to a properly functioning KD. I'm convinced Lockar never actually installed their product at least once on an FMX. You then read on many forums how hard this cable kit is to get it right. You see horror picts with this cable kit hanging around doing nothing or too much. This is a detail of course and there are surely other issues due to the FMX design on certain combos, but when you know how popular that kit is and how sensitive this trans is on vacuum and the KD to function properly, just like its grand son the AOD. You know there are tons of people running an FMX with this kit not operating as it should, the trans eventually gets a bad name.

 Fabrice, that's a very interesting write-up. Not being an Auto Trans guy, I have zero knowledge of the issues around them. but your comments should be helpful to others. I will pass this on to the person I know of who is having all sorts of problems with his FMX. I know a lot of his issue is internal, but all could be related without him knowing or fully understanding. I guess sometimes a misspoken (or written) statement CAN be a good thing in the end.

Thanks for the comments.

Geoff.

 

[Fabrice]

 Fabrice, that's a very interesting write-up. Not being an Auto Trans guy, I have zero knowledge of the issues around them. but your comments should be helpful to others. I will pass this on to the person I know of who is having all sorts of problems with his FMX. I know a lot of his issue is internal, but all could be related without him knowing or fully understanding. I guess sometimes a misspoken (or written) statement CAN be a good thing in the end.

Thanks for the comments.

Geoff.

For the record, I gave this example just to illustrate how black and white people can be and easily blame the original piece of tech. Not saying its THE fmx problem! Like with engines tons can go wrong and your friend can have a defective one or just dislike it vs a c6.

I was just shocked at how many use that thing out of the box without questioning for a sec what they've actually installed.

Over the years I've met lots people that never checked or even knew how to properly fill their trans and with what. Its very often just the big thing behind the engine that is expected to do whatever that thing does and expected to never fail.