Time to restore

[AcesArneson]

I am in the planning stages for rebuilding my 73 Vert 351c -2V. Sending the motor out for rebuild to a shop that knows the engine and its oiling issues and knows how to fix them. I am looking for 450 hp from the engine and assume my FMX wont handle the torque and hp. I would like to know if anyone has another 4 speed auto they have fit in without modifying?

 

[Sheriff41]

About 15 years ago I retrofitted an AOD out of an 86 5.0 Mustang into my '72. I replaced the seals, put a in a 2300-2500 stall converter, and used a Lokar TV cable kit. A lot of people make a big deal out the TV pressure adjustment but it's really pretty straightforward and simple. I've had no problems to date. I don't track the car but do enjoy frequent "spirited" driving. Oh, and I run a 3.89 rear gear.

If I were to do it today I would look into an AODE/4R70W. If you use an AOD try to use one out of a late 80's to early 90's donor. The later AODs incorporated improvements by Ford. Also, I would probably go with a 3.50 or 3.70 gear, though the 3.89 is fun and at cruise in overdrive (4th) is about the same as the old 3.25/C6 combination.

 

[DAverkamp]

I am in the planning stages for rebuilding my 73 Vert 351c -2V. Sending the motor out for rebuild to a shop that knows the engine and its oiling issues and knows how to fix them. I am looking for 450 hp from the engine and assume my FMX wont handle the torque and hp. I would like to know if anyone has another 4 speed auto they have fit in without modifying?

Is your question that you think the FMX is a 4 speed or looking for an AOD that will drop in? The FMX if in good shape should handle what a 2V puts out to it or otherwise a C4 or C6 (also 3 speeds) are your other AT options with more strength and less weight. A 9" rearend is highly recommended if you don't have one as well.

 

[AcesArneson]

About 15 years ago I retrofitted an AOD out of an 86 5.0 Mustang into my '72. I replaced the seals, put a in a 2300-2500 stall converter, and used a Lokar TV cable kit. A lot of people make a big deal out the TV pressure adjustment but it's really pretty straightforward and simple. I've had no problems to date. I don't track the car but do enjoy frequent "spirited" driving. Oh, and I run a 3.89 rear gear.

If I were to do it today I would look into an AODE/4R70W. If you use an AOD try to use one out of a late 80's to early 90's donor. The later AODs incorporated improvements by Ford. Also, I would probably go with a 3.50 or 3.70 gear, though the 3.89 is fun and at cruise in overdrive (4th) is about the same as the old 3.25/C6 combination.

Thanks for the info, will a 4R70 fit without modifications? I have the stock 2.75's and I was thinking to take it up a bit to 3.00. I am in no need of raosting tires but do enjoy a really good sprint up to 120!

 

[AcesArneson]

Is your question that you think the FMX is a 4 speed or looking for an AOD that will drop in? The FMX if in good shape should handle what a 2V puts out to it or otherwise a C4 or C6 (also 3 speeds) are your other AT options with more strength and less weight. A 9" rearend is highly recommended if you don't have one as well.

Thanks, the 351C is going to breath pretty good. The rebuild is going to be pricy but it will push out just over 450 hp so the 3 speed FMX is going to be pushed to it's max if I keep it. I was just wondering if anyone else had tried an FMX with higher hp. My 73 has a 9" so I am good there, I think I will move up from 2.75's to 3.00's and convert the back breaks to disc with drum park break, Mustangsteve has a kit advertised with 13" discs on the back and 14" discs up front. Just waiting to hear back from him if he can ship them up North.

 

[jpaz]

You need more gear than a 3.00 with an AOD, at least a 3.50 - 3.70 with a 2500-2800 stall converter.

 

[will e]

Play around with this gear calculator.

Gear Ratio Calculator

It's one of the best around. It includes info and abilities for off road stuff with Transfer Cases etc but works great for street cars too.

I wanted to keep my already built C6 behind my Cleveland so I opted for a Gear Vendors overdrive. I am running 3.5 gears.

 

[Sheriff41]

Thanks for the info, will a 4R70 fit without modifications? I have the stock 2.75's and I was thinking to take it up a bit to 3.00. I am in no need of raosting tires but do enjoy a really good sprint up to 120!

From what I understand, the 4R70W retrofit is essentially the same as for the AOD with the exception of the ECU for the 4R70W and no TV cable. The ECU and evolutionary improvements are the big advantages of the AODE over the old AOD. Some of the Mustang suppliers offer retrofit kits with all you need for the swap.

Check out this write-up (even though it's on a 65 it'll be pretty close) https://www.vintage-mustang.com/thr...mplete-how-to-pic-heavy.1119498/#post-9747778

I agree with the others that the move from 2.75 to 3.00 wouldn't be worth the cost or effort. For a nice cruiser I think the 3.50 would be ideal, especially with your goal of 450HP. The Fox and SN95 Mustang communities preferred the 3.73 with the AOD/AODE in their cars.

 

[71ProjectJunk]

From what I understand, the 4R70W retrofit is essentially the same as for the AOD with the exception of the ECU for the 4R70W and no TV cable. The ECU and evolutionary improvements are the big advantages of the AODE over the old AOD. Some of the Mustang suppliers offer retrofit kits with all you need for the swap.

Check out this write-up (even though it's on a 65 it'll be pretty close) https://www.vintage-mustang.com/thr...mplete-how-to-pic-heavy.1119498/#post-9747778

I agree with the others that the move from 2.75 to 3.00 wouldn't be worth the cost or effort. For a nice cruiser I think the 3.50 would be ideal, especially with your goal of 450HP. The Fox and SN95 Mustang communities preferred the 3.73 with the AOD/AODE in their cars.

Agree going from 2.75 to 3.00 will make little to no difference, not worth the cost or effort to do it. 3.50 would be fine, but if you go with the overdrive transmission you can go for 3.70 gears.

 

[AcesArneson]

You need more gear than a 3.00 with an AOD, at least a 3.50 - 3.70 with a 2500-2800 stall converter.

You think so? Should be pretty close to 400hp at the wheels. Perhaps 3.25”s, the price of gas would have me sitting in the garage making screeching sounds behind the wheel like I did when I was 7.

 

[AcesArneson]

Thanks for all the advice guys, I am looking for a 4 r70 w to rebuild now and am thinking you might be right to go with 3.50s. Has anyone tried out MustangSteves 14” front and 13” rear disc conversion? Waiting for them to get back to me about shipping to Canada. Has anyone seen another adapter kit to use big brakes from other Mustangs like the 2005-19 that Steve offers?

 

[mrgmhale]

Thanks for the info, will a 4R70 fit without modifications? I have the stock 2.75's and I was thinking to take it up a bit to 3.00. I am in no need of raosting tires but do enjoy a really good sprint up to 120!

If you drop in an AOD, you can easily move down to 3.5:1 ratio rear axle gears and still be running just under 2,000 RPM with the engine at 60MPH in 4th OverDrive gear. You could even drop down to 4.11:1 and in OD still be turning only about 3,000 RPM at 60 MPH or so. Best of both worlds.

We replaced our 73 Mach 1 auto tranny with an AOD, and are running 3.5:1 TractionLok gears in the rear. I have attached some files with parts and vendor lists, and a list of YouTube videos we made covering the entire process. One of the videos covers how to splice the AOD NeutralSafety/Backup Lamp Switch into the older NSS/BUL switch harness.

I am very glad we did the transplant.

 

[AcesArneson]

Play around with this gear calculator.

Gear Ratio Calculator

It's one of the best around. It includes info and abilities for off road stuff with Transfer Cases etc but works great for street cars too.

I wanted to keep my already built C6 behind my Cleveland so I opted for a Gear Vendors overdrive. I am running 3.5 gears.

Thanks will e, that calculator has me convinced I can go to 3.5's. Really appreciate the share. We live 4 hours from everything so it will be on the hiway whenever we leave town with it, so 2100 rpm for 70 mph is more than acceptable and the 3.5's will allow me to have a little fun. It's been a long time since I was pulled over by the cops for any aggressive driving, hope it stays that way.

 

[AcesArneson]

If you drop in an AOD, you can easily move down to 3.5:1 ratio rear axle gears and still be running just under 2,000 RPM with the engine at 60MPH in 4th OverDrive gear. You could even drop down to 4.11:1 and in OD still be turning only about 3,000 RPM at 60 MPH or so. Best of both worlds.

We replaced our 73 Mach 1 auto tranny with an AOD, and are running 3.5:1 TractionLok gears in the rear. I have attached some files with parts and vendor lists, and a list of YouTube videos we made covering the entire process. One of the videos covers how to splice the AOD NeutralSafety/Backup Lamp Switch into the older NSS/BUL switch harness.

I am very glad we did the transplant.

Thanks mrgmhale, do you think you need the traction lock or does it have enough power to simulate a lock up? I would love to stick the 4.11's in but I will be doing too much hiway driving with it.

 

[71ProjectJunk]

Get a traction lock, if not that car will be doing the one wheel peel all day long. My car had a 3.25 open rear end, and I ordered and installed a 3.50 trac-loc 3rd member. I thought the engine was quite healthy with the 3.25 open rear as when I just touched the accelerator the car would immediately start peeling the tire. As soon as I put the 3.50 trac-loc I figured out how truly gutless this thing is, now I hit the go pedal and it just sticks and goes, no more wheel spin. I have to really punch it in first gear at about 3,000 rpm for it to now get some wheel spin. I used to just be driving around in first gear at a little over idle and if I just looked at the throttle the wrong way the one tire would start spinning. There is none of that now...

 

[mrgmhale]

If you have any kind of ability to spins the rear tires a TL gear set will help resolve it by having the torque split less unevenly as compared to an open gearing solutions. I find 3.5:1 to be a great compromise for spirited performance and highway driving.

 

[AcesArneson]

Get a traction lock, if not that car will be doing the one wheel peel all day long. My car had a 3.25 open rear end, and I ordered and installed a 3.50 trac-loc 3rd member. I thought the engine was quite healthy with the 3.25 open rear as when I just touched the accelerator the car would immediately start peeling the tire. As soon as I put the 3.50 trac-loc I figured out how truly gutless this thing is, now I hit the go pedal and it just sticks and goes, no more wheel spin. I have to really punch it in first gear at about 3,000 rpm for it to now get some wheel spin. I used to just be driving around in first gear at a little over idle and if I just looked at the throttle the wrong way the one tire would start spinning. There is none of that now...

Thanks Junk, I will definitely consider it.

 

[Mister 4x4]

You need more gear than a 3.00 with an AOD, at least a 3.50 - 3.70 with a 2500-2800 stall converter.

Ummm - No... you really don't.

My 351C-2V is pushing about 400hp (at the crank), and is backed with an AOD and factory 9-inch w/3.00s. The AOD came out of an '89 5.0 'Vert (which came from the factory with 2.75s. I received everything 'AOD' from the car, except the output yoke and TV/Throttle mount (since the guy still needed those for his 5-speed conversion). I adapted the AOD shifter to fit my '71, made a TV cable bracket using a Holley throttle cable bracket, and adjusted the FMX cross-member to fit the AOD's wider valve body/pan. The only other mods I had to do were using a 27 oz adapter flex plate, installing a hybrid VSS w/19-tooth speedometer gear, make an adapter harness for the Reverse Light/Neutral Safety Switch, and track down a conversion U-Joint (to fit the AOD yoke and '71 Driveshaft). Everything else was straightforward with the '89 factory components: torque converter, TV cable, shifter, et al).

The internal gear ratios of the AOD are identical to the FMX, except for having the final Overdrive gear. Since the AODs typically ran in front of 2.75-3.00 rear gears, it's just fine with factory equipment - I seem to remember 5.0 Mustangs being pretty quick back in the day. Since my engine's putting out significantly more power than it did from the factory, it has zero issues stepping out and getting to speed very quickly. I can boil the tires without much effort at all, and it only turns around 1800 rpms at highway speeds (just like my other, more modern cars - probably even gets around 18-19 mpg as well).

Am I going to win races with my set-up? HA!! Probably not even close... then again, I'm not trying to prove anything. I did once get the jump on a '20 5.0 GT, and he said he struggled to catch up, if that says anything (my buddy, actually). For the most part, everybody that lines up next to me at a red light seems to just give nods of approval and nobody has jumped off the line yet (late model Corvettes and Camaros, mostly). I think the Mach 1 reputation, engine note, and fat tires out back probably buy some respect.

 

[AcesArneson]

Ummm - No... you really don't.

My 351C-2V is pushing about 400hp (at the crank), and is backed with an AOD and factory 9-inch w/3.00s. The AOD came out of an '89 5.0 'Vert (which came from the factory with 2.75s. I received everything 'AOD' from the car, except the output yoke and TV/Throttle mount (since the guy still needed those for his 5-speed conversion). I adapted the AOD shifter to fit my '71, made a TV cable bracket using a Holley throttle cable bracket, and adjusted the FMX cross-member to fit the AOD's wider valve body/pan. The only other mods I had to do were using a 27 oz adapter flex plate, installing a hybrid VSS w/19-tooth speedometer gear, make an adapter harness for the Reverse Light/Neutral Safety Switch, and track down a conversion U-Joint (to fit the AOD yoke and '71 Driveshaft). Everything else was straightforward with the '89 factory components: torque converter, TV cable, shifter, et al).

The internal gear ratios of the AOD are identical to the FMX, except for having the final Overdrive gear. Since the AODs typically ran in front of 2.75-3.00 rear gears, it's just fine with factory equipment - I seem to remember 5.0 Mustangs being pretty quick back in the day. Since my engine's putting out significantly more power than it did from the factory, it has zero issues stepping out and getting to speed very quickly. I can boil the tires without much effort at all, and it only turns around 1800 rpms at highway speeds (just like my other, more modern cars - probably even gets around 18-19 mpg as well).

Am I going to win races with my set-up? HA!! Probably not even close... then again, I'm not trying to prove anything. I did once get the jump on a '20 5.0 GT, and he said he struggled to catch up, if that says anything (my buddy, actually). For the most part, everybody that lines up next to me at a red light seems to just give nods of approval and nobody has jumped off the line yet (late model Corvettes and Camaros, mostly). I think the Mach 1 reputation, engine note, and fat tires out back probably buy some respect.

Thanks for chiming in Mr. I am having difficulty tracking down the intake and heads I want and it is forcing me to look at the budget. CHI 208 heads look very good but very expensive. They would cost about 40% more than what I was looking for but will make it very easy to climb up into that 500 hp range. Perhaps I will compromise and go for the 3.25's?? I have a 4R75W lined up from an 09 interceptor to run with the cleveland. It's old and tired and needs to be rebuilt but I hear the can take a pounding if you do a good job on the rebuild so 500hp on a daily driver might be best to limit the rear ratio.

 

[Vinnie]

Hi,

In the coming years I'm going to have my own 351C 2V rebuild, may I ask what you are gonna do with your 2V engine to get it to put out 450HP?

Cheers,
Vincent.