5.9 Magnum 5-speed In an early A??

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xLURKxDOGx

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I saw a truck 5 speed at the junkyard and it got me wondering if this swap is possible and if so what sort of trouble is it going to be???


Thanks,
Jake
 
I thin it requires trans tunnel and trans crossmember mod. Someone will pipe up, but I think I have seen tis discussed before regarding the early a.
 
I thin it requires trans tunnel and trans crossmember mod. Someone will pipe up, but I think I have seen tis discussed before regarding the early a.

Thanks! I searched the forum and didnt see anything regarding the 5 speed, ill have another look.

Jake
 
Thanks! I searched the forum and didnt see anything regarding the 5 speed, ill have another look.

Jake

Try searching on "AX15" or "NV3500" for a truck 5 speed.

75Slant6 put an AX15 in his Duster. Not an early A, but might be helpful. My Duster Adventures

I know there is at least one other that did it as well.

If you search on "R154", you might find more info as well. I started swapping an R154 into my '63 Valiant and there are some pictures online of what I did, but I will let you find them. Never completed it, car was too rusty.

Yea what rear gears would you run to be simliar to like a 3.55 through a tourqueflight?

You would have to run something like a 2.27 rear end gear to simulate a 727/3.55 setup. But that ignores the torque multiplication in the auto. Running a 2.93 rear gear with an AX15 would be like a 4.56/727 combo.
 
Just to flesh it out a little better, while that AX15 has a deep first gear (3.83:1), with a .271 final drive it wouldn't be any worse than a standard 4 speed with 4.10 gears. The 2.66 first gear 4 speed would have an overall ratio of 10.91 while the AX15 would bee 10.38.

And the ratio splits are actually better than an A833OD at 39% 1-2 and 38% 2-3 for AX15 versus 46% 1-2 and 40% 2-3 for the A833OD.

So, while the AX15 might be geared pretty deep and far from ideal, it might still be better than some other options.
 
I believe this is a NV3500
Those gear-spreads are set up for a truck; not very good for a streeter. Low is much to low.
4.02-2.32-1.40-1.00-.73
The 1-2 split is 57.7%. What that means is when you typically out-shift first at 2800 ish, it drops into second at about 1600; so your engine better be able to pull at that rpm. Typically a performance engine kindof plays dead down there. So if your engine doesn't wake up until 2200, then first will have to wind up to 2200/.577=3800. Do you really want to wind it up that high in first nearly every time you go out.
Oh, and 2-3 ain't much better at 60.3%.
The 3-4 is pretty good at 71.4%
And overdrive is too close at 73%
This tranny works very well in it's original configuration, behind a torquey low-rpm engine.

I guess you could kindof make it work with say 3.55s, cuz then your starter would be 14.27, and second would be a kindof normal 8.23. But now 3rd is still out there. Still 3000 in second is almost 30 mph so you are kindof looking to merge with traffic anyway so into third it goes and you are cruising at 1800ish. While that is by itself prettygood.But your average LA performance teener hasn't got a lot of pull down there, so if you are heading out on the highway, you might have to keep in second until 4000, to drop into third at 2400. Oh, that hurts. So now you are at 2400 in third at 39mph, and it's still a long way to 65. But let's continue. The next gear is a little closer so unless you are driving a brick, lets shift a lil sooner, say 3700. Now you will enter 4th at 2700, a reasonable rpm, and you are moving at just about 60mph, Oh man, so close. 65 in 4th will be 2867, just 167 rpm, to go 6 mph.Kindof a short gear there,eh
So now you arrive at 65 and stuff it into o/d, and the Rs drop to 2035. Well surprise,surprise, that's the perfect cruiser gear for an LA teener! But notice that fourth was kindof a wasted gear.
If you swap in a different rear gear, to actually use that 4th gear (I mean you might as well use it if you got it, right?), you will find that 4.30s about covers it. These will get you 65@3472; and o/d will drop that to2465, still doable. But what happens at the other end? You guessed it the starter gear is now 17.29;a totally useless granny-gear. Second is now 9.98 a very nice teener starter gear.
No, 3.55s are the right rear-gear to run; the ratio spreads are just too far apart for an A-body V8.
Unless you need a crawler gear where 644rpm is 3mph. This is actually a good parade gear! Now you can hang with the automatics and have a clutch left when the parade is over.lol

OK so, wait! There is a Dakota version with a bit better gearing;
3.49-2.14-1.38-1.00-.73o/d with splits of .61-.64-.72-.73.
This is a bit better. But you are still gonna have to rev first to 3600 to catch second at 2200, and to 3438 to catch third at 2200, and to 3055 to catch fourth at 2200, and to 3014 to drop into o/d at 2200=68mph with 3.55s, and 27" tires.
And 3.55s will get you a nice 12.39 starter gear.
So build your teener to make some oats at 2200 and you will have some fun.

Hey, I might get me one of these, and put it behind a 273! But I think I'll use 3.23s or maybe 2.94s. Hyup, 2.94s will still get me a 10.26 starter, and a hi-way gear of 2.146;oh yeah!; mpgs here we come! 62@1652
I'm starting to like this closer ratio one!
 
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Major cutting, and a pretty wide ratio spread between gears.

Try searching on "AX15" or "NV3500" for a truck 5 speed.

75Slant6 put an AX15 in his Duster. Not an early A, but might be helpful. My Duster Adventures

I know there is at least one other that did it as well.

If you search on "R154", you might find more info as well. I started swapping an R154 into my '63 Valiant and there are some pictures online of what I did, but I will let you find them. Never completed it, car was too rusty.



You would have to run something like a 2.27 rear end gear to simulate a 727/3.55 setup. But that ignores the torque multiplication in the auto. Running a 2.93 rear gear with an AX15 would be like a 4.56/727 combo.

I believe this is a NV3500
Those gear-spreads are set up for a truck; not very good for a streeter. Low is much to low.
4.02-2.32-1.40-1.00-.73
The 1-2 split is 57.7%. What that means is when you typically out-shift first at 2800 ish, it drops into second at about 1600; so your engine better be able to pull at that rpm. Typically a performance engine kindof plays dead down there. So if your engine doesn't wake up until 2200, then first will have to wind up to 2200/.577=3800. Do you really want to wind it up that high in first nearly every time you go out.
Oh, and 2-3 ain't much better at 60.3%.
The 3-4 is pretty good at 71.4%
And overdrive is too close at 73%
This tranny works very well in it's original configuration, behind a torquey low-rpm engine.

I guess you could kindof make it work with say 3.55s, cuz then your starter would be 14.27, and second would be a kindof normal 8.23. But now 3rd is still out there. Still 3000 in second is almost 30 mph so you are kindof looking to merge with traffic anyway so into third it goes and you are cruising at 1800ish. While that is by itself prettygood.But your average LA performance teener hasn't got a lot of pull down there, so if you are heading out on the highway, you might have to keep in second until 4000, to drop into third at 2400. Oh, that hurts. So now you are at 2400 in third at 39mph, and it's still a long way to 65. But let's continue. The next gear is a little closer so unless you are driving a brick, lets shift a lil sooner, say 3700. Now you will enter 4th at 2700, a reasonable rpm, and you are moving at just about 60mph, Oh man, so close. 65 in 4th will be 2867, just 167 rpm, to go 6 mph.Kindof a short gear there,eh
So now you arrive at 65 and stuff it into o/d, and the Rs drop to 2035. Well surprise,surprise, that's the perfect cruiser gear for an LA teener! But notice that fourth was kindof a wasted gear.
If you swap in a different rear gear, to actually use that 4th gear (I mean you might as well use it if you got it, right?), you will find that 4.30s about covers it. These will get you 65@3472; and o/d will drop that to2465, still doable. But what happens at the other end? You guessed it the starter gear is now 17.29;a totally useless granny-gear. Second is now 9.98 a very nice teener starter gear.
No, 3.55s are the right rear-gear to run; the ratio spreads are just too far apart for an A-body V8.
Unless you need a crawler gear where 644rpm is 3mph. This is actually a good parade gear! Now you can hang with the automatics and have a clutch left when the parade is over.lol

OK so, wait! There is a Dakota version with a bit better gearing;
3.49-2.14-1.38-1.00-.73o/d with splits of .61-.64-.72-.73.
This is a bit better. But you are still gonna have to rev first to 3600 to catch second at 2200, and to 3438 to catch third at 2200, and to 3055 to catch fourth at 2200, and to 3014 to drop into o/d at 2200=68mph with 3.55s, and 27" tires.
And 3.55s will get you a nice 12.39 starter gear.
So build your teener to make some oats at 2200 and you will have some fun.

Hey, I might get me one of these, and put it behind a 273! But I think I'll use 3.23s or maybe 2.94s. Hyup, 2.94s will still get me a 10.26 starter, and a hi-way gear of 2.146;oh yeah!; mpgs here we come! 62@1652
I'm starting to like this closer ratio one!

Thanks for all the replies, i guess its not worth it then. There's a local ball and trunion 4-speed but i think i read something about the odd first gear?? Anyhow, i have a rebuilt 904 so no biggie but enjoy driving the 5 speed i have in another vehicle.

Jake
 
The old ball and trunion trans will probably have a 3:09 1st gear, and could work ok other than the obvious driveshaft issue
 
Thanks for all the replies, i guess its not worth it then. There's a local ball and trunion 4-speed but i think i read something about the odd first gear?? Anyhow, i have a rebuilt 904 so no biggie but enjoy driving the 5 speed i have in another vehicle.

Jake
I gotta disagree with it not being worth it. But that's just my opinion. Like Dion said, I swapped an AX-15 from a 98 Dakota into my Duster. Currently with 3.23 gears and a 275/35/17 rear tire first gear is pretty well useless if you're taking off on a flat surface but this winter I'll be swapping in 2.76s and it'll be a much better setup. Here's a picture of the comparison of an ax-15 with 2.76s and a low first gear 904 and 4.10s. Notice how 1st-3rd are nearly identical plus you get 2 more gears and OD
image.jpg

Ralphie361 has also done and AX-15 swap in his Dart and he put 2.76s in and said the car is much better to drive.
 
I have been running the 3.09 low since around 2004, and I love it. It's perfect for sbms on the street, with just about any cam, but especially with mild to moderate cams up to say 230* @050.
This makes the ratios 3.09-1.92-1.40-1.00 and the splits .62-.73-.71. My small cam 367 easily pulls the 1-2 split with 3.55s,even short-shifting;and then things are normal.
 
Which is still better than an A833OD which is 54% using your method. Correct? :)

You are quoting the A833 o/d box. It has ratios of 3.09-1.67-1.00-.71o/d, splits of 54-60-.71
And yes it is terrible for a performance street sbm with anything more than a stock teener cam. I ran that ratio with a GearVendor's splitter behind it. The new ratios where 3.09-2.41-1.67-1.30-1.00-.78-.55 with splits of .78-.69-.78-.77-.78-.71 Saweeeet.(GV ratios and splits in red)This was awesome with a small cam, keeping the engine on the pipe from the get go to gone! But it wasn't that streetable. With 4.30s first was all but useless,The final drive of 2.37 was nice. 3.55s made streetability ok. But I just got tired of splitting gears all the time, cuz the splits in the main box were just not street friendly, with even the 223* cam I had in it at the time..The 3.09 box solved all that. I still run the GV behind it, to turn the 3.55s to2.77s for the hi-way. 3.09-1.92-1.40-1.09-.78 with splits of .62-.73-.78-.71. nice progressively decreasing splits.That's the way;unhuh,unhuh.
But Ima still digging the close ratio NV above.I wonder how long it would endure 400 ftlbs?
 
You are quoting the A833 o/d box.

Correct, which is why I referenced it in my post. :poke:

My only point was that plenty of people run around using an A833OD without a GV, and seem ok with it. An AX15 with a slightly better split wouldn't be any worse. I myself run an A833OD with a 2.71 rear gear ratio (long story) behind my cheap copy of a 300hp 360 crate motor. It could be better, but it is far from undrivable, and even enjoyable.

But Ima still digging the close ratio NV above.I wonder how long it would endure 400 ftlbs?

Per Wikipedia (if it can be trusted) the close ratio NV3500 is rated at 340ft/lbs. I bet it would live just fine.

Just so you are aware, it is an integral bell housing transmission, unlike the AX15/MA5/AR5/R154 style trans. Don't see that it matters, still bolts up to a SBM, just pointing it out.
 
Just so you are aware, it is an integral bell housing transmission, unlike the AX15/MA5/AR5/R154 style trans. Don't see that it matters, still bolts up to a SBM, just pointing it out.
The AX15 may as well be an integral bellhousing trans since you have to pull the entire transmission in order to remove the bell; the bolts are inside the bellhousing! :wtf::BangHead:
 
The AX15 may as well be an integral bellhousing trans since you have to pull the entire transmission in order to remove the bell; the bolts are inside the bellhousing! :wtf::BangHead:

Yeah, I agree. Only pointed it out because it means you couldn't swap the bellhousing if needed, but since the only bellhousing that works is a stock Dakota one, it really is a useless difference. The NV3500 already bolts up to a SBM, so no good reason to want to swap it, other than the fact you are forced into a 143T flywheel, and the only fix I am aware of for that is to relocate the starter pocket.

Hey, what program did you use above to calculate the speeds between the AX15 and 904?

Doh
I missed the reference,sorry. Now quit poking me,already,lol

:thumbsup:
 
Yeah, I agree. Only pointed it out because it means you couldn't swap the bellhousing if needed, but since the only bellhousing that works is a stock Dakota one, it really is a useless difference. The NV3500 already bolts up to a SBM, so no good reason to want to swap it, other than the fact you are forced into a 143T flywheel, and the only fix I am aware of for that is to relocate the starter pocket.

Hey, what program did you use above to calculate the speeds between the AX15 and 904?



:thumbsup:
Here you go.

Gear speed calculator

DISCLAIMER: I am in no way, shape or form into or involved with the JDM community, I just googled gear speed calculators a year or more back and that was the one I liked the best.
 
Got it, thanks for the write up! Let me know how it goes and if you have any pics to share that would be great as well.

Jake
 
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