Has anybody put or seen a 460 with a six speed on a late 80's 3/4 ton pickup?

 

There are only two six speeds that I know of... the ZF S6-650 for the newer super duty bell housing patterns, which won't fit the 460's bellhousing, and the NV5660 found in cummins powered trucks, which also isn't a bolt in.

You need to make, or buy, an adaptor. I'm sure someone has, maybe a little googling for "460 NV5660" might give you a few decent hits. I had searched a few months ago and got pages and pages of mis-hits however...

 

think of how fast that 460 would be with the 6 speed........i've contemplated this swap for a long time.

i'm sure you could modify a 460 bell housingto fit into the ZF-S6-650

 

I too would love to have the 6-speed in my truck. somone needs to figure out how to make it work, My tranny needs to be rebuilt and I would rather spend the money on a 6-speed.

 

This is something that I am interested in also. The zf 6speed would be a natural match for the 460.

 

Dynatrac was working on an adapter/bellhousing for the NV 6 speed to fit gas motors. The owner has a nice 460 powered '78 F-250 that he was doing the swap on. There was even a write up in one of the offroad mags, If I recall they had it all worked out and everything I am sure it will be extremely expensive for the trans/adapter and misc stuff,not real cost efective but can be done. Dynatrac is on the web and in mags so call em up and ask.

 

Fellas,
I have wondered about this for a while myself. The ZF-S6-650 is an awsome trans. It was available with the 7.3 PS for a few years until the 6.0 replaced it. What is the bellhousing pattern on the 7.3 PS ??? I think the 7.3 PS has the same bellhousing pattern as all of the gas truck engines. I don't have a 7.3 6speed truck available to look at, but there might be an adaptor or maybe there is a few S6-650's with a different bellhousing.

 

Hey,
I am not positive but don't all of the ZF trannys have an integral(SP?) bellhousing?
meaning that the bell housing is not removeable but part of the trans case? I may be wrong just seems that is what I had heard.

 

Yes, I believe they do have an integrated bellhousing.

 

yes, ZF's have integral bell housings.

I've made adapters before, just not for this combination, and it's not impossible to do at home. I made a Porsche 944 transaxle to a Buick V6 using this method and got it correct the first try.

First, measure the diameter of the input shaft on the old transmission, then measure the diameter of the new transmission. Whichever one is smaller, drill that hole in the center of a large square or 3/8" plate. Put this plate across your sawhorses, then stick the transmission with the smaller diameter input shaft on top of the plate, input shaft through the hole you drilled, facing down. Then mark the transmission's bell housing pattern both in external shape/dimension with a sharpie, as well as the bolt holes.

If the transmission with the smaller input shaft is the original transmission, then drill the holes out cleanly to match the bolts of the 460. If the transmission with the smaller input shaft is the new transmission, drill the holes undersized and tap them to match the bolts you'll use to attach the transmission to the plate.

Then take the transmission with the larger diameter input shaft, enlarge the hole in the center of the plate to that dimension, then slip that transmission through the hole and line it up the best you can. You might have to angle the transmission very slightly, so the ears of this transmission don't line up with the holes you've already drilled. A small angle on a manual transmission to either side is not a big deal, if its only a few degrees. Do note that your shifter will move that same amount however, but you can fix that by heating the shifter shaft with a torch, and bending it slightly.

Anyway, mark those holes, and trace the outside pattern with a different color sharpie. If the transmission with the larger input shaft is the original transmission, then drill the holes out cleanly to match the bolts of the 460. If the transmission with the larger input shaft is the new transmission, drill the holes undersized and tap them to match the bolts you'll use to attach the transmission to the plate.

Now comes the fun part - whittling out the center and the excess "wings". You've marked up the outside of both transmissions, and you can cut this out easily using an air saw, a sabre saw (if you go very slow), or even better a plasma cutter. Make sure at all times, you cut only on the outmost lines, regardless of which transmission the lines came from. You need to make sure of this, because cutting too far in will result in you starting over. If you want to be cautious, just cut a big arc around the whole thing, leaving at least 1/2" around the sharpie lines. You can adjust the shape later with an angle grinder or any of the tools I mentioned above if it interefers with the firewall, for example.

Cutting out the inside is a little tougher... take the 460 flywheel and center its hole over the center hole in the plate. This is where you need to be careful, and make sure its centered. Tap it gently to move it around, until its lined up where you want it, then trace that with a different color sharpie around its perimeter. Don't worry about the circle (arc, really) being perfect as the teeth of the flywheel will make for a slightly jagged tracing. Now that you have your arc, cut that out on the outside of the line. Put the flywheel back on the engine, put your adaptor on the back of the block, and see if it clears the flywheel. If you've been careful, it should clear. You might have a little dremeling or angle grinding to do, but it should be minor.

I successfully mated several odd combinations of engine/transmission this way, including a RWD Buick V6 to a Porsche 944 transaxle, a Rover V8 to a Porsche G52 transaxle, and a FWD Buick V6 to an Audi Quattro transaxle.

I've always welded on after-the-fact a portion of the scrap 3/8" plate that I've hacked up to mount the starter, welding it to the adaptor I just made. I can't seem to line up the starters correctly making the template with the bell housing adaptor as one piece... maybe you'll be more clever than I and be able to do that correctly. I unfortunately never got it right. But, nothing a mig welder can't fix easily enough.

Hope this was at least interesting...

 

frederic,
Nice post. I have often thought of what you explained. I never had to do it. How do you compensate for the extra 3/8" at the pilot bearing. Also do you know anything about the 7.3 PS with a ZF-S6-650. This would be ideal because the shifter and the t-case and it's shifter bracket might fit the earlier trucks without much trouble. Thanks.

 

Well, think about what a pilot bearing really is - its a chunk of bronze machined to look like a donut. Any machine shop can make one, or if you have one of those Grizzly 7x10 mini lathes you can make one yourself. All you need is a boring bar and an accurate caliper. A pilot bearing can be made out of anything actually, as long as its softer than the input shaft which most everything is because the input shaft better be hardened and heat treated steel - otherwise with 650 ft/lbs of torque twisting it, it snaps. So bronze is what most manufacturers use and I've even used 6061 aluminum before when it was convienent.

You drill the inside smaller a smaller amount than necesary, then use a boring bar to enlarge it. If the shaft is tapered, instead of a boring bar you use a reamer. Then you chuck the thing and turn the outside down.

Just make it 3/8" longer than stock

Most input shafts hang into the crank more than the factory pilot bearing is wide, so having it stick out a little doesn't hurt anything. All that matters is that some of the input shaft actually is inside the crank flange.

I am not a powerstroke guru, however for my eventual twin turbo 500cid crewcab, I very much wanted the S6-650 tranny, however I couldn't find one at a reasonable price, so I ended up with a lucky find of a 40K BBF ZF for $350, with two hydraulic PTO's on both sides. Sold one for $350 on ebay, so now the transmission cost me exactly zero. So, I didn't research to see if some, or any, of the bolt holes line up with the 460. Someone years ago told me that the top two do, however I find that hard to believe. Nothing every lines up nicely.

When I made the plate for the Audi / FWD Buick V6 combination, I had to tilt the tranny six degrees to one side. After thinking about it for a while, because it's a transaxle and not a transmission, I had to worry about half-shaft angles as well, so I mounted the transmission level to the suspension, and tilted the engine six degrees. They're tilted backwards in FWD GM cars anyway, so I didn't see the harm in it at all. I verified the pickup tube in the oil pan which is on one side, was on the "down" side of the tilt so it was always submerged. Would have sucked if it was on the "up" side of the tilt!

The reason why I typically use 3/8" mild steel plate is that its thick enough to tap, yet not too thick to cause silly pilot bearing problems. Different combinations of engine/tranny might require a thinner plate, and that's tough to do correctly. I'd worry about the tranny bolts pulling out of 1/4" plate...

Another option is to make a 3/8" spacer on the back fo the crankshaft, but definately have a machine shop grind it absolutely flat on both sides, otherwise you might have a wobbly flywheel which will be disasterous for the clutch at a minimum. That's worth paying for.

 

cool description of the process.. I might try this..

now, how do you deal with an auto tranny.. what is a good solid spacer at the convert bolts?

thanks

Sam

 

I've never made an adapter for automatics... but I imagine its essentially the same thing. 3/8" adapter, 3/8" spacer between the TC and the crank tail. Make the spacer out of 7/16" thick steel and have a machine shop grind it flat both sides so its 3/8" and both sides are absolutely parallel.

Automatic tranny input shafts stick out past the edge of the bellhousing, correct? That's what's necessary to use my method.

If it doesn't, then you have a fun time of accurately measuring the x/y coordinates of the centers of each hole and the input shaft on the tranny. If this is the case, I'd just borrow a manual tranny from a friend, make the adapter as I outlined above, and return the tranny with a case of beer to said friend

I hate measuring...

 

Try Advanced Adapters, they make adapter plates for tons of engine tranny combos.