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Discussion Starter #1
So I have a 1999 F250 CC V10 it has a S5-47M Gas Units for a transmission and I have an adapter plate which is the same pattern as the T19. So I have the adapter plate figured out, but that is about it. I am looking to see if anyone knows of a flywheel to stick behind the cummins that will fit inside of the bell housing which is connected to the transmission and not removable. I have the flywheel that is from both application the chevy and the ford flyhwheel. They Chevy being 1.8 inches or so thick and the other much skinnier. Both are 14.75 inches wide including ring gear. Which is about .5 inches too big. Any ideas I am guessing that I have to use the thicker of the 2 flywheels but might have to have someone remove some material from the flywheel and maybe stick the original v10 ring gear on it.
 

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There is not adapter plate and flywheel combo to fit the ZF modular pattern transmission which is what you have. This issue has come up several times before. Destroked, who makes some of the best adapters only offers an auto trans mount for the modular. The smallest flywheel you will probably find is the small block Ford Cummins. Guys have used that with a modular pattern M5OD transmission and it worked. The T19 that came behind the 4bt would have been SB Ford pattern. That is not the same bolt pattern as the ZF modular. Some of the holes will line up, but several do not. That is unless you have one of the first gen modular engines that has the SB Ford bolt pattern. Then the transmission is the same as came behind the 5.8 engine and would bolt to the stock Cummins Ford adapter with no problems.
 

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Discussion Starter #3
So if I use the ford set up on the modular 5 speed and cut the flywheel down to 14.25 to fit into the bell housing then I should be good to go to run the Ford set up. So if the adapter plate bolts don't line up the spacing between the flywheel clutch basket will still be good to run?!
 

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If it will bolt up you shouldn't need to change the diameter of the flywheel. Have you actually put the adapter plate to the transmission to see how it aligns? Like I said, you could have the first production run of the modular which is identical to the SB Ford. Here's a couple photos of member Allisaw's build showing a modular M5OD mounted to the Ford Cummins adapter.
 

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You need to drill out and tap the holes for sae because the modular is metric, also I drilled out the two lower bell housing bolt holes and used a bolt and nut to make it work. In my build the it's a temporary setup until I convert to a ZF. As you can see from the photos there are some gaps. I've only put on 100ish miles running thi setup and so far so good
 

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I suspect the reason the adapter manufacturers don't design one for the modular is the lack of a flywheel. If there was a cheap, readily available supply of the SB Ford Cummins flywheel, then it would be fairly easy. Of course that might be a fairly small clutch to put behind a 6bt.
 

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Discussion Starter #7
Thank you for all the info. I will get some pics up soon. The adapter plate from the cummins to the zf5 speed fits just at in the picture above I think. The only problem is the flywheel being too big. A flywheel that is 14.75 is too big for the bell housing for the transmission. The adatper plate I believe is fine. The bolt holes in the bell housing is blocking the ring gear on the flywheel!
 

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That's strange that Allisaw's modular M5 fits the flywheel and the ZF modular doesn't. What diameter is your modular flywheel? Might take some doing, but I'm sure a custom flywheel could be made. Just need a machine shop that could turn and balance it. You could use the ring gear off a modular and hope the starter meshes with it. Of course if the flywheel gets smaller, then the starter gear won't engage. Then you'd need a custom adapter plate like one of the Destroked units.
 

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Taterchip, I believe you're going to find that the ring gear on the flywheel is totally inside the adapter housing. Only the flywheel body sticks out. You can see that in Allisaw's photo. Does that take care of the clearance issue?
 

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Taterchip, I believe you're going to find that the ring gear on the flywheel is totally inside the adapter housing. Only the flywheel body sticks out. You can see that in Allisaw's photo. Does that take care of the clearance issue?
The only way that I can think of as to how the flywheel could be located too far rearward into the bellhousing is if a spacer hub from an automatic transmission set up was still attached to the end of the crankshaft.

The adapter installs as a set as it was originally designed; adapter, starter and flywheel. You use the Ford/Borg Warner/T19 flywheel with the rest of the same "Ford" set. This is the thinner & lighter flywheel.

Maybe it is time to actually do a test fitting?
 

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Another thing, since you're dealing with a 6bt, you'll probably want to look for a heavier duty clutch assembly. The SB Ford is probably only a 10 1/2" where 6bt's ran 12 1/4" and 13". Might check with someone like South Bend to see what will fit that flywheel and give more holding power.
 

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My understanding is that the '99 V10 produces about 400 ft. # of torque...just like the stock 12-valve. Seems like the V10 clutch would be fine.

Am I missing something?

Roy
 

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My understanding is that the '99 V10 produces about 400 ft. # of torque...just like the stock 12-valve. Seems like the V10 clutch would be fine.

Am I missing something?

Roy
Yes.
The V10 makes its torque at 3250 rpm, the 12v Cummins is at 1500 rpm. The V10 has 5 power pulses per revolution, the I6 has 3. For the same output each pulse of the I6 is 1.65 times stronger. Low speed torque combined with fewer cylinders is a killer for weaker drive train components such as the clutch from a V10.
 

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Discussion Starter #17
Well this swap probably should not be on this site being that it is a 6bt. If anyone does not want it here I shall delete it. Otherwise it has been a battle! Originally from my research I was under the impression that I would be able to drop the cummins into the F-250 without using moving the transmission back. This is not the case. I am not sure if it is because of a not common transmission or what but I needed to move it back at least 2 inches to clear engine crossmember. So after considering a remote oil pan (dry sump) I said screw it and moved the transmission back 3 inches. It was pretty straight forward. Needed to first disconnect front and rear drive shaft then cut where the shifter is so it can move back further.
 

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Which year F250 are you dealing with? Also, the 6bt's had several different oil pans, depending on year and application. If your 6bt was a commercial engine, it has a bigger oil pan, where the late 90's Dodge has a smaller sump. That's the pan most people shoot for. No, we don't discriminate against 6bt's. There's a whole build section for them. Here's photo's of two of the oil pans. That may account for your clearance issue.
 

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Fixed your link for you. You should now be able to post links & pictures....
 
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