This thread ain't created to discuss merits ("just get a BTS"). Been working up a list of parts required to fit an Allison 1000/2000/2400 behind the 7.3 using International parts, and wanted to see if anyone had done it before in the Superduty trucks. Big question is will the SAE flywheel housing that attaches to the back of the engine fit without major clearance issues?

Another big question is flywheel balance. My engine is getting balanced with a Summit flexplate... I'm assuming that all the flywheels and flex plates for the T444E engine, be it in Ford or International application, use the same counter weighting? Given that there isn't different crank shaft or balancer part numbers for each application I'm assuming that flex plates/flywheels/spacers are all interchangeable and if I use the International parts to bolt up an Allison it shouldn't mess with the engine balance.

 

What does your machinist think about the balancing differences between the flex-plates? My assumption is that if the engine is balanced with a balanced flex plate, switching to another balanced flex plate should not matter. I mean, we do similar in zf6 swaps and all, light flex plate switched to heavy flywheel and a clutch, both of which are component balanced.
Interestingly enough, I had a customer call the other day with this exact same question, fresh engine and oem flex plate about to be balanced at machine shop. His machinist seemed to want the actual flex plate that would be used.

I guess I need to ask the engine/machinist guys at the other side of the shop to see what they think lol
I know one guy who has done the conversion with the sae2 bellhousing, he is a moderator on the 7.3 technical page facebook club, though I think his electronics and all are still from CA Conversions

 

He thought it'd throw everything off, but he's not well versed in these engines so I think he was assuming it would be a zero balance or weird aftermarket flexplate. Every 7.3 flex plate or fly wheel I've seen has a counter weight on one side. That weight distribution should be the same among all the variations to maintain cross compatibility... wouldn't make sense for International to use a different counterweight scheme vs Ford as that would mean different cranks, different harmonic balancers.

Haha that might have been a buddy of mine. I asked if he could give various places a call since I often don't have time during EST business hours. Or maybe this is gonna be the next hot 7.3 mod?

IIRC international only used a SAE 2 flywheel housing. SAE 2 transmissions hooked up directly, SAE 3 used a reducer ring. Same on the DT466. I'd definitely be interested in picking his brain if he's willing.

 

I was just about to mention him. I remember seeing his posts on that group with tons of pics and info.




If your on Facebook get on this group and search his name and you can see all his posts about it.

 

TOO BUKU!!!

 

I think the “proper” way to balance an externally balanced engine is with the parts you’re actually going to use. Yes each flexplate should all have the “same” counterweight but you know how production tolerances can be or how they can stack up. The engine builder is probably planning on getting it way closer to true balance compared to factory standards.

Not sure the slight variations in parts would be a big deal though on an engine that only turns 3400rpm.

 

My line of thought is, If I order a conplete kit from CA Conversions, there is nobody saying I have to pull my engine and balance it with the flexplate first, and they obviously wouldnt be selling them if they were going to damage engines.

I agree with JasonWV that the fresh engine at the builder may be to tighter tolerances, and can understand them wanting the actual flexplate to balance with it, so as to the the most perfected product balance

 

I wouldn’t give the balance any thought if buying a decent quality flexplate to replace one that’s already on there. In PriusLover’s case I would provide the flexplate to the machinist as he requested. If it gets changed later then no biggie in my opinion. These things live a million miles with just component balancing on factory tolerances.

 

This machinist is mostly in the high performance gas engine world where this would probably be a more pressing concern. Worst case scenario, if I do the conversion and notice a horrible vibration, I could potentially get the crank spacer counterweight modified to present a counterweight more similar to the 4R100 flexplate the engine was balanced with.



(No counterweight on the flex plate in the T444E application)

 

@PriusLover

Make sure you have good running condition engine first..
Then add all this cool stuff..

Balancing talk similar to turbo balancing(of course turbo shaft speeds in 100 000rpm+)but chasing for perfection calls a balanced assembly regardless the usage.

 

Definitely. The Allison talk is preliminary; the 4r100 in the truck now is dying so trying to see how feasible this path is. Would rather go with the 6 speed if I can keep the cost under control.

 

Assuming our factory flexplate has a counterweight, you would HAVE to use a flexplate with the same counterweight in the future. This is required for an externally balanced engine.

The machinist could possibly internally balance your engine which wouldn’t require counterweight on the flexplate or harmonic balancer. But that’s opening a whole other can of worms.

Point of my reply is, you cannot use the T444E flexplate as a direct bolt on option if it doesn’t have the counterweight balancing and the 7.3 flexplate does.

 

I will be watching this.

CA conversions wants stupid money like 12k and you install it yourself.

SAE2 bell housing and flex plate with a GM 6 speed Allison trans then there’s a guy that has a controller for Allison’s.

 

Where does a 6r140 fit into the mix?

6r140 with a manual shift transfer case that uses the factory floor shifter would be nice.

 

I do not think there are really any options for 6r140 mounting adaptors and electronics at this point in time