A833 input shaft

[Tommy2turbos]

Has anyone had an issue with mating an A833 to a 383HP engine?

The input shaft seems to be too long and won't recess into the crank enough

Are there different size input shafts available for the A833? Has anyone machined out the crank to accept the longer input shaft? Has anyone machined the input shaft down to fit the crank?

Any advice/experience appreciated.

[Dave999]

sounds like you have a motor with a crank in it that was originally destined for an automatic
to save money they didn't machine the end of the crank for the bush.
or its machined but does not have the depth
or it is machinbed and just doesn't have a bush

if its a depth problem, it will need to be drilled deeper or the input shaft needs a hair cut
or if its deep enough but not big enough a hone may be the way to go. self centralises. you will be able to hone out a few thou

couple of ways around it

1) get a conversion bush.... which potentially involves machining the crank anyway, i think you can get em in standard size and a reduced size (OD) to cater for your problem. you might also need a touch off the end of the input shaft, they are hard.

2) chop a small section off the end of the input shaft and see if you can use the pilot bearing off a 90s dakota truck. https://www.rockauto.com/en/moreinfo.ph ... 4&jsn=1854
this is a holder and roller bearing that Press fit in the area normally taken up by the end of the coverter on a auto car
it is a press fit (block of wood and a mallet) into the HUB section of the crank that bolts to the flywheel. However this is a position about 1 inch further back than the stanard bush in crank set up, so you need to check if you can use it and not have the taper on the input shaft hit the roller bearing
or shim the bellhouisng back 1/8 or so, at the interface with the box usuing ARP hardend perfectly flat washers or an aluminium plate and use the same roller pilot, to be honest i'd do this rather than chop about an input shaft.


OR you have an a833 out of a chevy..... i.e one made by new venture rather than new process gear ... unlikley .... it wouldn't have the right bellhousing pattern.


here is a bunch of people talking about the same issue

https://board.moparts.org/ubbthreads/ub ... -size.html



Dave

[Blue]

Yes your engine has a crank not drilled for a manual trans. There is an input bearing that fits into the convertor snout drilling on the crank and you trim back the input shaft on the trans to suit. I had a new one of those bearings in my roll cab a while back, I'll see if I still have it.

[Blue]

Yep!

[Tommy2turbos]

Thanks for the info guys

I'll spend some time over the weekend taking a bunch of measurements (the battery in my vernier has packed up)
I knew it wouldn't be as straight forward as I hoped.
The bell housing mates to both the engine block and the gearbox independently. With the bell housing fitted to the engine, the input shaft slides into the crank so the OD appears to be fine. It looks like the recess in the crank is about 5/8 inch too shallow.

So just to verify:
1) the crank we can assume was supposed to be mounted to an automatic trans.
2) There's only one length of input shaft for the a833?
3) having the crank machined to fit the input shaft would be the ideal way to go.
4) trimming the input shaft is a possibility but will require shimming/bushing.

Blue, if I go the route of trimming the shaft back I'll be in touch about the bearing you have

[Dave999]

kind of

ideally if the engine was in bits you'd take crank and a new oilite bushing to an engineering shop and say stick that in there please level with the end.
or you take the attitude that the the hole is centralisd already. hone it to size OD of bushing, and then drill the area following the new bushing area deeper at a little over .75 to cater for a smidge of grease and the end of the spigot, knock in the new bushing ideally with a stepped rod 0.750 (maybe 0.746 to allow some compression) and slightly wider section to act as a shoulder to push in bush.
but thats a bit risky to do on the garage floor. Any misalignment leads to juddering clutch worn input bearing, and in worst case, creeping in neutral

however a simpler alternative is buy that roller set up off Blue, tap it into the converter snout area in the hub of the crank
cut 5/8s off the end of the rather long spigot on the end of the a833 input and be done with it. modern roller set up like a dodge magnum318 truck.

based on internet chatter it appears that there is enough space and it all works great.
i don't have an A833 so can't say for definite.
i am using a simlar set up for a Tremec t5 set up, yet to be fitted, to cater for too short input shaft.
i had mine ford sized shaft sleeved to mopor 0.750 size at the spigot so it fits the dodga dakota roller illustrated above

you are just doing what chrylser did in the 90s

the tranamission will now allways need to be used with this roller set up in any application.

5/8 is a bit much to shim back the trans, (if it was 1 or 2 8ths you'd get away with it) without checking where the stick goes through how much slot you have to use in the rear mounting (the holes often have a bit of space for adjustmnet), and how close the yoke is on the tail shaft to the back of the yoke seal, its a risk at 5/8 . if the seal is flat you may be ok, if it has a bellows to keep dust out the yoke may catch a rip it as the yoke moves in and out under suspension compression, both types work, orgionally i think they had the one with the bellows on


dave

[Blue]

I used one of those roller bearings on my 408 with a 833. I didn’t need to trim back the input but it would have worked fine if I’d needed to. No other shimming required and I think it’s a better set up than the old spigot bush knocked deep into the crank.