C8 Transmission

B

bd5av8r

New member
Aug 25, 2010
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Musing out loud:

Would the new C8 (2020 Corvette - mid engine) transmission be an excellent
replacement for the GMC (in an effort to get modern multi-speed gearing to
improve gas mileage and cruise RPMs) It so far looks promising. Such a
trans could be fit to the GMC with an adapter-- or if using a Chevy engine
possibly go in with mods.

Sammy Williams
 
Wouldn't the engine end up in front of the axle shafts? Seems like it would be popping out the grill but I could be missing something.
--
Todd Snyder, Buffalo NY
1976 Eleganza II
 
You would use a transfer case and put in a axle assembly.

On Wed, Jul 31, 2019 at 7:39 PM Todd Snyder via Gmclist <

> Wouldn't the engine end up in front of the axle shafts? Seems like it
> would be popping out the grill but I could be missing something.
> --
> Todd Snyder, Buffalo NY
> 1976 Eleganza II
>
> _______________________________________________
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>

--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
I would love to have the gear ratios or even a 2-speed final drive to go
with what we have now.

On Wed, Jul 31, 2019 at 7:47 PM Jim Kanomata via Gmclist <

> You would use a transfer case and put in a axle assembly.
>
> On Wed, Jul 31, 2019 at 7:39 PM Todd Snyder via Gmclist <

>
> > Wouldn't the engine end up in front of the axle shafts? Seems like it
> > would be popping out the grill but I could be missing something.
> > --
> > Todd Snyder, Buffalo NY
> > 1976 Eleganza II
> >
> > _______________________________________________
> > GMCnet mailing list
> > Unsubscribe or Change List Options:
> > http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
> >
>
>
> --
> Jim Kanomata
> Applied/GMC, Newark,CA
> jimk
> http://www.appliedgmc.com
> 1-800-752-7502
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
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>

--

*John Phillips*
 
Jimk, I assumed (which is usually a mistake) that the OP meant it might be possible to use the new rear engine C8 transmission, which has axle stubs
sticking out each side to drive the front wheels of the GMC, so there would be no need for a transfer case and front differential. It's all in one
transmission and differential (locking I assume), I guess that's called a transaxle .

If installed in a GMC though, lining up the axles, it looks like the motor would be too far forward, maybe even poking out the front grill.

https://cdn.drivingline.com/media/2317249/c8-corvette-tech-15.jpg?quality=70&mode=pad&copymetadata=true&w=400

--
Todd Snyder, Buffalo NY
1976 Eleganza II
 
'IF' you could run the trans in reverse, and 'IF' you could get the programming to run it stand alone, you might get a reverse rotation cam and run
the motor in reverse and make it work with the motor behind the trans, 'IF' you could afford the whole package.
Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM
 
Unfortunately, the new C8 transmission is also a dual clutch, automated manual.. Not a traditional slush box automatic. Not sure how that would work
with the loads we have.

Also, as mentioned above, it would be a very long assembly, and the motor would likely be sticking out the front of the grill..

Interestingly, the Corvette has had a transaxle since I think the C5... It's just been mounted at the end of a torque tube. I want to say I've seen
conversions where a standard automatic like a 4L80 or 6L80 from say a camaro has been mounted to a corvette transaxle rear assembly for use in
mid-engine swaps, etc...

--
Mark S. '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX
 
> 'IF' you could run the trans in reverse, and 'IF' you could get the programming to run it stand alone, you might get a reverse rotation cam and
> run the motor in reverse and make it work with the motor behind the trans, 'IF' you could afford the whole package.
> Hal

That's interesting, Hal... Conversions to do this are common on marine engines... Marine engines would also be suitable for the type of use our
engines see in motorhome service...

Would the Torque Converter need to be changed to reverse rotation as well? Transmission pumps too, maybe?...

--
Mark S. '73 Painted Desert,
Manny 1 Ton Front End,
Howell Injection,
Leigh Harrison 4bag and Rear Brakes,
Fort Worth, TX
 
I'd guess the pump in the DCT might be problematic but I really have no real information to go on. As for the torque converter, the vanes would be
reversed so I don't think they could be made to work reversed. It's always fun to re-engineer these things. I'm in the very early stages of a
completely different approach to powering a GMC. When I get a little further along I'll share a few more details. Hal
--
1977 Royale 101348,

1977 Royale 101586, Diesel powered,

1975 Eleganza II, 101230,

1974 Eagle Bus 45',w/slideout,

Rio Rancho, NM
 
Bump the front of the grille out like one of those old corrugated Citroen bread trucks!!! Remember the Rolls Royce grilles on VW Beetles? Something real classy like that. They’ll never know it has a Chevy engine.

Still - I’d love to have a modern drivetrain alternative. I had hopes for the Diesel Ram vans, but I don’t think they are importing them, and they probably aren’t up to the task. I’m thinking Tesla…

Larry Davick
A Mystery Machine
1976 Palm Beach
Fremont

>
> I'd guess the pump in the DCT might be problematic but I really have no real information to go on. As for the torque converter, the vanes would be
> reversed so I don't think they could be made to work reversed. It's always fun to re-engineer these things. I'm in the very early stages of a
> completely different approach to powering a GMC. When I get a little further along I'll share a few more details. Hal
> --
> 1977 Royale 101348,
>
> 1977 Royale 101586, Diesel powered,
>
> 1975 Eleganza II, 101230,
>
> 1974 Eagle Bus 45',w/slideout,
>
> Rio Rancho, NM
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Interesting question for the Gurus. Can the ring gear in a GMC final drive be swapped side to side as it can in an old VW transaxle? Ask me how I
learnt this trick on a VW buss with a 4 speed reverse that screamed but only one forward speed of like 10mp hwide open. Seems as if, if it could, we
could evaluate other transmission possibilities without worrying about direction of rotation.
Couldja>?

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
Johnny,
Yes the ring gear assemble can be reversed in the VW Bus transaxle. I had 21 window with sunroof that I bought in early 1969 without an engine. I also had a 64 corvair 110 HP motor. Bought the Crown adapter plate and starter adapter and had a local VW service place swap the ring gear assembly and set it up. The bus ran extremely well and was a cruiser with the extra HP.

JR Wright
Michigan

>
> Interesting question for the Gurus. Can the ring gear in a GMC final drive be swapped side to side as it can in an old VW transaxle? Ask me how I
> learnt this trick on a VW buss with a 4 speed reverse that screamed but only one forward speed of like 10mp hwide open. Seems as if, if it could, we
> could evaluate other transmission possibilities without worrying about direction of rotation.
> Couldja>?
>
>
> --johnny
> --
> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
> Braselton, Ga.
> I forgive them all, save those who hurt the dogs. They must answer to me in hell
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
John W.:
I knew there was some reason I liked you so much - nice taste in vehicles!
Mike/The Corvair a holic

Sent from my iPhone

>
> Johnny,
> Yes the ring gear assemble can be reversed in the VW Bus transaxle. I had 21 window with sunroof that I bought in early 1969 without an engine. I also had a 64 corvair 110 HP motor. Bought the Crown adapter plate and starter adapter and had a local VW service place swap the ring gear assembly and set it up. The bus ran extremely well and was a cruiser with the extra HP.
>
> JR Wright
> Michigan

>>
>> Interesting question for the Gurus. Can the ring gear in a GMC final drive be swapped side to side as it can in an old VW transaxle? Ask me how I
>> learnt this trick on a VW buss with a 4 speed reverse that screamed but only one forward speed of like 10mp hwide open. Seems as if, if it could, we
>> could evaluate other transmission possibilities without worrying about direction of rotation.
>> Couldja>?
>>
>>
>> --johnny
>> --
>> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
>> Braselton, Ga.
>> I forgive them all, save those who hurt the dogs. They must answer to me in hell
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
Thanks!

>
> John W.:
> I knew there was some reason I liked you so much - nice taste in vehicles!
> Mike/The Corvair a holic
>
> Sent from my iPhone
>

>>
>> Johnny,
>> Yes the ring gear assemble can be reversed in the VW Bus transaxle. I had 21 window with sunroof that I bought in early 1969 without an engine. I also had a 64 corvair 110 HP motor. Bought the Crown adapter plate and starter adapter and had a local VW service place swap the ring gear assembly and set it up. The bus ran extremely well and was a cruiser with the extra HP.
>>
>> JR Wright
>> Michigan

>>>
>>> Interesting question for the Gurus. Can the ring gear in a GMC final drive be swapped side to side as it can in an old VW transaxle? Ask me how I
>>> learnt this trick on a VW buss with a 4 speed reverse that screamed but only one forward speed of like 10mp hwide open. Seems as if, if it could, we
>>> could evaluate other transmission possibilities without worrying about direction of rotation.
>>> Couldja>?
>>>
>>>
>>> --johnny
>>> --
>>> Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
>>> Braselton, Ga.
>>> I forgive them all, save those who hurt the dogs. They must answer to me in hell
>>>
>>>
>>> _______________________________________________
>>> GMCnet mailing list
>>> Unsubscribe or Change List Options:
>>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>>
>>
>> _______________________________________________
>> GMCnet mailing list
>> Unsubscribe or Change List Options:
>> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
 
I know thw VW will reverse. My question is, will the GMC reverse?

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
Three different questions here:

Why do you want to reverse the existing final drive?
** you can't want to reverse the TH425, because a lot of it won't like that idea very much.

Can the ring in the final drive be reversed?
** I can bet that Craig or Walt can tell you if the ring in the final drive can be flipped.

Why do people love lots of speeds in transmissions?
** The lots of gears in little and sports cars is to stay close to the power peak when you need all you can get.

The rage of lots of speeds transmissions in common vehicles now is an emissions move. The emissions are minimum at the peak of volumetric efficiency.
Engineers often refer to this as a island, and it is if you ever get to see a full engine curve set. (There is a lot more to a map than advance and
F/A.)
And someone on FB wanted overdrive! We already have overdrive in the 307FD. That is why JimK sells 3.55 & 3.70.

Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
I don't wanna reve4rse the 425, it works fine like it is. I want to reverse the input to the final drive to offer other options.

--johnny
--
Foolish Carriage, 76 26' Eleganza(?) with beaucoup mods and add - ons.
Braselton, Ga.
I forgive them all, save those who hurt the dogs. They must answer to me in hell
 
> I don't wanna reve4rse the 425, it works fine like it is. I want to reverse the input to the final drive to offer other options.
>
> --johnny

OK, Keep thinking.
That is a very effiecent and inexpensive process that so many seem to lack the capability to do these days.....
Matt
--
Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
Electronically Controlled Quiet Engine Cooling Fan
OE Rear Drum Brakes with Applied Control Arms
SE Michigan - Twixt A2 and Detroit
 
These discussions are very good as it helps the coomunity.

On Sat, Aug 3, 2019 at 7:02 AM Matt Colie via Gmclist <

> > I don't wanna reve4rse the 425, it works fine like it is. I want to
> reverse the input to the final drive to offer other options.
> >
> > --johnny
>
> OK, Keep thinking.
> That is a very effiecent and inexpensive process that so many seem to lack
> the capability to do these days.....
> Matt
> --
> Matt & Mary Colie - '73 Glacier 23 - Members GMCMI, GMCGL, GMCES
> Electronically Controlled Quiet Engine Cooling Fan
> OE Rear Drum Brakes with Applied Control Arms
> SE Michigan - Twixt A2 and Detroit
>
> _______________________________________________
> GMCnet mailing list
> Unsubscribe or Change List Options:
> http://list.gmcnet.org/mailman/listinfo/gmclist_list.gmcnet.org
>
--
Jim Kanomata
Applied/GMC, Newark,CA
jimk
http://www.appliedgmc.com
1-800-752-7502
 
In my imagination if you could reverse the C8 powertrain it would be intruding into the step area and even the hallway.
--
John Lebetski
Woodstock, IL
77 Eleganza II
 
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