8 speed auto in a gen 5 viper

[JETSTAR]

I am toying with the idea of installing a 8 speed auto transmission with paddle shifters.
The cost of doing this would run around $12K to $15K with all new parts.
Just wondering if anyone would be interested in having this done before I spend the money on R&D to do this to one of my cars.
Thanks
Wayne

 

[ViperJeff]

Do it!!!!!!


Got an 8 speed auto in my truck. It Rocks!

 

[Mark1107]

Instead of doing R&D what about the hellcat 8 speed auto? It can handle the torque.

 

[Free2go]

This ought to be interesting.....

 

[JETSTAR]

Instead of doing R&D what about the hellcat 8 speed auto? It can handle the torque.

way too BIG it won't fit in the hole and no stand alone controller

 

[anton28]

This would be a badass mod!

 

[JETSTAR]

Ordered the transmission today

 

[ViperJeff]

Outstanding

 

[anton28]

Looking forward to this outcome!

 

[Camfab]

Just curious what auto your thinking of using? If the HD Hellcat version is too big, will the one your sourcing handle the Vipers torque on a long term basis? Sounds like a fun build.

 

[Texas1]

Subscribed!!!

 

[JETSTAR]

Just curious what auto your thinking of using? If the HD Hellcat version is too big, will the one your sourcing handle the Vipers torque on a long term basis? Sounds like a fun build.

8L90 same trans in the 2015 ZO6

 

[Bobpantax]

Looks like you will have to change the differential ratio to go with the 8L90 gearing if what GM did on the Z06 and the V series Cadies is any indication. Or, do you also intend to change out the diff?

 

[ViperJeff]

This will be fun to watch

 

[johnk]

It would be very interesting to see some quarter mile times with the stock transmission vs the new auto trans. good luck....

 

[JETSTAR]

Looks like you will have to change the differential ratio to go with the 8L90 gearing if what GM did on the Z06 and the V series Cadies is any indication. Or, do you also intend to change out the diff?

Interesting point I might look at putting the old 3.07 back in since were not trying to get 30 mpg but the 1/4 time would be off the chain with the stock ratio

 

[Bobpantax]

I do not think it will work with the stock ratio. Look at what is used in the Z06. If you keep the stock ratio, on a good hook up, my guess is that you will snap a half shaft pretty quickly and, if not a half shaft, you will get a diff failure and/or a driveshaft failure. You have to sync the tranny ratios with the diff ratio - but you already know that. It definitely should be interesting. You might want to speak with Mark J at Woodhouse about your project since he has done a few automatic cars but not with the Vette tranny.

 

[Viper X]

Sounds like a very interesting build.

A few thoughts:

Have never seen a drive shaft failure yet in a Gen 3 or newer Viper...and I've run a Quaife with drag radials at 18 psi, Unitrax's upgraded 1/2 shafts, John Donato built T-56, stock flywheel and upgraded clutch in a 925 rwhp, 860 rwhp Gen 3 Viper. Paxton car with the factory computer tuned to run 91 octane (CA).

I did blow 5 diffs trying to get the right one into the car. The Quaife has been bullet proof so far, 40K miles.

I also lost all the teeth on the second gear input and output shafts once while running quickly over a bumpy section of road.

A few clutches have bit the dust.

Would love to have that 8 speed auto in my ACR for the track.....

 

[emericr]

Interesting build for sure. Wish the factory would offer that option...

 

[JETSTAR]

Sounds like a very interesting build.

A few thoughts:

Have never seen a drive shaft failure yet in a Gen 3 or newer Viper...and I've run a Quaife with drag radials at 18 psi, Unitrax's upgraded 1/2 shafts, John Donato built T-56, stock flywheel and upgraded clutch in a 925 rwhp, 860 rwhp Gen 3 Viper. Paxton car with the factory computer tuned to run 91 octane (CA).

I did blow 5 diffs trying to get the right one into the car. The Quaife has been bullet proof so far, 40K miles.

I also lost all the teeth on the second gear input and output shafts once while running quickly over a bumpy section of road.

A few clutches have bit the dust.

Would love to have that 8 speed auto in my ACR for the track.....

Once I get done with the Gen 5 the Gen 3-4 cars should be no problem but you will have to go back to the drawing board on the gear ratio I am going with the 3.07 to start with but will offer options depending on the customer.
I plan to install the trans in my Gen 5 race car and do some heavy R&D track days just to see how strong it is. All the reports I've seen so far have been very positive The ZO6 engine may overheat but very few trans problems
Thanks
Wayne

 

[Viper X]

Wayne,

Do you know the rear gear ratio in the new Z06?

My 09 ACR is also running 3.07.

Would be an interesting swap. Anxious to hear your results.

Dan

 

[Dave1968]

3:73 with stronger 1/2 shafts?

 

[JETSTAR]

Wayne,

Do you know the rear gear ratio in the new Z06?

My 09 ACR is also running 3.07.

Would be an interesting swap. Anxious to hear your results.

Dan

2.41
Model Years Make and Model Final Drive Ratio
2015–present Cadillac Escalade [2] 3.23
2015–present Chevrolet Corvette (C7) Stingray [3] 2.41 (std)
2.73 (Z51)
2015-current Chevrolet Corvette (C7) Z06 [4] 2.41
2015–present Chevrolet Silverado/GMC Sierra[5] 3.23 (std.)
3.42 (Max Trailering Package)
2015–present GMC Yukon Denali/Denali XL 3.23
2016–present Cadillac ATS-V 2.85
2016–present Cadillac CTS-V 2.85

 

[JETSTAR]

just a quick update
The trans has been a challenge to get but should be here next week according to my GM dealer
Thanks
Wayne

 

[ViperJeff]

Thanks for the update

 

[pitdad]

How's the build going?

 

[JETSTAR]

How's the build going?

Kind of hit a decision point
It looks like my best option is to install the entire transmission and rearend from the Vette in the rear of the Viper.
So I'm looking for the parts
Thanks
Wayne

 

[pitdad]

Sounds cool - can't wait to see progress..

 

[Viper LP]

I am toying with the idea of installing a 8 speed auto transmission with paddle shifters.
The cost of doing this would run around $12K to $15K with all new parts.
Just wondering if anyone would be interested in having this done before I spend the money on R&D to do this to one of my cars.
Thanks
Wayne

I would be interested will text you today about it...Lou

 

[ringram]

Probably better off with the camaro 8 speed? Vette will have torque tube config etc..