Gen IV Transmission Upgrade

Bobpantax

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I promised to report back after I had it done and tested it a bit.

The work was done by John Donato. John is a retired Chrysler ****** engineer. His shop is located in back of his house. The only negative I would mention is that John can disappear for periods of time because he does some work for the DOE. When he is away, he is sometimes out of touch because of where he is located.

All of the following was done:

1. The gen IV transmission was taken apart. All parts to be resused were shot ball peened ( I believe that John sends them out to a third party for this process.) This allegedly strengthens them.

2. An upgraded carbon Kevlar second gear synchro pack was installed.

3. The fifth and sixth gears were changed to .8 and .63 from .74 and .5.

4. Tolerances were tightened up a bit.

Results:

1. The car now has a true six speed transmission. The difference in fifth and sixth is noticeable in a very good way. ( When I shift from fourth to fifth at speed the RPM drop is now 500 RPM less.)

2. NGR at idle is basically gone.

3. GR in any gear is just about eliminated.

4. Keep in mind that I have the stiffer motor and ****** mounts so I was not expecting this much of a change in NGR and GR.

5. It seems to go into reverse a bit easier than it used to.

6. I have tested it up to 140 MPH on a deserted highway in Mexico. It was perfect.

7. I will not discuss price. Please consult John for that.

8. This change is not for garage queens. It is something for people to consider who use fifth, and possibly sixth gear, depending on your diff ratio, in standing mile events, higher speed road courses, and in Mexico. The 2010 Gen IV has the .8 fifth gear but still has the .5 sixth gear - probably for gas mileage purposes.

9. Please do not ask me how this affected my gas mileage because I really do not consider that a relevant question for performance modifications and I do not keep tabs on that type of data.

10. Overall, I am very pleased with the mod. The only bad thing was doing without my car while the ****** was shipped up to John, upgraded by John, and then sent back for reinstallation. By the way, a special container is needed to safely ship the ******. If you do not have one, John can ship one down to you to use ( at your cost). After you get the ****** back, you ship the empty container back to John.

[SIZE=+2]Donato Engineering[/SIZE]
Manufacturer - Transmission Parts 2934 East Maple Tel: 248-676-8554 Milford MI Fax: 248-676-8286 48381 Contact: John [email protected]


I hope the above is useful.
 
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EZ 2B Green

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+1 on this mod. John did the same for me less the shot peening. I concur with the above except for number 8. Anyone who drives their car and spends a significant amount of time on the highway will benefit from this upgrade.
 

TrackAire

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Nice.....time for another Standing Mile run to try her out!!

Did John discuss any type of trans cooler for your setup?

Enjoy the ride, a true 6 speed is on my "to do" list.

Cheers,
George
 

Dan Cragin

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John is a great guy. He was one of the original "Team Viper" guys and was resposible for punishment testing the Viper driveline. In 1993 he knew exactly how many burnouts you could do before the differential fails!

He has done my transmissions for years and it is worth the wait.
 

Bobpantax

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Yes. After considering what I use the car for and the time allocated to each type of activity I decided that I did not need it.

Nice.....time for another Standing Mile run to try her out!!

Did John discuss any type of trans cooler for your setup?

Enjoy the ride, a true 6 speed is on my "to do" list.

Cheers,
George
 

Trans Doc

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Bob, Thanks for the assessment of the upgrades and what were you doing in Mexico with your Viper ?
The work with the DoE has finished and also the full build of four Challenger Drag Paks with one to complete. This will help with the turn around time on the transmissions.
 
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