autogear m21y, some help...
Thread Starter
Burning Brakes
Joined: Sep 2008
Posts: 753
Likes: 0
Bought the M21Y stuff a while ago...
it seems that next week it's time to install the new gearset and new clutch , pressure plate and throwout bearing.
my mech is well experienced in overhauling european transmissions, but should he pay special attention with the M21? i mean : is there something peculiar to muncies that i must know before to start?
it seems that next week it's time to install the new gearset and new clutch , pressure plate and throwout bearing.
my mech is well experienced in overhauling european transmissions, but should he pay special attention with the M21? i mean : is there something peculiar to muncies that i must know before to start?
Le Mans Master
Joined: Apr 2007
Posts: 7,353
Likes: 72
From: Graceland in a Not Correctly Restored Stingray
5speeds (Paul C) sells a comprehensive Muncie build DVD.
Are you certain with your power that you want to go this route??? I'd really suggest talking to Paul about the M21Y before committing to installation.
As for performance alone, after the extensive acceleration modelling I've done with C3's having very similar power curves and available traction I'd change the diff ratio to a 3.55:1 and think about either M-22Z extra-wide ratio gearset or a 5-speed w/OD than to go with the M21Y setup. FWIW, with a 3.55 FDR in top gear, approaching terminal velocity will likely be a rather dodgy proposition without some aero tweaks anyway, and with an OD altogether impractical without a good bit of aero work. Of course, you may have other priorities to consider. Just some food for thought before you take the plunge.
Are you certain with your power that you want to go this route??? I'd really suggest talking to Paul about the M21Y before committing to installation.
As for performance alone, after the extensive acceleration modelling I've done with C3's having very similar power curves and available traction I'd change the diff ratio to a 3.55:1 and think about either M-22Z extra-wide ratio gearset or a 5-speed w/OD than to go with the M21Y setup. FWIW, with a 3.55 FDR in top gear, approaching terminal velocity will likely be a rather dodgy proposition without some aero tweaks anyway, and with an OD altogether impractical without a good bit of aero work. Of course, you may have other priorities to consider. Just some food for thought before you take the plunge.
Last edited by TheSkunkWorks; Apr 15, 2011 at 06:09 PM.
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
D&D Viper-Chevy T56
650 lb-ft Torque Capacity
1.125 x 26T GM Input Spline
30T Viper Output Spline
Close Ratio w/ Deep Overdrives(2.66/1.78/1.30/1.00/.80/.62)
Carbon Fibre Blocker Rings
Steel 3-4 Shift Fork
Precision built and blueprinted by D&D technicians
Direct bolt-up to GM Saginaw/Muncie/T10 bell housings
Direct bolt-up to 4-Speed aftermarket steel bell housings
Accepts stock GM clutches,linkage,T.O.B.,pilot bearing,trans. mount
7T GM Mechanical Speedo Drive or Electronic Speedo Drive
650 lb-ft Torque Capacity
1.125 x 26T GM Input Spline
30T Viper Output Spline
Close Ratio w/ Deep Overdrives(2.66/1.78/1.30/1.00/.80/.62)
Carbon Fibre Blocker Rings
Steel 3-4 Shift Fork
Precision built and blueprinted by D&D technicians
Direct bolt-up to GM Saginaw/Muncie/T10 bell housings
Direct bolt-up to 4-Speed aftermarket steel bell housings
Accepts stock GM clutches,linkage,T.O.B.,pilot bearing,trans. mount
7T GM Mechanical Speedo Drive or Electronic Speedo Drive
Thread Starter
Burning Brakes
Joined: Sep 2008
Posts: 753
Likes: 0
TSW , 63mako
of course there are many better solutions than M21Y and 4.11 but all more expensive than the usd500 of the M21Y gearset. it has been a matter of budget. My 4.11 is fine , why replace it?And i want my car to remain stock appearing , that's why i have never decided for an aftermarket transmission
I look forward to drive the car with the new gearset.i don't know if I'll find myself comfortable with that gear spacing. let's see... but i wanted lower rpm in the higher gear , both at cruise speed and when going fast
of course there are many better solutions than M21Y and 4.11 but all more expensive than the usd500 of the M21Y gearset. it has been a matter of budget. My 4.11 is fine , why replace it?And i want my car to remain stock appearing , that's why i have never decided for an aftermarket transmission
I look forward to drive the car with the new gearset.i don't know if I'll find myself comfortable with that gear spacing. let's see... but i wanted lower rpm in the higher gear , both at cruise speed and when going fast
Race Director
Joined: May 2005
Posts: 10,674
Likes: 122
From: Millington Illinois
St. Jude Donor '08-'09
TSW , 63mako
of course there are many better solutions than M21Y and 4.11 but all more expensive than the usd500 of the M21Y gearset. it has been a matter of budget. My 4.11 is fine , why replace it?And i want my car to remain stock appearing , that's why i have never decided for an aftermarket transmission
I look forward to drive the car with the new gearset.i don't know if I'll find myself comfortable with that gear spacing. let's see... but i wanted lower rpm in the higher gear , both at cruise speed and when going fast
of course there are many better solutions than M21Y and 4.11 but all more expensive than the usd500 of the M21Y gearset. it has been a matter of budget. My 4.11 is fine , why replace it?And i want my car to remain stock appearing , that's why i have never decided for an aftermarket transmission
I look forward to drive the car with the new gearset.i don't know if I'll find myself comfortable with that gear spacing. let's see... but i wanted lower rpm in the higher gear , both at cruise speed and when going fast
