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Manual Transmission Conversion

Posted: Wed Mar 01, 2017 10:15 pm
by kras007
Just finished a manual transmission conversion on a 2012 9C1. Photos to follow
Here are some details on the build

Parts:
2009 GXP- Transmission mount, crossmember, shifter assembly, engine/transmission harness, clutch position sensor jumper harness, clutch slave cylinder
2012 Camaro- clutch pedal assembly and transmission
LS7- Clutch, flywheel, and pressure plate
WAM Custom BCM Program
Custom ECM tune

Procedure:
Separate and lift body from powertrain. Send out ECM and BCM for custom tuning. Remove factory engine/trans harness. Remove automatic trans and remove engine from front cradle. Remove cylinder heads and perform DOD delete on engine and install camshaft, valve springs, and headers.
Bolt on LS7 Clutch and Tremec 6spd transmission from 2012 Camaro.
While body is lifted off of powertrain brake booster was removed and drilled hole in firewall for clutch slave cylinder. This required removing parking brake foot pedal assembly and bracket that was welded to I/P and firewall. Camaro clutch pedal assembly could then be bolted in place.
Lower body back onto powertrain. Transmission shifter lined up and bolted in place where factory automatic shifter was installed. Modified automatic transmission cooler lines to adapt to manual transmission so factory transmission cooler could still be used.
Spent hours reviewing GXP and Caprice wiring schematics to determine modifications that were necessary to factory Caprice body side harness. Most modifications were adding in circuits that were missing from factory harness. These were done using factory terminals and installed into factor connectors. Also the Caprice PPV has a heavy duty engine cooling fan system completely different from a GXP and requires circuits removed from undressed fuse panel and adapted to PPV cooling fan system. After all wiring modifications were made I was able to perform clutch pedal position learn, brake pedal position learn, etc. Vehicle started up and I was able to resolve all warning lights. Currently it has no warning lights illuminated. Vehicle has been test driven and it is awesome! All work was done meticulously and when looking over the vehicle it would appear it rolled off the assembly line with a manual transmission. Only thing left to do is dyno tune the the ECM program and install a G8 console to finish it off so it has a hand applied parking brake.
It has been a great project and I can't wait to build another one. Who wants one!

Re: Manual Transmission Conversion

Posted: Thu Mar 02, 2017 8:04 am
by jackleg
That's awesome! I want one.

Re: Manual Transmission Conversion

Posted: Thu Mar 02, 2017 12:54 pm
by kras007
Pics

Re: Manual Transmission Conversion

Posted: Thu Mar 02, 2017 12:57 pm
by kras007
Pic

Re: Manual Transmission Conversion

Posted: Thu Mar 02, 2017 1:03 pm
by kras007
Pic

Re: Manual Transmission Conversion

Posted: Thu Mar 02, 2017 1:05 pm
by kras007
Pic

Re: Manual Transmission Conversion

Posted: Thu Mar 02, 2017 1:19 pm
by elc32955
Here's some more pics, posted on behalf of the OP.
mt1.jpg
mt1.jpg (28.74 KiB) Viewed 39955 times
mt2.jpg
mt2.jpg (30.99 KiB) Viewed 39955 times
mt3.jpg
mt3.jpg (31.47 KiB) Viewed 39955 times
mt4.jpg
mt4.jpg (21.77 KiB) Viewed 39955 times
mt5.jpg
mt5.jpg (29.64 KiB) Viewed 39955 times
Eric

Re: Manual Transmission Conversion

Posted: Sat Mar 04, 2017 2:13 pm
by Gerome
This is too cool ! I can see a lot of 9c1's becoming manuals . Great info also . Did you get the harness used or from the dealer ?

Re: Manual Transmission Conversion

Posted: Sun Mar 05, 2017 6:48 am
by kras007
Engine/Transmission harness was purchased New through GM. The G8 harness connects to same body side connector that the original engine/auto trans harness used.

Re: Manual Transmission Conversion

Posted: Sun Mar 05, 2017 10:03 am
by Navy Lifer
What about the rear axle ratio--any plan to change it?

6-speed manual in GXP & SS sedan uses 3.70 ratio, and the stock PPV 2.92 is leaving lots of performance potential on the table...or, maybe you've already changed the rear axle?

Very cool thing to do--can't imagine the cost!