t56 people please step inside
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,892
Likes: 3
From: Springfield Illinois
t56 people please step inside
I am about ready to mod my cross member for my Viper T56.. I wanted to know a couple things.. I've read on here that I should not worry about the drive shaft angle that I should put the trans as high up into the tunnel as possible.. Thoughts???
What do you have to drive your speedometer? If you have the abbot cable x box, how many # of teeth are on the transmission exciter gear?
For those that have automatic cars and that have switched over.. how did you wire or how did you get your back up lights to work?
Also, what tranny fluid are you running? Dex/Merc?
What do you have to drive your speedometer? If you have the abbot cable x box, how many # of teeth are on the transmission exciter gear?
For those that have automatic cars and that have switched over.. how did you wire or how did you get your back up lights to work?
Also, what tranny fluid are you running? Dex/Merc?
Melting Slicks
Joined: Feb 2001
Posts: 3,330
Likes: 13
From: Europe , Luxembourg
Hi
That's what I did, mount it as high against the tunnel as possible .
I used a auto cross member, slightly modified at the tranny attachment area and mounted a couple of inches further back . Reason that I used the original cross member is our biyearly technical inspection. I didn't wanted to point them directly to this mod. Looks all more or less original. The aftermarked crossmembers are bend tube style and very obvious to spot.
My Viper T56 had the mechanical speedo output. I used the M21 speedo gear ( I think red ) , but had to change it because I went from 3.70 to 4.11 rear end later on in order to be able to use the 6th gear better.
Here you may see how much further back I mounted the crossmember. You can see the leftovers of the manual member being cut out and the offset of the auto tranny mount holes now further back. Not a lot, but required.
Rgds. Günther
That's what I did, mount it as high against the tunnel as possible .
I used a auto cross member, slightly modified at the tranny attachment area and mounted a couple of inches further back . Reason that I used the original cross member is our biyearly technical inspection. I didn't wanted to point them directly to this mod. Looks all more or less original. The aftermarked crossmembers are bend tube style and very obvious to spot.
My Viper T56 had the mechanical speedo output. I used the M21 speedo gear ( I think red ) , but had to change it because I went from 3.70 to 4.11 rear end later on in order to be able to use the 6th gear better.
Here you may see how much further back I mounted the crossmember. You can see the leftovers of the manual member being cut out and the offset of the auto tranny mount holes now further back. Not a lot, but required.
Rgds. Günther
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I also had to modifymy cross member. I already had made my welded in member removeable. I then had to cut away quite a bit and weld in a bracket then drill the mounting holes.
I switched over to electronic gauges on mine so I used the original sensor on the trans for the speedo output. Mine T56 is from a 06 GTO.
I wired the reverse lights from the switch on the trans to the two wires that were originaaly for the back up lights. This will work regardless of an auto car or a manual car.
I switched over to electronic gauges on mine so I used the original sensor on the trans for the speedo output. Mine T56 is from a 06 GTO.
I wired the reverse lights from the switch on the trans to the two wires that were originaaly for the back up lights. This will work regardless of an auto car or a manual car.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,892
Likes: 3
From: Springfield Illinois
Wow.. I didn't realize anyone had responded.. Sorry about that guys.
I have the transmission sitting in the car attached to the engine. I noticed today that my tail shaft housing or where the yolk would come out is very close to my tunnel where the e brake console would be.. Could it be that my engine and transmission are not sitting straight? I am afraid if i don't cut the tunnel it will destroy it as soon as the car moves an inch.. You guys didn't have to mod your tunnel did you? I will post a pic asap!
I have the transmission sitting in the car attached to the engine. I noticed today that my tail shaft housing or where the yolk would come out is very close to my tunnel where the e brake console would be.. Could it be that my engine and transmission are not sitting straight? I am afraid if i don't cut the tunnel it will destroy it as soon as the car moves an inch.. You guys didn't have to mod your tunnel did you? I will post a pic asap!
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I did not have to modify the tunnel but it is extremly close. I am using a 1330 ujoint. The 1310 is smaller and will fit no problem. I did have to remove 1 stud for the battery cable and slightly reroute the cable. I had to cut a bigger hole for my shifter also. My problem was the reverse lockout. On the GTO T56 it is way back on the trans so I had to heavily modify the switch.
In comparing the 2 pictures your T56 looks longer than mine for some reason.
In comparing the 2 pictures your T56 looks longer than mine for some reason.
Last edited by Gordonm; Jun 11, 2010 at 07:13 AM.
Pro
Joined: Nov 2002
Posts: 599
Likes: 16
From: vista CA
I tried to get the driveshaft angles equal, and small. Ended up mounted high in the tunnel. Had to pound out a portion of the tunnel to clear ujoint rotating. I also modified the starter cable routing and the ebrake pulley mount to clear. Mine was auto originally, modified stock crossmember similar to above (but not as nice). Used electric speedo, and no problem getting the switch on the t56 to drive a backup light. Had the stock driveshaft shortened and balanced.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,892
Likes: 3
From: Springfield Illinois
I did not have to modify the tunnel but it is extremly close. I am using a 1330 ujoint. The 1310 is smaller and will fit no problem. I did have to remove 1 stud for the battery cable and slightly reroute the cable. I had to cut a bigger hole for my shifter also. My problem was the reverse lockout. On the GTO T56 it is way back on the trans so I had to heavily modify the switch.
In comparing the 2 pictures your T56 looks longer than mine for some reason.
In comparing the 2 pictures your T56 looks longer than mine for some reason.
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Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,892
Likes: 3
From: Springfield Illinois
I tried to get the driveshaft angles equal, and small. Ended up mounted high in the tunnel. Had to pound out a portion of the tunnel to clear ujoint rotating. I also modified the starter cable routing and the ebrake pulley mount to clear. Mine was auto originally, modified stock crossmember similar to above (but not as nice). Used electric speedo, and no problem getting the switch on the t56 to drive a backup light. Had the stock driveshaft shortened and balanced.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
Pro
Joined: Nov 2002
Posts: 599
Likes: 16
From: vista CA
Yeah, I switched all my gages to VDO: elec speedo and tach, volts, water temp, oil press, gas level - and rather than a clock, a vacuumn gage to let me know when somethings is wrong, and get better mileage when in that mood.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
I had the body off the car when I installed the drivetrain. The T56 is so much longer than the 4-speed that there is a significant drivetrain angle when looking down from the top of the frame. Much harder to see when looking at from below. The U-joints aren't going to know what direction the angle is coming from as long as there is an angle. I had to lower the trans after putting the body on to get tunnel clearance, but since the side angle didn't change I crossed my fingers and hoped for the best. I have had the car up to 80 mph with no dirvetrain vibrations at all. IIRC most people see vibrations at 65-70 mph if there is a driveline problem.
I had to cut a hole in the pass. side of the fiberglass tunnel for yoke clearance when the trans was sitting high, but after lowering it the hole wasn't needed.
Rick B.
I had to cut a hole in the pass. side of the fiberglass tunnel for yoke clearance when the trans was sitting high, but after lowering it the hole wasn't needed.
Rick B.
Thread Starter
Drifting
Joined: Apr 2007
Posts: 1,892
Likes: 3
From: Springfield Illinois
Well I decided to hold off modding the cross member until i had the driveshaft shortened and installed. Drive shaft is installed and I am afraid my 1350 u joint at the yolk is too close to the battery cable...
Gordonm - you said you had to re route the cable.. could you tell me where you re routed it to?
That interior looks sharp! I bet your car is a blast to drive!!
I can slightly see the angle you're talking about.. I'm crossing my fingers!! Did you have to reroute the battery cable?
Gordonm - you said you had to re route the cable.. could you tell me where you re routed it to?
Didn't know earlier C3's had fiberglass tunnels.
Yeah, I switched all my gages to VDO: elec speedo and tach, volts, water temp, oil press, gas level - and rather than a clock, a vacuumn gage to let me know when somethings is wrong, and get better mileage when in that mood.
Yeah, I switched all my gages to VDO: elec speedo and tach, volts, water temp, oil press, gas level - and rather than a clock, a vacuumn gage to let me know when somethings is wrong, and get better mileage when in that mood.
I had the body off the car when I installed the drivetrain. The T56 is so much longer than the 4-speed that there is a significant drivetrain angle when looking down from the top of the frame. Much harder to see when looking at from below. The U-joints aren't going to know what direction the angle is coming from as long as there is an angle. I had to lower the trans after putting the body on to get tunnel clearance, but since the side angle didn't change I crossed my fingers and hoped for the best. I have had the car up to 80 mph with no dirvetrain vibrations at all. IIRC most people see vibrations at 65-70 mph if there is a driveline problem.
I had to cut a hole in the pass. side of the fiberglass tunnel for yoke clearance when the trans was sitting high, but after lowering it the hole wasn't needed.
Rick B.
I had to cut a hole in the pass. side of the fiberglass tunnel for yoke clearance when the trans was sitting high, but after lowering it the hole wasn't needed.
Rick B.
Race Director
Joined: Dec 1999
Posts: 19,610
Likes: 778
From: Forked River NJ
I did not move it much but one of the mounting bolts for the cable was in the way. The shifter hole is more centered so I just had to kind of push the cable to the side a bit. Not really rerouted just moved over some.
Safety Car
Joined: Aug 2001
Posts: 4,883
Likes: 11
From: North Easton Mass
Rick B.
Pro
Joined: Nov 2002
Posts: 599
Likes: 16
From: vista CA
FRSTR90 - thanks for the kind words! I DO enjoy driving it, and having the T56 is sooo much fun
