T56 conversion question for 1972 C3
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T56 conversion question for 1972 C3
I want to put a T56 Magnum into my 72, which was originally a Turbo 400 Auto. I know you have to cut the tunnel where the shifter is, but I came across this article that says "some models require an additional clearance cut to clear the top of the transmission." I can't tell from the picture, where they made this cut. Can anyone identify from the pic or from experience where that is? (picture is in the linked article below)
http://www.superchevy.com/how-to/040...speed-install/
I already put my pedal assembly in & reassembled the driver side dash, so I'm a little concerned about being able to reach whatever location they are referencing. Also wandering if it will cause any fit problems with the radio, or anything else under the center console. I plan to use an original style mechanical clutch, and bell housing for the original gen1 engine.
http://www.superchevy.com/how-to/040...speed-install/
I already put my pedal assembly in & reassembled the driver side dash, so I'm a little concerned about being able to reach whatever location they are referencing. Also wandering if it will cause any fit problems with the radio, or anything else under the center console. I plan to use an original style mechanical clutch, and bell housing for the original gen1 engine.
Instructor
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Why not go for a Borg T5 WC from a Camaro Shorten the drive shaft, no body modifications just some work on the mount and gear shifter. Now you have a 5 speed with a .63 final drive without touching the body on your car. Just a proposal for you if you have not already considered that option.
Is my vette stock?? HAHA
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I was looking for some T5 / muncie comparison measurements and found this....
http://www.vettemod.com/forum/showthread.php?t=399
Hes got a 82 but it should give you an idea
http://www.vettemod.com/forum/showthread.php?t=399
Hes got a 82 but it should give you an idea
Last edited by Rescue Rogers; Jan 28, 2020 at 06:23 AM.
Burning Brakes
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I put a t56 in my 69, you should only need to cut wide around the shifter, WATCH the battery cable. Search my post I've help a lot of folks on this, and covered almost every thing.
Later cars required an additional cut towards the front, ours do not. At least not one that I have seen.
Later cars required an additional cut towards the front, ours do not. At least not one that I have seen.
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From: FL
T-56 Magnum in a '75. The tunnel cut for the shifter is required. I also had to massage the tunnel for U-joint clearance. Basically a 2"x2" section of the tunnel cut out and reglassed about 1/2" wider. Right by the passenger seat so completely invisible. Metal florr cars can just clearance with a hammer.
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Thanks, That was the first trans I was considering, because they are less expensive, then was leaning toward a TKO 600 for the extra torque, but finally decided to go all the way with a Magnum, because I like the closer gear spacing with the 2 overdrives.
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Thanks NY City, By "ours do not" I assume you mean a 1972 is good to go without the extra cut. As far as the 2X2X .5 inch relief for the driveshaft clearance that the gentleman with the 1975 mentioned, does that get in the way of the original seats? I think my seats have about 0 clearance between the the tunnel and the side of the seat (at least at the top of the seat).
Burning Brakes
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From: New York
I meant early year cars with glass floors. I modified my tunnel and I'm running a 1350, you would clear with a 1330. You will have clearance by the seat...I'm running custom seats, stock seats will clear.
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From: FL
Thanks NY City, By "ours do not" I assume you mean a 1972 is good to go without the extra cut. As far as the 2X2X .5 inch relief for the driveshaft clearance that the gentleman with the 1975 mentioned, does that get in the way of the original seats? I think my seats have about 0 clearance between the the tunnel and the side of the seat (at least at the top of the seat).
BTW, I believe that nyciti has a Camaro T-56. The T-56 Magnum is a different transmission and much bigger in the tailshaft area. Transmission mount is ~2" further back than on the T-56 and required that I modify the Bow Tie Overdrive crossmember that was designed for the F-Body T-56 swap into C-3s.
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From: FL
FYI, if you do not have a bellhousing yet, the part you want is a Quicktime RM-6023PB. This will mount a GM T-56 Magnum to a legacy small or big block Chevrolet and has the provisions for the clutch ball.
https://www.holley.com/products/driv...arts/RM-6023PB
You will also need a throwout bearing sleeve for the T-56 Magnum. Various vendors have that.
Tip: Get ARP 12 point bolts and a wobble socket for the bellhousing bolts. Makes life much easier. There is also one bolt that needs a socket head bolt due to clearance.
https://www.summitracing.com/parts/arp-642-1250
https://www.holley.com/products/driv...arts/RM-6023PB
You will also need a throwout bearing sleeve for the T-56 Magnum. Various vendors have that.
Tip: Get ARP 12 point bolts and a wobble socket for the bellhousing bolts. Makes life much easier. There is also one bolt that needs a socket head bolt due to clearance.
https://www.summitracing.com/parts/arp-642-1250
Last edited by SteveG75; Jan 29, 2020 at 09:31 AM.
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Aside from acting as a steel scatter shield, are there any disadvantages (or maybe fit advantages?) to getting a stock aluminum bell housing, and going with one of the adapter plates that I've seen (I think maybe American Powertrain has one?). Also, would the 1330 yoke that nyciti mentioned fit into a magnum, and eliminate the need for the driveshaft clearance modify, and finally would it be simpler to use a Camaro T56 vs a magnum, if it is smaller?
Thanks for both your inputs. As you can see, I'm just beginning research on this, and am starting to feel intimidated back to my original TKO600 choice. Any opinions on the TKO 600? (aside form the 2-3 shift I often read about)
Thanks for both your inputs. As you can see, I'm just beginning research on this, and am starting to feel intimidated back to my original TKO600 choice. Any opinions on the TKO 600? (aside form the 2-3 shift I often read about)
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From: FL
Aside from acting as a steel scatter shield, are there any disadvantages (or maybe fit advantages?) to getting a stock aluminum bell housing, and going with one of the adapter plates that I've seen (I think maybe American Powertrain has one?). Also, would the 1330 yoke that nyciti mentioned fit into a magnum, and eliminate the need for the driveshaft clearance modify, and finally would it be simpler to use a Camaro T56 vs a magnum, if it is smaller?
Thanks for both your inputs. As you can see, I'm just beginning research on this, and am starting to feel intimidated back to my original TKO600 choice. Any opinions on the TKO 600? (aside form the 2-3 shift I often read about)
Thanks for both your inputs. As you can see, I'm just beginning research on this, and am starting to feel intimidated back to my original TKO600 choice. Any opinions on the TKO 600? (aside form the 2-3 shift I often read about)
My yoke at the transmission is a 1310. I have a 1330 at the pinion (Tom’s Diffs 12 bolt). Halfshafts are 1350.
The Camaro T-56 is smaller which should make it easier but everyone you find is used unless you pay to get it refurbished. I was more comfortable paying for a brand new T-56 Magnum, especially with the big block.
The TKO is a good transmission as well. And an easier fit. I ran a Tremec 3550 for 10 years before all the TKO swap kits came out. Had a .62 OD fifth and I never like the drop from 4th to 5th.
The T-56 Magnum close ratio has a .8 5th and .63 6th. 2.66 first. Works perfect for me. Did my swap to the T-56 in 2011. Back then the wide ratio Magnum had a .5 6th. Now the wide ratio has the deeper first (2.97) and the .63 6th.
BTW, I have a 3.70 12 bolt with the T-56 Magnum close ratio. 25 lb flywheel. Can be a little tricky coming off the line but revs like crazy and easily smokes the tires.
Last edited by SteveG75; Jan 29, 2020 at 08:48 PM.
Burning Brakes
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I wouldn't go 1310 thats to small and not even stock for a BB back in the day, I believe they got a 1330. (I could be wrong). 1330 clears, thats whats on a turbo 400 and is stronger than a 1310. NO Offense but if I am going Magnum why step down to a 1310. If you have nothing go 1350 if you dont mind a little tunnel work. I went with a GTR rear end, he's a top notch guy to deal with! I also stepped up to a 2.5 custom built DOM drive shaft.
Last edited by nyciti; Jan 29, 2020 at 10:27 PM.
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I wouldn't go 1310 thats to small and not even stock for a BB back in the day, I believe they got a 1330. (I could be wrong). 1330 clears, thats whats on a turbo 400 and is stronger than a 1310. NO Offense but if I am going Magnum why step down to a 1310. If you have nothing go 1350 if you dont mind a little tunnel work. I went with a GTR rear end, he's a top notch guy to deal with! I also stepped up to a 2.5 custom built DOM drive shaft.
Yeah, Gary Ramadie is the man. He did my steering box, T-arms, and built the Tom's 12 bolt diff for me.
For the OP, I would seriously look into a hydraulic clutch conversion. It will make your life much easier. I had my clutch and flywheel out this summer and regret not doing the conversion then.
Burning Brakes
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From: New York
If you had to clear the tunnel it's probably a 1350 like me. I had to do the same, I didn't use a kit just pieced it together. The annoying part was the hydraulic clutch. I didnt want to use a Truck one, so I had to figure out angle to build the adapter for a tilton. Which btw is 15degrees and 1.5" - 2" long.
Race Director
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Silver Sport Transmission modify's the transmission case and they advertise that with their transmissions, tunnel modifications are not necessary and they have an adapter so you do not need to cut for the shifter.
Give them a call.
My big block came with 1310's at the trans and 1330's at the differential.
Give them a call.
My big block came with 1310's at the trans and 1330's at the differential.
Last edited by OldCarBum; Jan 30, 2020 at 07:35 PM.
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I know its a tough question to ask anyone that has gone through a lot of work to do a conversion, but are there any regrets to installing the six speed? (Mechanically speaking) Does the tight fit cause any issues like noise or bumping into the body on hard acceleration or letting off the gas etc. Otherwise,... I think I'm sold on a magnum
Burning Brakes
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From: New York
If you don't get the DD cut and balance correctly you could have vibration issues. Other than that NO! I've done a manual conversion in at least 6 cars it's a must for me. Other than battery cable being in an annoying spot it's pretty straightforward.