need some Muncie/bellhousing/shifter measurements

[KAOS]

It is not easy for me to get these measurements while my transmission is installed and I live in a condo so maybe somebody with easy access to a partly assembeled car could help...

I need the following measurements:

1. Thickness of stock SBC bell housing (6.4"?)
2. From the Muncie front mounting surface to the bellhousing, how long is it to the center of the shifter location (17.4"?)
3. How much offset to the drivers side from top dead center of the tranny is the shifter located?

Thanks in advance for verifying my measurements as this is needed for part of my T56 conversion that I hope to complete and do a full write-up for others if they wish to go down the same path.

 

[Twin_Turbo]

[tr] [td]Trans Model [/td] [td]A [/td] [td]B [/td] [td]C [/td] [td]D [/td] [td]E [/td] [td] F [/td] [/tr] [tr] [td]GM Super T10 Muncie [/td] [td]6.3 [/td] [td] 14.2 [/td] [td] 23 [/td] [td]n/a [/td] [td]n/a [/td] [td]3.75 [/td] [/tr] [tr] [td]GM T5 V8 [/td] [td]6.3 [/td] [td]16 [/td] [td]25 [/td] [td]19 [/td] [td]21.2 [/td] [td]3.75 [/td] [/tr] [tr] [td]GM T56 F-car Prod[/td] [td] 4.9 [/td] [td]21 [/td] [td]26.4 [/td] [td]21.1 [/td] [td]23.9 [/td] [td]3.75 [/td] [/tr] [tr] [td]GM T56 F-car After- market[/td] [td] 6.3 [/td] [td]21.5 [/td] [td]27 [/td] [td]21.6 [/td] [td]21.6 [/td] [td]3.75 [/td] [/tr]

 

[Vince'82]

I don't have the measurements for the muncie, but I have the T56 so I can help.

I used a LT1-T56. it's a rebuilt/fixed tranny from an '94 Z28.

It's mounted behind my SBC in my 82.

here, you can see how far is the stock f-body shifter with the stock 77-82 console.




in order to move the shifter in the middle of the stock shifter hole, I would need to offset it 55mm (2.15in.) to the left and 45mm (1.8in.) forward.





you can buy some offset shifter there (previously available from McLeod) :
http://www.hotrodlane.cc/Shifter/shifter.htm

I'm modifying the f-body shifter. I cut it and will use a flat iron (1" x 1/4") and weld it to the two half of the shifter. if needed, I'll add some gussets so the offset shifter won't flex.

/Vincent

 

[KAOS]

thanks for the info guys. I have a few more questions after much late night googling...

Vince...
1. Are you using the 1/2" Mcleod adapter plate to the bellhousing
2. Are you using a stock muncie bell housing or Lakewood scatter shield
3. Is your shifter in the rear most spot on the tranny or is it accessing the shift rail through the tranny's service/access square door that is located a few incher further up from the traditional rear most shifter location?

Hey TwinTurbo...good to see ya again. Yes...to my surprise there are at least 4 different versions of the T56 readily sold and each version has a slightly different shifter location!!! Similar to your diagram posted. Measuring from the front mounting surface directly back to the center of the shifter the measurements are as follows:
LS F-body = 23.9"
LT F-body = 21.1"
GM Aftermarket = 21.6" includes 0.5" adapter plate
Viper = 19.9"

This all makes more sense to me now since I have found some people say the shifter was way off and others have been more lucky similar to Vince's position making the adjustment not all that bad.

I have found a Mcleod bellhousing that replaces the Muncie bellhousing that is about 5" vs. stock 6.4". It says it will not allow the LT1 pull type clutch setup?? but should work with my old Muncie sytle clutch? This would move the tranny a tad more forward also which while probably is not the best for weight distribution/handling but would give plenty of tunnel clearance.

btw.....I found on the Camaro forums where Kiesler in early 2007 had found a new supplier of the Viper T56 trannys but only re-released the T56 conversion to the Camaro folks and decided to not do this for us vette guys. This was all posted by Richard from Kiesler as the Camaro guys were trying to figure all this stuff out how Kiesler was getting the correct shifter position, etc. The Camaro guys did a lot of great research and had it 99% complete on how Kiesler had figured out the shifter position for a T56. Now my thoughts are that if the Camaro uses the same Muncie/bellhousing as a Vette then the shifter position should be exactly the same in position as our vettes and hence Kiesler's Camaro T56 swap kit should work perfectly for our vette's. But I am certain I can get this done for a less monies than what Kiesler is charging and this would be with a SixSpeeds, Inc. T56 beefed up tranny.

 

[Vince'82]

here is my T56 :


I'm using the f-body bellhousing (shorter than a stock bellhousing and adaptor plate) and the pull-type clutch.

here is the f-body shifter :


using the LT1-T56, I was able to reuse my stock TH700R4 driveshaft and slip yoke.

I only needed to modify the crossember (a few centimeters forward and lower than my TH700). I moved the tranny as far up as I could.

if you want to use a push-type clutch, you need an aftermarket T56 or an LS1-T56 with an adaptor plate and a longer pilot bushing. then, you can reuse your stock bellhousing and clutch (as long as your clutch disc is compatible with the T56 splines).

with the pull-type clutch, you need an adaptor flywheel if you have a 2pc rear main seal or you can reuse the donnor flywheel if you have a 1pc rms.

 

[KAOS]

Thanks for the great info and details...much appreciated Vince. I have been doing some more research and found out the following regarding shifter location on 4 speed Muncies (don't quote me on these though as they were pulled from another website):

Chevelles typically had Muncies with shifter location 17.5" from front of tranny
Camaros & Vettes had Muncies with shfter location 19.75" from front of tranny and both have similar offsets of the shifter towards the drivers side

I have a Richmond 6 speed and the mounting location is 20.75" from the front of the tranny and is hardly noticeable the extra 1" further back due to the angle of my shifter stick and the slope downward of the center console. Richmond's shifter is about 2.75" offset to the drivers side from top dead center.

So now the following (preliminary conclusions) on possible combinations with regards to shifter location:

1. Stock bellhousing/Muncie = Shifter is 26.125" (6.375+19.75) from engine block

2. Stock bellhousing/Adapter plate/Viper T56 = Shifter is 26.835" (6.375+0.5+19.96) from engine block = 3/4" further back from stock location

3. Stock bellhousing/Adapter plate/LS1 98+ T56 = Shifter is 30.75" (6.375+0.5+23.88) from engine block = 4 5/8" further back from stock location

4. Stock bellhousing/Adapter plate/LT1 93-97 T56 = Shifter is 30.25" (6.375+0.5+23.38) from engine block = 4 1/8" further back from stock location

Source of T56 dimensions...
http://www.lastofthebreed.com/ServiceInformation/ServiceDocs/T56InstallationDimensions.pdf

Stock bellhousing is assumed to be 6 3/8"
Adapter plate is 0.5"

I now see why Kiesler needed/used only the Viper version of the T56 as this brings the shifter location within 3/4" to stock. They also use a different bellhousing which I assume is less than 6 3/8" which would probably make up for the remaining 3/4" difference then all they would need is the offset to the drivers side. I wish I had access to a Muscle Car shop or owned a Camaro then I could easily compare the Camaro's vs. Vette Muncies and shifter location as I am willing to bet that Kieslers Camaro T56 kit would fit the C3 vette without any major problems. They re-introduced the Camaro T56 setup in early 2007 after they found another Viper T56 supplier but never did this for the C3 vettes which leaves me to believe they had some research & development costs to recoup when they introducted the TKO's kit for C3's after the Viper T56 was not available so that is why they have not offered the T56 kit for our C3's.

 

[KAOS]

I spoke with Mcleod today and they have a new modular bellhousing that replaces the stock Muncie bellhousing and eliminates the need for the adapter plate retaining the old mechanical style clutch. The new bellhousing p/n #

8710-10 for T56 LS1
8710-16 for T56 Viper version
They don't have one yet for the LT1 T56

The new bellhousing is 5.7" vs. the stock bellhousing of 6 3/8" and no need for the 0.5" thick adapte plate so this will essentially move the tranny about 11/16" further forward which is great news for me (I think).

Vince if you are using a LT1 bellhousing then that should be about 4.88" thick? and then with the adapter plate of 0.5" this puts ya at 5.38" vs. me going with the Mcleod bellhousing at 5.7" so I will be about 1/3" further back in shifter location.

 

[BRUTAL64]

I spoke with Mcleod today and they have a new modular bellhousing that replaces the stock Muncie bellhousing and eliminates the need for the adapter plate retaining the old mechanical style clutch. The new bellhousing p/n #

8710-10 for T56 LS1
8710-16 for T56 Viper version
They don't have one yet for the LT1 T56

The new bellhousing is 5.7" vs. the stock bellhousing of 6 3/8" and no need for the 0.5" thick adapte plate so this will essentially move the tranny about 11/16" further forward which is great news for me (I think).

Vince if you are using a LT1 bellhousing then that should be about 4.88" thick? and then with the adapter plate of 0.5" this puts ya at 5.38" vs. me going with the Mcleod bellhousing at 5.7" so I will be about 1/3" further back in shifter location.

Did you talk to George??

 

[KAOS]

Don't know who it was at Mcleod but he was very helpful....

btw...this T56 is a real long transmission so besides my shifter location concern my other concern is the the tailshaft end clearance to the tunnel.

 

[Vince'82]

Vince if you are using a LT1 bellhousing then that should be about 4.88" thick? and then with the adapter plate of 0.5" this puts ya at 5.38" vs. me going with the Mcleod bellhousing at 5.7" so I will be about 1/3" further back in shifter location.

you don't need any adaptor plate when using an LT1-T56 unit with its LT1 bellhousing with a small block (or big block). bellhousing bolt pattern is compatible with old engines. you only need a conversion flywheel (I went with a fidanza alu flywheel).

I don't remember bellhousing thickness but can measure it saturday if you want.

if you go with new mcleod's bellhousing and a LS1-T56, you cannot use you mechanical clutch as there is no provision in front of the tranny for fork pivot ball. you have to use an hydro throwout bearing. I'm not sure if you can use an f-body unit or need to go with a mcleod one ($$$).

 

[Vince'82]

btw...this T56 is a real long transmission so besides my shifter location concern my other concern is the the tailshaft end clearance to the tunnel.

my transmission is so high in the tunnel it needed a few hits with a big hammer near to the yoke (passenger side).

 

[KAOS]

my transmission is so high in the tunnel it needed a few hits with a big hammer near to the yoke (passenger side).

Ahh....that was not what I was hoping to hear but I think I can get around this. At the very least this answers my question that I need to use the GM T56 version which is 3" shorter in length.

 

[KAOS]

Vince....I am totally new to this stuff so what exactly is required to make the LT1 pull style clutch setup work with our old Z-bar mechanical clutch?

I have come to the conclusion that there is basically 2 main ways to get this swap done the easiest...

1. Use complete LT1 stock bellhousing/clutch/special flywheel/T56
or
2. Use aftermarket Mcleod bellhousing/clutch/Viper T56

The first option drawback is the shifter location which is not all that bad I suppose after a few console mods and offset sifter (don't know how hard it is to convert the clutch setup). The Viper option gives me almost perfect shifter location but the Viper is 3" longer than the GMT56 so I very concerned about tunnel clearance.

 

[KAOS]

Vince...I found out from another C3 guy with a T56 in England that there is some sort of Chrysler auto slip yoke 30 spline that is 3/8" narrower in diameter using 1310 u-joints compared to the standard yoke size on the T56's that seems to do the trick on getting more tunnel clearance. I am going to try and get the exact part number and info where to buy.

 

[KAOS]

found it...here is the yoke that anotehr C3 is using that gave him the extra tunnel clearance needed.

CHRYSLER 727 AUTO & A833 MANUAL 30 Spline 1310 Series $59.95

http://www.dennysdriveshaft.com/html/slip_yokes.html

I am 99% certain that I will be going with the Viper & internal hydraulic setup with a master cylinder mounted on the firewall using a bellhousing adapter that is 5.55". This should simplify my install (hopefullY). Now I need to determine what clutch setup I want.

 

[Wesch]

Hi

I found out from another C3 guy with a T56 in England

Not from England, but from Luxembourg , main land Europe.prrtt:
Small country between Belgium, Germany and France.

The 1310 Slipjoke is only 3 1/4 " wide where the 1330 or 1350 slipyoke is 3 5/8 " whide.
As I already said, an other member used the 1330 or 1350 and it did hit the tunnel wall. After contacting me and using the 1310 , it cleared.
I was some kind of forced to use the 1310 because of the 68 Vette originally using this also for the drive shaft.

Don't forget to install a 4.11 or shorter gearset in the back as otherwise you can not use the 6th gear 0.5 : 1. With 3.70 rear, it runs nearly 90 MPH at 2000 RPM. 2000 RPM is not enough for a L71 engine as the ignition timing is not in high power preignition position jet.

Good luck with the install and having a 6speed in a C3 is just cool.

Rgds. Günther

 

[Wesch]

Hi again

Here some pics about the size difference between the GM T56 Viper tranny and the M21 close ratio.

Rgds. Günther

 

[Wesch]

Hi

Here the pic with the shifter position of the T56 Viper tranny. Not realy OK. Too far to the left.

Here the dummy shifter I made up to find the correct position.

And here the original 68 manual T-handle shifter welded onto a adaptor and boltet to the T56 offset lever moving the shifter to the exact correct position.
There is absolutely no slop or bending in this offset lever system. I can not feel any drawback to a straight one at all.

Here you can see how far back into the narrow area of the tunnel the T56 Viper slipyoke moves.

Günther

 

[Wesch]

Hi

One more thing.
To energize the reverse lockout solenoid, I connected it to the brake switch. So I need to push the brake pedal in order to engage the reverse gear.

I was thinking about installing a micro switch into the 68 manual shifter T-handle, so that lifting the T would energize the solenoid.
Any thoughts ?

Günther

 

[Wesch]

Hi

I bought the GM t56 Viper tranny as seen on the pics ( without slipyoke ) from D&D Performance. Don Walsh was my contact man.
Not easy to get into contact with them, but once you are, great people.

I also had to get a complete clutch setup because the T56 is using a different input spline ( 26 spile ) than the 68 M21 ( 20 spline ) , so went with the Centerforce Dual Friction Clutch. I am so far happy with it.

And last but not least, the GM T56 Viper tranny has a mechanical speedo output. You can use the original M21 plastic drive gear and original mechanical cable as is.:bounce:

Günther