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Wanted: 4 Speed Conversion Experts ...


Mike Brichta

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Hey Guys,

 

I managed to find and purchase a 4-speed donor car last weekend. Now don't panic, the body was totally gone but the car ran and drove and is complete. I would never part this car out if there was any way of saving it. The donor car is a 70 El Camino (non SS) with a factory 350 4-bolt main engine, Muncie M21 4-speed and 12 bolt rear. I purchased the car without the engine because the owner wanted too much for it and I don't need another engine. Everything else is on the car. I am planning to convert one of my current Montes with TH350, 12 bolt rear to a 4-speed car. I have never had a 4-speed car nor have I ever converted one so any suggestions, tips or help would be appreciated.

 

After doing some research I believe I only need to purchase (2) items so far.

1) The Z-bar frame mount bracket on a 70-72 Monte is different from a Chevelle/El Camino bracket. Is that correct? I have yet to locate one so if anyone knows where I can find one let me know.

2) The M21 Pilot Bushing that goes into the back of the crankshaft. I forgot to take it from the engine when it was pulled.

 

Before I start pulling things apart I am trying to put together a list of things that might work and others that might give me trouble later on.

 

Here is a list of what I think will work:

- Bellhousing, fork and throw-out bearing should work

- Flywheel and clutch should work

- M21 and all linkage should work

- All of Z-Bar (except frame bracket) should work

- Shifter and console should work

 

Here is a list of things that I am unsure of at this time that might give me trouble:

- Driveshaft might be different (El Camino M21 12-bolt vs Monte TH350 12-bolt)?

- Neutral Safety Switch, linkage and wiring?

- Ignition Lock-out mechanism?

- Backup Light wiring?

- Speedometer Cable different?

- Steering column different?

 

This is going to be my Fall/Winter project so I can take my time getting it done. If anyone knows of something I am missing let me know. Progress updates will follow.

 

Thanks!!

Mike

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Congratulations, Mike!!  Glad you landed that manual drivetrain - sounds like a great winter project!  I love my 4-speed '70 but can't speak to the conversion process.  Fortunately, there are several members who have been down that path or otherwise know what it takes.  I know Murray (Murphy) had done the conversion recently.  Sam (Bones) and Darren (LS5) know what it takes, also.  I'm sure they will be glad to help you get it sorted out!  Good luck finding the missing pieces and let us know how it goes.

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Morning Mike, Just a quick reply I will chip in my 2 cents Pal I just got some running around to do and will reply a little later. quick thoughts are Z Bar bracket IS different for sure, There is a guy on Ebay that quite a few of us have bought from his name is Mike and goes by the Ebay Name of Sonnie24 he sells lots of Chevelle/ Monte Cralo/ Elky stuff and he sells our tach and gauges and also Clutch components even the Z Bracket you seek. will get back to you on a list later on what to keep off elky 

Maybe Sam and Murphy will chip in as well

****** I have a spare Dowl for the back of the crankshaft for the M21 if you need one*****

 

 

Here is a list of what I think will work:                        

- Bellhousing, fork and throw-out bearing should work                                  YES
- Flywheel and clutch should work                                                               YES
- M21 and all linkage should work                                                                YES
- All of Z-Bar (except frame bracket) should work                                        YES
- Shifter and console should work                                                               YES

Here is a list of things that I am unsure of at this time that might give me trouble:
- Driveshaft might be different (El Camino M21 12-bolt vs Monte TH350 12-bolt)?           Different
- Neutral Safety Switch, linkage and wiring?                           SAME & KEEP STEERING COLUMN AS WELL
- Ignition Lock-out mechanism?                              A Different bracket on frame for monte    MIKE Sonnie24             

- Backup Light wiring?                                    WILL WORK
- Speedometer Cable different?                      TAKE FROM ELKY ITS THE SAME
- Steering column different?                              SAME TAKE

 

 

Darren

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Good morning Mike, as Darren mentioned, he is right on the mark. The drive shaft in your Monte will work if you use in correct bellhousing. Definitely get the u joints replaced and shaft Rebalanced. The crossmember is actually different but I used my stock one and drilled additional holes in the frame for mounting. Also will need new trans mount. Good luck, you'll love it!

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Update: I managed to get the trans out last night. I verified all of the numbers to verify it is a M21 Muncie 4-speed. The flywheel was even stamped with a date in 1970.

 

As I gather up all of my info, I put together (3) lists that I need to deal with. All suggestions are welcome.

 

Things to Do Yet

- Remove Speedometer cable (looks longer than a Monte one)

- Remove Pedal Assembly

- Cleanup Trans, Bell Housing, etc.

- Look at removing Hump and location

- Get pictures of Axel Codes (12 bolt - 3.31 open)

- Remove and check out Z-bar assembly

- Start folder to save all progress and info

 

Things to Get

- Frame bracket for Z-Bar assembly (3972641 MT2108M)

- Frame Bracket for Ignition Lockout assembly

- Clutch Lineup tool

- M21 Pilot bushing for end of crank

- End of rod that goes into clutch fork (appears to be missing/broken)

- New U-joints, new trans mount

 

Questions

- Reverse Light wiring (just supplys ground)

- Neutral Safety Switch and wiring

- Torque Specs

o Flywheel Bolts (60?)

o Clutch Bolts (45?)

o Bell Housing bolts (??)

- Which driveshaft to use (I’m thinking the Monte one)

- Which Flywheel to use (original is pitted – can it be smoothed or just buy new)

- Different humps for console vs non-console cars

- Should I have someone check out the trans before putting it in (gaskets, seals, etc.)

 

This is getting exciting. More updates to come ...

 

Thanks!!

Mike

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Hi Mike, see answers and suggestions to your questions:

 

Things to Do Yet

- Remove Speedometer cable (looks longer than a Monte one) YES a 4spd cable is quite a bit longer.
- Remove Pedal Assembly....... Take whole assembly not just pedals, the set up unbolts from the firewall from the 4 nuts that hold on the booster on and the main assembly is what holds the pedals up in place. The reason I say this is because the 4spd set up will already have the neutral safety switch holes pre drilled and switch should be inside elky already. plastic will be brittle so dont try to pop switch off as new ones are $300 just for switch. 
- Look at removing Hump and location.....Yes a Bench seat hump and a Bucket seat hump are different and so are the Muncie Shifter handles. Benchseat handle and buckets handle are way different.

Questions
- Reverse Light wiring (just supplys ground)...........Yes
- Neutral Safety Switch and wiring.............YES should be in El Camino if not your monte wont have it and then it's Ebay Time..
- Torque Specs......... Google search as well as Team Chevelle will have those specs
o Flywheel Bolts (60?) ................... Napa Or Pep Boys
o Clutch Bolts (45?) ....................... Napa Or Pep Boys
o Bell Housing bolts (??)..................7/16ths x 1-3/4..........some are 3/8ths but double check
- Which driveshaft to use (I’m thinking the Monte one)    YES Monte, measure from center to center of U joint to get over all length.
- Which Flywheel to use (original is pitted – can it be smoothed or just buy new)......New One...Napa or Pep Boys
- Different humps for console vs non-console cars    YES as Mentioned above
- Should I have someone check out the trans before putting it in (gaskets, seals, etc.)............. YES check it out

 

 

Darren

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Oh DONT forget the HORNS..... 4SPD horns are different......................

 

Because you will go through twice as many horns than an automatic car as in.." Get out of the way I am coming through honk honk"

 

 

 

hahahahahaha

 

Darren

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Thanks for all of the responses and good info. I think I am making my way through my list but not quite done yet.

 

I managed to remove the steering column, pedal assembly, and speedo cable today. I tested the neutral safety switch and it seems to be working fine. That seems like a pretty crappy switch IMHO, especially since it determines if the engine will crank or not. I'm going to keep a jumper wire in the car just in case. Everything seemed to come out as expected.

 

I did see something that kind of puzzled me. Even though I have a neutral safety switch on the clutch pedal the steering column still has one on it with a plug into the harness. Does it even do anything or is it just a place to hold the plug?

 

I also had a question about the ignition lockout switch and assembly. I could not test it before I started the project because the engine was removed from the car and some of the linkage was loose. My question is what position does the shifter have to be in for me to completely turn off the key and remove it from the ignition switch in the column?

 

Thanks!!

Mike

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 My question is what position does the shifter have to be in for me to completely turn off the key and remove it from the ignition switch in the column?

 

 

Reverse (if an El Camino is like a Monte).

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 My question is what position does the shifter have to be in for me to completely turn off the key and remove it from the ignition switch in the column?

 

 

Reverse (if an El Camino is like a Monte).

 

 

You Betcha thats it......... Reverse Lock out, meaning it locks out in reverse now releasing the ignition key when the sleeve on the column is turned all the way.

 

Some Muncie Tranny's have the sensor in the casing for the reverse lights to be activated and come on and some have them activated from the steering column from what appears to be the Neutral switch.

My 1967 Chevy Shortbed that has a Factory 327 M20 4spd does just that, the casing has no sensor and the column triggers the reverse lights.

 

Darren

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Well I think I'm getting closer to a solution but not quite there yet. I have (3) switches in question.

 

1) The neutral Safety Switch on the clutch pedal. I'm pretty sure I know how that works. I just need to wire that into my car. I have to say that the original switch looks kind of like a future point of failure. It looks flimsy and is almost 50 years old. I'm hearing that they are $200+ for a new one. That ain't going to happen!! Does anyone run their car without one? I read that they didn't actually start putting these switches into use until 1969 so a 1968 car did not have one? Anyone else come up with a better solution like maybe using another less expensive switch?

 

2) The reverse light switch(s). It would appear that my car has at least (2) switches to make the reverse lights work. One is on the transmission and the other is on the steering column and they both have plugs on them that go into the harness. I guess it doesn't hurt to have more then one because it only supplies a ground to make the lights work. Do I need both? I would rather not use the one on the transmission and just use the one on the column. Will that work?

 

3) Mystery switch. There is still yet another (2 prong) switch on the base of the steering column. It has a plug that goes into the harness but for the life of me I can't imagine what it would do. Does anyone have any ideas? I have already ruled out the Neutral Safety Switch, the reverse lights and the turn signal/flasher plug on the column. What else is there?

 

Thanks!!

Mike

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Mike,

 

I might be able to answer a couple of your questions:

 

1) My '70 4-speed came to me with the NSS jumpered out of the circuit.  I didn't even know it was supposed to have one until a friend pointed it out.   I ALWAYS engage the clutch before touching the ignition key, but it might be good to have.  I get really frustrated with all of the safety lockouts on modern cars so this may be where it began.

 

2} Don't know how many reverse light switches my Monte has but the lights are on in reverse when the car is running.  I could study my  '70 wiring diagram to see if there are multiple switches.

 

3) The TCS solenoid switch is shown on the wiring diagram.  It is necessary to sense when the car is operating in 4th gear.  I am pretty sure it is the unconnected sensor on the driver's side of my M20 case.  In any case, there were only a couple of remnants of the TCS apparatus on my Monte when I bought it and it is not likely to ever be complete or operational while I own it.

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Mike, my 71 was a column shift automatic, I have not swapped the steering column (yet),but I wired the shift lever at the bottom of the column so it is always in PARK. I did not install a reverse lockout either. I'm the only driver of my Monte so depressing the clutch pedal at start up is natural for me growing up with manual trannys. I installed a new Hurst shifter and purchased the Hurst reverse light switch that mounts on the linkage,so wiring to the connector on the column was cake.

I`m currently on vacation in Branson,MO but when I get home I can send more details with photos....Good Luck! Murphy

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