Replacing 4sp manual with 700r4 question

[9teen69]

Getting ready to swap my muncie for a 700r4. What all do I need?
Parts I already have:
rebuilt 700r4
torque converter
flexplate
crossmember from an auto truck
auto brake pedal
linkage

Talked to the guys from bowtie overdrive and I'm going to get the TV cable and lockup from them. They told me I need to crack open the tail and find out what type of speedo gears are in there.

Where can I get a speedo cable?
Also a little confused on what to do with this two piece driveshaft.
If I buy the pre-bent transmission cooler lines from LMC will they work?

Thanks for any advise.

[leddzepp]

I have the stock speedo cable hooked up to my 700R4

[Tx Firefighter]

If you have a stock type of standard transmission starter, you will need to either change the nosecone of the starter or replace the starter entirely.

The original standard trans starter bolted to the bellhousing not the block.

I usually just change the nosecone of the starter. You'll need the two new starter bolts too if that's the case.

[70GMCer]

I'm not sure about the 4spd length, but the 350 turbos w/6" tail shaft & the 3spd manuals are 3 inches shorter than the 700r4. So, you will most likely have to shorten the front drive shaft.

[Wrenchbender Ret]

You can use the same speedo cable. You dont really need to change the inner gear. After you get in running compare the odometer miles with the mile markers on the freeway. You can get gears with different amount of teeth to correct it.

[cparman]

my 69 went from 3 on the tree to 700r4. I bought :
700r4
flex plate
converter
replacement crossmember
cooler lines from in line tube
had two piece driveshaft shortened about 3 inches
used a high torque mini starter for additional clearence between exhaust and starter
did not change the drive gear ( one on the output shaft of trans ) was able to get a driven gear that made speedo read correctly
I also used two pressure switches that are screwed into the valve body of the trans to lock up the torque converter in both third and forth gear. Do not like the lock up in third, and will go back when I get to it.
Used a stop light switch from a late 70's early 80's caprice with cruise control to unlock the converter with the brake switch. The 4 wire connector in the trans is labeled A B C D. My brain is flat tonight but I think it is the A terminal that needs 12 V to lock up the converter.
I also used a LOKAR TV cable for ease of adjustment ( have used them before. Also bought LOKAR's carb bracket to mount the other end of the TV cable. I love the setup, and it works great.

[VetteVet]

More Info:
http://67-72chevytrucks.com/vboard/s...ad.php?t=33266

[9teen69]

Totally forgot about the starter.
Do ya'll know if the kit from bowtie overdrive comes with connection to the 4 wire plug?
Sounds dumb but where does the speedo cable go... is it where the big round hole in the tail is from my first pic? If so I don't see how the original cable can work.

Thanks

[cparman]

you need a speedometer drive gear housing for the hole you speak of. I am not sure on this site, but there are sites that you can plug in your rear end ratio, tires size and it will tell you what gear you need. You might try NAPA for the connector. If they do not have one, ask them who in your town sells AC DELCO parts. they will have the connector you need. the local GM dealer might also be able to get the connector. If you cannot get this stuff. PM me, and I should be able to get all of it here in JAX FL

[9teen69]

Thanks, I have 3.73 gears and am running 275x60x15 tires.

http://www.73-87.com/7387garage/drivetrain/speedo.htm

The drive gear in my tranny looks green. So according to this site it looks like I need to replace it with a gray 15 tooth gear - does that sound right.

[cparman]

I looked up the NAPA part numbers for the connector, and the stoplight switch.

STOPLIGHT SWITCH : SL186
TCC CONNECTOR : EC79

Now I also called my local chevy dealer, and got a part number for the drive gear housing..25007308 If there is a delco supplier in your town they can get this instead of going to the dealer. It is a bit pricey 50-100?

This housing is for a BLUE or GREEN drive gear. Not the gear on the trans shaft. do a bit of homework about these two gears, and make the change before you install the trans. There is a fussy little clip that hold the gear on the shaft, and with the trans on the floor you can see it to remove it.

HOPE THIS HELPS

cHIP

[9teen69]

That's awesome, thanks for the help!

Where is a good place to get trans cooler steel lines, sure I can get a trans cooler at a local parts or napa dealer? If I ask for stock lines for a 350 or 400 will they work?

[cparman]

I do not want to step on a site vendors toes, but I have used INLINE TUBE for cooler lines and brake lines. They will have a listing for cooler lines for a 700. Does your radiator have an internal cooler? If it does run one cooler line into it, and let the fluid come out of the internal cooler and go into the external cooler then back to the trans. It will help keep the trans fluid at a consistant temp. IF YOU DO NOT HAVE AN INTERNAL COOLER. I would get a big plate type cooler from NAPA, and just run the fluid thru it.

[9teen69]

Do I have to remove the cross member the old manual transmission sits on? If so, how?

[Tx Firefighter]

Yep, that old crossmember will have to go. It's riveted in and can be a pain to remove. Some guys torch them out, some guys remove the rivets. It all depends on your level of OCD.

Myself, I remove the rivets with a grinder and sawzall to save damage to the crossmember so it can be resold to someone who wants it.

[Tx Firefighter]

By the way, you don't need a brake pedal. Your original brake pedal is the same one used in auto trucks too. You simply remove the old clutch pedal and linkage under the dash, leaving the brake pedal alone.

[Jtrux]

I kinda glanced through all the posts and didn't see anyone say anything about a new steering column unless I completely missed it.

Good luck with the install, sounds like it will be a lot of fun afterwards.

[9teen69]

Figured I had to remove, think I'll have to grind it - cool another tool I need to buy. Bummer, I already bought an auto brake pedal. Working on buying a column from a board member in a few days. Thanks for all the help.

[Mike C]

Edited by Mod.

[cparman]

I bought one of the crossmembers that will allow putting the exhaust above the x member $100.00, I intend cutting the holes larger in the rear crossmember and run the exhaust thru it, to get the exhaust as high as I can. I used an air chisel with a sharp chisel in it, and cut the heads off of the rivets, then took a punch and knocked out the remains. The x member that I used has 6 bolts per side to bolt it up. Drilling the holes, and removing the old x member was the most work.

[9teen69]

Bought a 3" pneumatic cutting wheel from Harbor Freight today for $7 bucks -hope it holds up.

[9teen69]

Well, it's been awhile but I have the tranny and crossmember in place. I had to drill new holes in the frame - hated doing that.

Worried about clearance. Question: I only have about 1/4 of inch between the back of the pan and the x member. Is that going to be a problem?

Progress: The column is cleaned up and ready to go in- the new rubber boots were a booger to stretch over the linkages, the new pedal is installed. Adapters installed on carb. Bowtie overdrive was helpful with parts and tech support. Need to run to the store for some shorter bolts for the x member. Waiting for a part I ordered for the pushrod to pedal. Need to measure the D/S, thinking of going with a one-piece. It's getting there - hope to get it down with my 16 and 17 yr old help during spring break.

thanks

[Andy4639]

Yep that cross member and pan are close. Mine is the same way. If you ever drain and pull the pan guess what...you have to unbolt the C/M and slid it back. I cut 3 1/2 " out of my front half of the drive shaft. Transmission lines are the same I'm pretty sure.
Most original transmission cooling line sets will work just fine once they have been "reshaped" slightly to line up with the fittings at the transmission end.

[9teen69]

Thanks for the info. Yeah, I should install one of those quick drain plugs.

[9teen69]

What year do I need to tell the napa/auto part guys so they order the correct dip stick and flexplate cover?

Hope to wrap this install up the next week since my two teenage boys are on spring break.