84 GMC C2500, V12 powered

[locomotive breath]

Looks like you and Rap-Em-Pappy had a great time, wish I could have made it.

[rod86]

Originally Posted by AceX

That's my buddy Charlie's car. Alot of engineering went into that thing...

yea, i heard it got sold to someone in the states..

[Palf70Step]

Whoa! That will get you some looks. Hot Wheels are alive!

[Rap'em Pappy]

Locomotive Breath I wished you could of made it to the get together. We talked V12's all day and night. You could of gave Rap'em Pappy a drive. It is running real smooth. I let Cayoterun take her for a cruise. First person other than me that has driven it. Don was amazed what I did with his pile of old
iron. I am also amazed it came out that good my self. I would hate to count my hours.
I will be going to Chicagoland Nationals Sept 16-19 next. I am thinking of running with the hood off for that. That is to keep people from falling off there chairs trying to look under the fender. It has happen!! The best part of the trip was putting the two longnoses head to head. Thank you Cayoterun The
pictures came out great. Your next project truck looked good and solid, go for it.....

[cayoterun]

IMO, This is the best part about this truck: We wonder where our project names come from.
Rap 'em Pappys tailgate says it all. The name of the plane was "Rap 'em Pappy". Bob's uncle was co-pilot. On the 19th or 20th mission over Germany, she was shot down. After his uncle jumped, he was never heard from again. Quiet a tribute!!
Cayoterun

[jb1016]

Wow, what a story. Very cool tribute.

[cayoterun]

I'm getting some parts ordered and gathered up. I'd like to fit all adapters and tranny while the motor is still in the stationary stand. Then bench run them.
I'm going to gamble on a 700-R4, since this truck isn't going to be hammered around. It's from a '91 Chev 1500.

Dumb questions:
1: What function is the 12volt wire going to the tranny?
2: Can it be spliced into any 12v source when ignition switch is on?
3: What happens if it's not hooked up at all?

Thanks,
Cayoterun

[spudz]

Nice!!!!!!

[bluex]

Read through this, should help you answer any 700r4 related questions.

http://700r4.com/faq/faq.shtml

You also need a vacuum switch, which should be on the firewall of the donor truck. This will unlock the converter allowing the trans to downshift when you step on it. Or you can avoid all this and buy a non-lockup converter and be done with it.

Bowtie overdrives is a great source for 700r4 stuff. I purchased my TV setup from them when I converted my '78. Great customer service and they really know these trannys.

[cayoterun]

Thanks for the additional info. Your post came in while I was replying to Steemin Ehman.
This is the first time in my life I have ever tried to understand an auto. Always took them to a shop if they didn't work.
Teaching an old dog new tricks is hard.
Cayoterun

[cayoterun]

Originally Posted by bluex

Read through this, should help you answer any 700r4 related questions.

http://700r4.com/faq/faq.shtml

You also need a vacuum switch, which should be on the firewall of the donor truck. This will unlock the converter allowing the trans to downshift when you step on it. Or you can avoid all this and buy a non-lockup converter and be done with it.

Bowtie overdrives is a great source for 700r4 stuff. I purchased my TV setup from them when I converted my '78. Great customer service and they really know these trannys.

I got the motor and tranny crossmembers and mounts in place and motor mounted in frame.
Now I'm back into the 700R4 classroom. I am reading and rereading the info. from earlier posts.

BlueX: If I used a non-locking converter, What functions do I lose, and does this eliminate the electrical wire-ups for the tranny?

I understand that the TV cable will always be needed and well adjusted.
Thanks,
Cayoterun

[cayoterun]

Felt good to sit the good motor in the frame. Hope it don't have to come back out anytime soon. I'll be hassleing you guys with more 700R4 questions now for awhile.
I left the irrigation control panel on the motor so I can hook battery/ fuel to it and run in frame as we go along. I may hook up a temp radiator.
If I put the cab back on the original mounts, it looks like the firewall will be about halfway between the carbs. May have an air cleaner on the inside of the windshield. Time will tell.
The weight of the motor only dropped the frame to ground clearance by 1-1/2inches. Was glad it wasn't more.

Cayoterun

[bluex]

Originally Posted by cayoterun

I got the motor and tranny crossmembers and mounts in place and motor mounted in frame.
Now I'm back into the 700R4 classroom. I am reading and rereading the info. from earlier posts.

BlueX: If I used a non-locking converter, What functions do I lose, and does this eliminate the electrical wire-ups for the tranny?

I understand that the TV cable will always be needed and well adjusted.
Thanks,
Cayoterun

I believe that will do away with the electrical portion of the swap. You will only lose the 4th gear lockup which gives me about another 3-400 rpm drop when crusing the highway. The lockup does away with any and all converter slippage at crusing speed. You will still get the OD, but will lose just a little without the lockup. I am not an expert on this but its really not that hard to wire up. BTO helped me out alot with my swap and with their help and TV kit, I have not touched any of the settings in 8 yrs. Give them a call I'm sure they will be glad to help you and give you definate answers....

Motor/trans looks killer in the frame. I say section the cab and have it riding inside with you!

[cayoterun]

Tomorrow may be the day I chain "Doc" down to the tractor and pickup, with the rear wheels blocked off the ground and static run it. Don't plan to run motor more than 800-1000 rpm max.
I did put a Bowties overdrive shift kit in the 700R4.
I only have a temporary elec. on/off switch hooked to the tranny.
I have the tv cable hooked up, and adjusted according to the instructions in the factory shop manual. At least close, I hope.

Some questions:
1: On startup and idle speed the elec. switch should be on, correct?
2: After light acceleration, and the tranny shifts thru the gears and into overdrive, I then turn the switch off, so it will fall out of overdrive when I reduce rpm. When it drops out of overdrive, then turn the switch on as long as it's in lower gears at lower rpm.
3: If all that works ok, then I'm not at risk of ruining the tranny?
4: Is it ok to manually shift the tranny in each gear with shift lever? If I do this, does the switch need to be on or off?

Thanks,
Cayoterun

[steemin_ehman]

Heres some good info as well:

http://www.73-87.com/7387garage/drivetrain/lockup.htm
http://www.purplesagetradingpost.com...o/700R4p1.html

[cayoterun]

Thanks, Guys:
Great info.

I may not get a wink of sleep tonight. Learning alot tho.
Cayoterun

[cayoterun]

Printed off alot of the info. in the links. Lots of good stuff. Sure helps.
Thanks for posting.
Cayoterun

[cayoterun]

Been studying the info. printed from the links.

Low vacuum switch? How important is it for my use? As said before, my torque is 630#@2400rpm max. It will take a hard load or quick stab on the throttle to drop my vacuum much. From the info, I understand the most important thing about all these controls is to get the torque converter to unlock in 4th (od)? If so, I can deal with that by manual shift to 3rd with shift lever. In short, stay out of 4th except easy hiway driving, since that is the only time I want od.

I think I understand what's necessary concerning the TV cable and carb bell-crank adjustment and can get there by using a pressure gauge. Also understand the need for the brake switch to kick out of od. I have to fabricate the bell crank for the propane carb and and cable mount on block. The measurements needed were in the links. Thanks to you guys and the links you've posted.

The motor and all are still in the donor '91 GMC truck, so if I can trace the wiring, switches, etc and get them removed intact, then try to copy it on this motor, except necessary adjustment changes it will create.

I'm just puzzled how I can deal with lack of quick vacuum changes, if staying in third except on hiway won't protect the torque converter and tranny.
Cayoterun

[jeffspower]

Plenty of people will say "oh no, don't do that" but...

If you don't want to hassle with all of the electrical stuff- don't. You can put a 1/4" checkball under the lockup solenoid and it will lock under load late in second gear, giving a direct coupling feel like a manual trans as it shifts up thru 3rd & on to 4th. It will unlock on it's own on deceleration. I've done this many times including one behind a 6.2 diesel, and 500 Cadillac in heavy pickups pulling a 7,000 lb. trailer. It doesn't work worth a darn behind a low torque engine, as there is no torque multiplication when locked. Doing it this way will give a shift feel kind of like the old 4 speed Hydramatic had... remember the chug you would feel on the 2-3 shift with those?

I've only done this on the 1990 and older 700R4, not the 1991- up 4L60 which was computer controlled. I'm not sure if you can checkball the latter.

[steemin_ehman]

Theres a plastic gear drive system adaptor to replace the electronic speedo sensor. you remove the tailshaft housing, pop off a retaining clip, remove the stuff for the electronic speedo, and install a plastic gear style one in place. Very simple to do, the hardest part is knowing whether you need a 34-39 series, or 40-45 series.

40-45 series:
http://www.bowtieoverdrives.com/cata....php?ITEMID=14

34-39 series:
http://www.bowtieoverdrives.com/cata....php?ITEMID=19

Bowtie Overdrives is a good place to get information and parts. You can also get different speedo gear ratios to factor in rear end ratio, tire diameter, etc to make your speedo accurate.

[steemin_ehman]

found another great site:
http://texasz.net/allan_and_rosanne/...nformation.htm

it has more information pertaining to the series you'll need (# of teeth on drive gear), as well as other things that are helpful to know regarding the swap.

[cayoterun]

Lot's more great stuff. Printed it all off to take with me with the other info to study while gone.
These computors are great stuff, if you know how to use them. I don't! You guys are a great help. May check in now and then if I can find a computor while down there.

Need to go to Ark. due to family illness for a week or 10 days. Hope to find things much improved, but news now not the best. Nephew has a brain tumor.
Thanks,
Cayoterun

[dabels23]

Hope your nephew gets better!

I love the project!

[cayoterun]

Looking toward 2011, Since last post in Oct., things has been hectic in my wife's family.
Lost a nephew and bro-in-law, Funerals same day. It's said that it's darkest before dawn. Hope so.

But in our 5,500 miles, we have gathered some parts, and was good to be in the shop this evening, lining up, checking fit, and dreaming.

Looks like we have a complete drive-line except shaft.
Flywheel cover adapter:
Flywheel/Flexplate adapter: designed and machined by Locomotive Breath
3.42 14 bolt rear end: Bartered from Locomotive Breath
700-R4 tranny:

At 2400rpm, that combination should give us around 90mph, which is fine with me. If we can run 70mph around 2100, that would be great.
Now, if I can get it set in the '84 frame and all adjusted, then we can decide whether we make another long-nose, cut the firewall and let motor back in the cab, or what.
We did get the '84 titled, and current tag on it.

Happy and prosperous new year all, and help me build a truck.
Thanks,
Cayoterun

[locomotive breath]

Sorry to hear about the family. Never a good time to lose loved ones but this time of year seems to make it even tougher.

Glad to see your getting back out in shop. It's always the best therapy for me.