Re: GMC V-12 powered '91 Chev crewcab
 

i sounds good , i do notice that one of the exausts is blowing a little more smoke then the others

Re: GMC V-12 powered '91 Chev crewcab
 

I don't know what to expect from it. About anything might show up. When we get some kind of cooling hooked up, we'll learn more.
I sure want to put some hrs of run time on it in the stand before going too much further.
The length of this video is the longest it has run, and we thought that was plenty.
Thanks,
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

I'm about to utter the phrase that usually ends up making me broke...

I want one!

Re: GMC V-12 powered '91 Chev crewcab
 

I'd still like to see someone build a T-bucket type rig that has the motor exposed.
Keep thinkin', Storm-Chaser
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

Heh, my thinking gets me into trouble... I'm currently working on a picture of a late 30's-early 40's military truck with an Airstream camper attached. It's just for fun though, I don't plan on building it.

Funny thing... about 3 years ago I toyed with the idea of welding a CJ5 front tub to a CJ7 rear to make a 4-door Jeep... Now you can go to the dealer and get one new. I also wanted to put a VW body on a Jeep chassis, and have a Chevy V6 hanging out the back (called it Project Cockroach).

But yea, I'd really like to build a T with a twin six someday. If one of those engines ever comes up around here and I can afford it, I might have to grab it up.

Re: GMC V-12 powered '91 Chev crewcab
 

If gas wasn't so expensive, I'd take you up on that. It would look cool as hell in this....

http://www.boomspeed.com/bofh1968/chevy/pic1.jpg
http://www.boomspeed.com/bofh1968/chevy/pic2.jpg

And that thing is still parked out there, so I could probably get it relatively cheap now.




You're giving me ideas here. STOP THAT!!!!! :hm:

Re: GMC V-12 powered '91 Chev crewcab
 

That thing is going to have an awesome sounding idle. I bet with full exhaust and a good tune, it will be smooth as silk at less than 400 rpm. Sounds pretty responsive for having a crankshaft & flywheel that weighs more than some of today's complete engines!

Re: GMC V-12 powered '91 Chev crewcab
 

That is just GREAT!

Re: GMC V-12 powered '91 Chev crewcab
 

The only new parts I put on the motor were both distributor caps , rotors, propane diaphrams in carbs, and gaskets/w a used head.
I did that for braggin' rights on behalf of their durability.
Today, it got new coils, points, & condensers. I didn't put any themostats in it, hooked up a garden hose, ran another hose from water pump out door. Circulated clean water thru it for about three hrs. Lots of rust and junk came out.
I have 10-30 oil in it, thinking that might go thru oil passages better. They normally run 15-50 in them. I don't plan to wind it up much for awhile, then change to heavy oil. Timed it with a light, and the longer it ran the smoother and quieter it got. The right front bank has about quit smoking.
Keep thinkin' on those open motor projects.

Fuel consumption: It used about 5 gallons of propane in about 3hr run time. I guess it takes fuel for fire & smoke, tho.
Thanks,
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

I don't know about your specific engine but the other v6's could turn 3k easily. hooking 2 of them together shouldn't reduce rpms. the 2400 may be a max constant rpm. far as the setup for it I was thinking move the cab back so it would fit. modify the fenders and hood so they would reach. gear the truck HIGH these have more than enough torque to pull. Far a a transmission goes check your bell housing bolt pattern. there were a bunch of the smaller v6's put in 1 ton pickups. If you are lucky it will bolt up to a regular gm bell housing. I don't know when GM totally quit making this series of v6 but I know a 478 was available in a 74 gmc 7500 series.

Re: GMC V-12 powered '91 Chev crewcab
 

the latest creeation from the blastolenes has a gmc v12 in it btw
http://www.blastolene.com/b702_f.html
they made the tankmotor powered rod for jay lenno too

Re: GMC V-12 powered '91 Chev crewcab
 

Approximate mileage equivalent. These could be very realistic numbers, annual run time could even be more.
24hrs X 7 = 168hrs per week X 26wks per year =4,360hrs per year X 60mph = 262,080 mi. per year X 21 yrs service = 5,503,680 Total equivalent miles on old "Baluar". No wonder she has a contankerous attitude. So if she drinks oil, rattles, smokes, clunks, and complains, I figure she earned her dues.

Ck my 'rithmatic
We do know it's been long blocked once and probably valves more often.
All motors run much longer pumping than in vehicles.
What is it? Constant rpm, temperature, oil circulation?
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

prolly the fact it runs all the time so no loss of oilpressure on shutdown and startup , it keeps its temperature , and i guess it doesnt had to work over 60 % of its total power driving the pump back in the days

Re: GMC V-12 powered '91 Chev crewcab
 

I couldn't help myself...

Re: GMC V-12 powered '91 Chev crewcab
 

My Gosh--Awsome--wild-- best ideas yet!! Don't paint nutin' but, maybe?, motor?? Can you add 12 chrome stacks? One off each cylinder sticking straight up.
Now, that's my idea of a real hotrod from the '50's. That looks like something straight from 40 yrs in the scrap yard and brought back to life.

If Mama don't take away our ideas and crayons, we'll all be in deep trouble.
If I take some pics today of the trucks, would it better to post them here or send PM, and could/would you tinker with them on this same idea? I'm kinda stuck on my '62 GMC cab (at least) because of the current tag and title.
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

The '62 pickup pic stinks. I'll go take more in the morning. I'll try to get the hood sit on it if the bum back will let me. It was a good time of day for the 1ton.
I'd like to set the cab and front clip from the pickup on the '79 1ton. Slide pickup cab back and extend clip back two feet and use same 1ton flat bed and frame/w bed chopped two feet. That would leave us 2 feet shorter bed and 2 feet longer front clip.
Also, add tool boxs both front & back of wheels under bed.
If someone wants to, tinker with no front clip & open motor.

Someone may ask, why change? Pickup has tag and title and personally, I won't sit the engine on a suspension lighter than a 1ton. When we get the engine, clutch,tranny and all combined, it will probably weigh 23-2400#

Run 2 more hrs on "Balaur" today. Running better.
Thanks,
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

Maybe a better pickup pic w/ hood
Thanks
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

Been doing lots of driving and measureing. Be glad when I get them all drug home.
Back to frames. I know chevy made 3 wheelbase lengths. Standard cab/chassis, 131". X-cab, cab/chassis, long bed, 155".
Crew-cab, long bed dually, 168" + being wider.
Jeff, if I understood you right, then the frames widths are the same from '73-'87. right?
Did they start making x-cabs in '73, if not when, to get the 155".
The '62 GMC, long bed pickup is 127".
I'm pretty sure I want to use the narrow frame and differentials, for the different bed options it would offer.
I'm needing to start calling salvage yards some distance from here, so need to make sure I understand what I need.

"Baluar" has about 15hrs run time, rings and seals seem to be softening and reseating. Used about 25 gallons of propane so far. Still smokes some. Probably always will some, and use oil. How much remains to be seen.
Thanks for all the help
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

Yep '73- '87 are all the same widths. One ton frames are thicker, and have a taller main section height. I'm assuming the 3/4 ton 4dr. does also. I don't think they made a 4dr. till '75. You would definately want a one ton frame, the lighter ones might be too flimsy and do the frame boogie over bumps & expansion joints in the road. I remember guys who had 4dr trucks stretched to make "wedge" car haulers and would get the frame boogie. With that extreme length & weight, the frame channel needs to be boxed in at least from the transmission crossmember on back close to the rear axle front spring hanger.

Re: GMC V-12 powered '91 Chev crewcab
 

My son-in-law and family owns a lumber yard, and they retired a '72 Ford 160" wheelbase 1-ton flatbed delivery truck. Has 11-1/2' flatbed. He wants to keep the long bed for the replacement.
Did some measuring today. Gives plenty of room to slide cab back, and still use my 9' flatbed.
Frame rails and wheel width the same as the '79 chev. An 8' chevy/GMC pickup bed could also be used.
It already has a propane system installed to run the V-12.
The '91 crew-cab dually wheels & frame rails are several inches wider.
Looks interesting, here close, and veery cheep.

Will I be banished from this site to have a brand-X frame and running gear under this?? We'll hide it under all Chevy/GMC stuff.
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

did he just wrote down the f word ............whoooooooo badbadbadbad

Re: GMC V-12 powered '91 Chev crewcab
 

Twin I beam front end, right? I'd pass. Ford didn't get it figured out until the early '80s when they went to welded assemblies with balljoints instead of forged axles & kingpins. And I still don't think the newer ones even come close to as good a design as the GM traditional independent setup. Those old Fords won't hold the road, or an alignment. A Ford pickup from that era with radials & a good alignment drives worse than the same years of Chevy with bias ply on a worn out front end. As bad as they were with ONE six pop in them, I can't imagine what it would be like with the weight of two! I like the looks of the 67-72 F series, but I hate driving them.

Re: GMC V-12 powered '91 Chev crewcab
 

I didn't even look up there, I was just measureing cab-axle, but I had a dose of twin I-beam on a new '74 1/2 ton, and it wasn't good. Don't need no more.
Thanks for the reminder.
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

Frame Stretch?
Not having much luck finding a '73-'87 155" frame.

Was wondering about stretching the '79 131.5" frame to fit the length I need. The frame rails on it are 8" deep.
Will ordinary 7.5-8" channel iron work for the added length or does it take frame metal? I'd fish plate it in addition to the vertical welds.
I know frames have to flex, so didn't know whether it would try to fatigue and break. Any advice?

Have run 80 gallons of propane thru the V-12. She's old, tired, and worn, but runs. Maybe can find a better one someday.
Thanks,
Cayoterun

Re: GMC V-12 powered '91 Chev crewcab
 

Hi, I've been following this thread for months. Here is my take on your truck.