81 Chevy Cummins swap 90% complete

It's not a blazer its a silverado. I already new I'd need a dana 60 for the the rear, and I want one with a 14 bolt with 4.56 gears since I plan on putting 37's on it. That's why I'm wondering is it cheaper to get an old cucv or just keep the free k10?
 
the D60 might be expensive to acquire seperately but you should be able to pickup good, complete, ready-to-run 14BFF for $500-$750 depending on how good of condition it's in. If you can get a CUCV for cheap, it's a good start. Some extra work with the wiring though since they are 24V instead of 12V system like civilian vehicles.


C-ya
 
Putting a brand new wiring harness from LMC in, I go to school for electronics so wiring and electric isn't my concern. It's staying in budget, I think getting a cucv will be worth it, they usually have no rust just hoping the tranny swap ain't a headache.
 
I have a 2wd truck, but installing an NV4500 was a breeze. I had to make a transmission crossmember, but asside from that it was not hard at all. The hardest part was making a plate for the hydraulic clutch master cylinder to fir into. It is not a bolt on cylinder but instead it is a 1/4 turn type. So don't let the transmission swap thing scare you.
 
Was your truck originally an automatic? I want to do a an NV5600 but it all depends on how everything else goes. The good thing is cucv's are stripped to the bone so everything will be brand new. I was going to do a compound setup similar to yours but the class I want to compete in only allows single trubos. I think I may just look for a k20, it will have the axles I need, I'll just change gear ratios, it'll have air conditioning, a few power options, get 1 ton 8" springs for the lift and get the mounts off of 4btswaps.com, drill a hole in the floor and hopefully have a 6 speed.
 
Yes my truck was an auto from the factory. With that being said, the floors are differant between the automatic trucks and the manual or 4x4 trucks. The transmission hump on my truck was not removable. And it was too low for the transmission to fit in the proper location. I went to the local wrecking yard and unbolted the tranny tunnel out of an 81 manual 4x4 truck. I then traced it onto my own floor (Leaving room to bolt it down) and cut the tunnel out of my truck. I then drilled the holes and bolted the hump down to my floor. Simple actually. I then had to patch the transfercase stick shift hole and cut a hole for my NV4500's stick to fit through. A couple hours later and it looks factory. I can even use a factory carpet kit, as long as I get one for a "Big hump" truck, meaning 4 wheel drive or manual transmission truck. I am not sure how much bigger then NV5600 is then my NV4500, but I would not think it to be too hard of a swap. Mine almost fell in place, with a little work I'm sure the NV5600 can achieve a factory look as well. Good luck.
 
I took the factory Chevy frame mounts and welded a "C" shaped piece of steel to them that captures the factory Dodge engine mounts that are bolted to the engine. I'll try to get a pictre today, if it stops raining.
 
Did you need a lift to fit the engine, avalanche engineering needs a 4" lift and some other guys makes them that doesn't need a lift but costs $450.
 
dekocards90 said:
Did you need a lift to fit the engine, avalanche engineering needs a 4" lift and some other guys makes them that doesn't need a lift but costs $450.
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No I did not need to lift the truck. I have a 2 wheel drive pickup so I didn't want to lift it. There was absolutely no cutting required to get the engine in the truck. I did have to graft on a manual transmission trucks tranny hump, because the stock Chevy 2wd auto trucks have a small hump. Otherwise it was a breeze. If I had run a single turbo things would be great, but since added twins, I had to flip the exhaust manifold upside down. This put the S300 too high for the stock hood to clear. That is the only real problem I have run into so far. I'll get that figured out and post my "Fix" to this hurdle.

dekocards90 said:
I forgot to ask, can the frame support the cummins in a 1/2 ton pickup?
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I went out to a guy parting out a 3/4 ton Chevy pickup of the same year and looked at the frame under it. I measured and could not find any differances between it and my own frame, other then the fact that his was a long bed and mine was a short bed. I made a few phone calls and was told by everyone that I spoke to that Chevy did not make a differant frame for the 1/2 or 3/4 trucks. The 1/2 ton and 3/4 ton long beds were identical. So there is no structural differances between them (But they never made a 3/4 ton short bed). Chevy just installed heavy duty front A arms, front and rear springs and differant differentials. So with that being said, the 1/2 ton should be able to hold the weight just as well as a 3/4 ton. I could not find any differances in frame thickness, beam height or width between my frame and the 3/4 ton asside from the the actual length of the frame. I simply swapped out 1 ton front A arms and springs and rear differential (The 1 ton spring purches are in a differant location, so I had to relocate them). I left the 1/2 ton rear springs in the truck simply because I did not want the truck to ride ike a 1 ton. I don't plan to haul too much, but I do plan on installing air springs to the rear for that "just in case" sort of thing. I guess I will find out myself, once this thing is on the road. I am currently away in the North Sea near Amstradam for work, but will be back home come the 20th of next month. I should have it on the road sometime that trip home and be able to give you my first impression. As the miles rack up, I'll see if in fact the chassis is able to handle the weight and torque of the Cummins and I'll be sure to post any problems I run into... If any, knock on wood.
 
think the frames are the same until 1 ton. Evidently the 1 tons are a little different but I can't remember the exact differences.


C-ya
 
Well I did more research and the frames are the same. It will be cheaper for me to get a dana60 and swap the front axle then buy a cucv for at the minimum 3g's. Plus I won't have to be fussing and spending more money putting in power options and air conditioning.
 
Thats good to hear. One more person verifying the facts that I had. It is a little relief, so now I'm fairly positive I won't run into any problems with my 1/2 ton frame. Like I said before, I have not really run the truck on the road much, and definatly have not put any power down for any period of time, but once I get the truck on the road and get a load on it (Or behind it) I'll be able to see how well the truck and it's frame can handle the torque of the big bad Cummins. I really have on idea what type of power I'm making, but I would like to think I shoud be able to hit the 425-450 mark and torque near 1000 foot pound would be nice. I have not been able to get any good estimates. Either my combo is fairly uncommen, or the people running it have not seen my posts to help me. Either way I'm sure I'll be more then happy with the power the Cummins wil produce. If not, more power is onlt a few bolts away. :evil
Give me a month and a half or so and I'll have a little more info for you guys. Perhaps I'll even have a dyno sheet to share. There is a reputable Diesel shop in town, with a dyno. I'll let you know how things work out.
 
I know a guy with a silver bullet whos pushin close to 600. You're compounds and your mods should def hit over 600.
 
hi, i am doing a similar swap with an 83 3/4 ton chevy. where you worried about boxing the frame. i was thinking about doing that. i wasent sure if the frame would twist while pulling or hard acceleration? also tennesse diesel conversions has a good front cross member with the cummins motor mounts.

thanks -colin
 
Well at first I was a little worried about the frame, but after compairing it to the 3/4 ton frame, it looks and measures out identical, asside form the wheel base (I have a short bed truck). So I'm not too worried about it at this point. I honestly won't be towing heavy with the truck, it is mainly for fun around town, and to tow my Nova to the drag strip, so I don't think I'll have any problems. However if I was building a sled puller I would perhaps reconsider the frames strnegth.
 
i think i am going to build this truck as a pull truck and occasional driver. so i think ill box the frame just to be safe. thanks for your input
 
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