I have an 83 Chevy C70 10 wheeler that we haul wood with. It has a 427 and 5/4 transmission setup. The 427 does ok, but the fuel mileage is horrible (3.5-4mpg loaded, 5-6 empty) and it needs more power. Loaded down the truck sits at about 45,000lbs. Some of the grades I pull I'm at 15-20mph (on a 55mph road) I have a 6BT Cummins I could put in, it's a VE pump out of a 92 or 93 Dodge truck. Was thinking of putting in a set of bigger injectors, adjusting the pump and twin turbo, also an exhaust brake. I'm just wondering, do I have enough engine? I can't find the specs on the 427. Horsepower and torque. I've seen anywhere from 175hp up to 300, so I don't know what is correct. I could build the 6BT for around 400hp and about 800ft/lbs without getting too carried away. That leaves the transmissions though. 65mph with the currect setup is about 4300rpm which is too high for the Cummins. I have a line on an 8v71 Detroit and mating 13 speed Road Ranger for cheap out of a 73ish KW cabover truck. Any chance that the motor would fit? I know these C70 trucks came with a 8.2L "318" Detroit. I can work on the Cummins all day, the Detroit I haven't dealt with too much, though I know they are fairly simple as well. Cummins with that 13 speed? Just looking for some advice.
I have a old C60 which is the same physical size as your truck. I'm stuck with the small block gas motor and would also love re-power to a big diesel. I haven't personally measured a 8v71, but from the dimensions Ive found online I think it is very doable. If you have a good line on one give it a shot, I would give you a hand if I was closer.
I went out to go look at the KW truck yesterday and I don't think the 8v71 would fit in mine without a bunch of work. The truck is a Cabover 1974 from what I can tell, not sure on the model. It's a non turbo motor, 318hp, 600ish? torque. Not really anything that great for it's size IMO. It was driven to that parking spot, but miles are unknown. Motor looks fairly clean, I think perhaps it was rebuilt since it's painted red? As far as I know only IH painted their Detroits red, others had that greenish color I can make the Cummins push 300hp easy and I'm much more familar with the 6BTs. The trans might be a 15 speed, not 13. It has under, direct and high on the lever and 5 gears on the shifter. I couldn't find a tag on the trans to get the model number (truck is in the weeds) or even a tag on the headliner or near the shifter (usually there is a shift pattern or something) I can get the whole truck for trade of my 427. Figure I'll use the trans and part out the rest. It has really nice 150 gal tanks, ally backboard, etc. If it was in a bit better shape I'd consider putting my dump body on it, but it's been sitting too long and would need brakes, suspension, tires, body work, glass, etc. Hasn't been used on the roads for about 20 years.
If I was dead set on an engine swap I would use the cummins 6bt.They make alot of power for a small inline engine.I have worked on a few C-70's with the 8.2 detroit and remember having to jack up the cab just to get the drivers side valve cover off .It was a tight fit and an 8-V 71 would be worse yet in that truck.Not alot of room under the front of the cab.
i have done a few swap with those 6bt's i really love those engines i had a 95 chevy 3500 with a 6bt from one of those with a ve my setup was i had a my 1/8 timing bump i bought a denny t fuel pin,POD(prince of darkness) injectors, and a hx40/35 hybrid turbo, 3200 rpm governor spring needless to say it was fun truck.first trans i had was a allison 545 never again went with a manual an nv4500 made it awesome. i also had a p-pumped early 98 dodge 3500 my second favorite i ever had that sucker had a banks twin ram intake, marine 370 injectors, home machined delivery valves, 4k gov springs,timing at 20*, hx40 turbo and 4" turbo back straight pipe with a built auto and some black 19.5's thats was a funner truck. im gonna try and find some pics of the chevy my current ford with a 7.3 has a common rail cummins sitting in the barn that needs a rebuild waiting for it. i need to start assembling every thing for that swap that will be the best one yet
Monster 76, Nice lookin trucks, can i ask you about the ford truck and trailer, what size truck and how much can you tow with that trailer, Thanks, Sam A.
The 6bt would never last under those loads and horsepower levels. In a pickup for short bursts it is OK. In a big truck with long pulls it would melt down for sure. For that size truck you need an 11 liter truck engine.
@wosama931b the truck is a 99 f350 4x4 with a 7.3,that gooseneck is a 20ft with 5ft dove tail i use it mainly to haul around a skid steer and my backhoe the skid is an 873 and my backhoe is 410e john deere not sure on the max ive been pulled over by dot and have yet to get a an over weight ticket. most of the time they just check my axle weights and they let me go @ birken vogt honestly if he watches his egts and tunes it right so its not a black smoke night mare i think it should last my buddy has an f800 ford with a 6bt its a dump truck i put the 3k gov springs i shaved the fuel plate like 4 years ago and i tuned the afc right, no smoke= no heat and its doing fine. either way i see it a stock 6bt with basics would be worlds above the 427 IMO
I guess you could be right if the engine can be gotten cheap enough, and it probably doesn't have to last all that terribly long anyway because a C70 has to be close to ageing out anyway, but it will still be a big custom project especially with the gear ratios and such, and I never really like the way those turn out. On the flip side, the 427 is a good truck engine and you can buy a lot of cheaper gas for the cost of the swap and the expensive diesel that would be replacing it, and stay out working instead of playing mechanic, then buy a truck set up the way you want it when the time comes.
your absolutely right about the practicality of the swap it is an old truck and gas parts are cheper. but some people enjoy those types of projects though and with the 6bt there is every adapter plate in the world to mate it up to any transmission the mounts are easy to make. i have bought those engines any where from 800-1800 depending on what pump miles etc.. its true the time doing swap is time its not working my strategy is i assemble all the parts before i take the truck apart to minimize down time. if it were me id do it just because i can.
Don't swap the engine swap the bed to a better truck.
I tend to agree with the above, but if you're set on a swap for whatever reasons, why not the cummins 8.3? a little better compromise between a gasser and 11liters. I don't think the 5.9 is going to get you much over the gas.
No it wouldn't melt down.
The 427 isn't staying in the truck, I'm not happy with it. Unless I can double the power and fuel mileage for under $2000 the 6BT Cummins makes more sense. I did pull the smog junk off it yesterday as well as modified the air breather to flow more air. Might help a little, didn't figure it would hurt. Not sure why it even had an A.I.R. pump since it never had catalytic converters. Truck has 8900 miles on it, it's hardly worn out. Was used by a lumber mill in Fairbanks to move sawdust to a boiler plant a few miles away. Sure it needed a bit of work here and there, but it's pretty much been all gone through by me. Just finished going through all the brakes yesterday, had to rebuild one wheel cylinder that was hanging up a bit, cost me $9 total for a rebuild kit, some brake cleaner, and RTV for teh axle shafts. I am a mechanic, went to school and have worked on and off on heavy equipment and light trucks for years. I will do the engine swap this winter when I'm not cutting wood. No down time. Also going to paint the cab too. The 427 is in great shape, but it's a gas hog and it's gutless. Loaded down I'm pulling grades at 15-20mph and it takes miles to get up to speed on the flats even. I've been getting 3.5-4mpg loaded and 5-6 unloaded. I don't expect to have a racecar, but my friend has a similar truck with the 8.2L Detroit and it's way better. That motor only makes 230hp, 468ft/lbs... basically what a stock 6BT makes. He also has a Ford 9000 with the 8.3L and that gets 6-7mpg sitting at 75,000lbs. I would consider the 8.3L but they are expensive (have seen them running as "cheap" as $4-5000) and I don't think it will fit. I picked up the 5.9L for cheap. The parts for the 427 are hard to get. The parts other BBCs use aren't bad, but it's the 427 specific stuff. Molded hoses, some gaskets. I've had to either "guess" using another BBC engine or special order it in. About the only thing the parts stores carry are the oil filter and fuel filter which I'd bet many other models use as well. Diesel is cheaper than gas. Not to mention the Cummins will be better on fuel too. There is no advantage to keeping the gas engine. Everything else I own runs on diesel other than a few chainsaws and a small splitter we hardly use anymore. Last time I had my tanks a couple weeks ago I paid $3.98/gal for gas, and $3.80/gal for diesel.
I have about $5000 total into this truck including the Cummins. I've been keeping my eyes open for 3 years and haven't found a better deal. In a few years after my company grows a bit I do plan on upgrading to a bigger truck, but for right now I don't have a spare 30-40k laying around.
I don't know how to make pictures go on this site, but I have photos of the truck on Facebook https://www.facebook.com/ValleyFirewoodAK
The red Dodge in my facebook photos is a VP44 Cummins and it makes 522hp to the rear wheels. Has almost 300,000 miles on it... hasn't "melted down"
Its pretty hard to get power out of the tall deck BBC's without lots of $. The only stock power #'s I could find were 260/420 but that was late 60's so I'm guessing 80's would be much lower. I say do the cummins, even if that 427 makes 400 lb/ft the Cummins will do the same stock with double the mileage. If you kept it around 300hp with good air it'd pull as hard as you want all day long with no gauge babysitting. Sent from my DROID RAZR HD using Tapatalk 4
The C-70 looks to be in good shape ValleyFirewood,alot of life left in it.Good luck with the engine swap.I think you will notice a big difference in power with a stock cummins 6bt over the 427 without cranking up the fuel.It will take some time wrenching & fabricating but will be worth it in the long run .Even better that you allready have the cummins 6bt in hand. Interesting operation you have with the firewood processing.
Blue Bird puts the 6BT in full size 66 passenger buses that log 200,000+ miles, I can't understand why it wouldn't work in you Chevy. It certainly ought to have at least the longevity the gas engine does. The connecting rods and bearings are huge in that thing, I seriously doubt it will be a time bomb.
Been busier than all heck. I have 2 guys working with me, I put in 90-100 hrs a week as well as one other guy and the 3rd guy is semi-part time (works when he "can"... let's just leave it at that). Looking to hire if anyone is in the Wasilla/Palmer area and can work from 8AM-10ish PM 6 days a week. Started the company last year, just part time since I had a full time job in the Air Force. I had bought a log truck load of wood for my house and was cutting it at a friend's horse farm. I only needed 5-6 cords out of the load so I put an ad up for the remainder, figured I could make some of the cost back. Well that load led to another, to another, to another. Well ended up selling about 100 cords, cut, split, and delivered all by myself, all with a Stihl MS290 and a small (5hp) splitter that had something like a 25 second cycle time. Started off this year cutting by hand, but upgraded the saws to a 460 and 660 and a 12hp splitter with a 16gpm pump. I was still working fulling time but one my way out the door. Medically separated in March and used my severance $$ plus a loan to buy a processor, PPE, skid steer, dump truck, etc. I can do 5-6 cords a day with this setup which isn't too bad. My old setup with 3 guys we were doing maybe 2 cords a day and I'd get home worn out and barely able to walk. I got the transmission models, can anyone help me on the ratios? I will need to change something because 65mph is about 4300rpm, which will be too high for the Cummins. I can't find any specs online. Main trans is a Spicer CM-5052-C Aux trans is a Spicer 7041 Both are O/D transmissions according to the paperwork I have from the truck, but I can't figure out the ratio. I have no idea what the axle ratio would be. They are Eaton axles but hard to find parts for... no one has hard of them in the last 30 years pretty much.
I find this curious because in my experience, an identical 427 truck would pass up a truck with an 8.2 Detroit (barely). What I am saying is that the 427 ought to have more power than the 8.2. Maybe something is wrong with the 427?
We had 7 pumper- tankers (1000 gallons) and 1 tanker-pumper (2000 gallons) that were all 1982 C-70s w/ 427s, and they would leave nearby depts. diesel pumpers. Those 427s weren't gutless at all.
I have an 87 C70 with the 8.2 and deem that gutless as well. I would put the Cummins ahead of any gassed, the 8.2 and a 3208 Cat. The DT 360 or 466 IH engines would be about the only thing better than the 5.9 Cummins in my opinion. Good luck, I think you are on the right track. There is info about both trannys on the stovebolt forum. The truck must be fun to drive with the brownie in it. I would jack up the rear and count drive shaft revolutions to get your ratio and maybe source a better ratio rear out of an old school bus or something similar. My truck does 62mph on the governor for a reference. I'd have to research what ratios I have as well.
if you got the time and the know how to swap a motor. I would choose the 8v71. a 8v71n/a I think has around 900 to 1000/lbs of torque with n65 injectors (most common). but It might not fit without doing a lot of work. I know you could get the 8.2 in 83 but thats a totally diffrent motor. A 8.2 is about 500 or 501 ci and a 8v71 is 568. I've drove both and the 8v71 has twice the power as the 8.2 but the 8.2 gets better mpg. just get some good ear plugs if you choose the 8v71. and I would keep the 5/4 set up the 8v71 has sort of a narrow power band. plus the 8v71 would last longer than 5.9.:bash
8v71 is about 318hp, 800 ft/lbs. with an RPM limit of usually 2100. 2100 RPM in high gear is around 40mph. The motor I have is in a 1973 KW tractor and as far as I know is the stock motor. Odometer on the truck is not there so who knows what it has for miles. I know the truck spent 20+ years running the ALCAN. I'm not saying it's a bad motor, just that one isn't a great one. Not to mention that motor weighs well over 2000lbs, while the Cummins is about 1000. That means 1000lbs more I can haul. I pulled all the smog crap off a few weeks ago and also modified the air cleaner for more air flow. Didn't really seem to make a different, but I've just done local delivers so far. Going to bypass the governor, I'm thinking it may not be allowing WOT when it's needed (like pulling hills)
interesting.....
Im more shocked by the fact your putting 45,000 lbs on a 40 year old 2 axle truck!
Can you get or could you ever get a 10wheeler with a cummins 6bt in it? I would like to know how good it would work.
He actually has a C-70 tandem, Dualie
thats an ultra rare beast
Sure is around here, I've seen a few government ones. I guess it makes a low bid tandem.
They are very popular around were. If you had the money thats what you would buy. I dont remember seeing any thing other than GM c70 twin screws hauling rock and spreading lime between the late 60s to the end of the 80s. After that diesels trucks were starting to be used and most GM dealer ships closed. Its harvest time here and their are several farmers that have them. Alot of the biger older farms have them that they bought new in the 70s and 80s. Most have lead a easy life and are well cared for looking like new.
Maybe I mentioned the other truck that my friend has? Load 10-12k on that. 1972ish C50. Actually he has 2 of them. One with a 350, the other with a 305 V6. My truck is 30 yrs old and is 3 axle.
I had a 1968 C50 with a 302 straight 6 gas engine. No powerhouse, but got mileage well up in the teens pulling a 16,000 lb trailer. It would run 62 with an empty trailer, and barely get over 50 with a load. It was a retired state hwy dept truck.
Did you put the 302 Jimmy in it? The only time i ever saw one it was in a army 6x6. If it got that good of mileage it was alot better than the 292 straight 6. I have had several one was in a 1970 chevy 4X4 it got about 9.
Nope, I guess the hwy dept ordered it that way, or maybe they pulled it out of something they had laying around. The man I got it from got it from a dealer who he thought got it from the state auction. The SC Highway dept had a bunch of military surplus stuff around, maybe that's where it came from. It had a 5 spd and a fairly high rear end.
If it was from a military truck all the ones GMC 302s with 5 speeds were overdrives. Maybe yours was a overdrive.
Correct me if I'm wrong, but I always was of the understanding that the 427 Chev was designed as a performance motor, (as in muscle car), not a puller. If it were me, I would look seriously at a 6V53 Detroit, (6V53T if you can fit it) and a RT6613 Roadranger. The 6V53 will handle 45,000lbs on its ear and if you really wanted something special you could fit a Jake Brake, which would help you in descending the hill you just climbed. The 6V53 will be a fairly easy fitment too. Detroits are probably the sexiest sounding engines ever and would compliment your truck well. 6V53's regularly served in International Loadstars and Dodges at well over 45,000lbs.
Could we have a update on this thread I have turn down a 2001 Fl70 8.3 and six speed with ex brake for 3000$.
The 427 came in two versions. One being a performance engine and the other a truck engine . Both engines shared a lot of similarities. The truck engine had a taller block deck to allow for an extra compression ring on the piston. Bigger water pump, also had an extra bell housing bolt at the top.
For about all of 10 minutes LOL!!! I drove 53 and 71 series Detroits on a daily basis and while I have a bit of nostalgia for their song, I remember how beat up I was at the end of the day from it. They were LOUD no matter how much muffler you put on them. The 92 series was the first that was tolerable.
Old Chevys and Jimmys . That's what I'm used to . This is my personal opinion and we all know what that's worth .If you stay with a gasser , take the time to swap that big block with an LSX out of a late model truck . Works wonderful with all the electronics but a carb can be used . It not the easiest to do but if you find one with a 100,000 at the salvage yard it's doable and you will still have 200,000 left in it and probably twice the fuel mileage , twice the Horse power and torque . Ideally you would use a large frame diesel But the biggest turd in the punch bowel is the rear gears . Most those old gassers had a rear gear somewhere down in the 6:50 range WAAAAY to deep for a proper diesel set up
I haven't really decided where I'm going with the truck. If I put the Cummins in with the current drivetrain I'd be topped out at maybe 50mph.
That's the beauty of the 6V53, 3208 CAT, 555 Cummins and to a lesser extent the 903 Cummins. They were all designed in an era where petrol V8's were being replaced by diesels and they have rev ranges comparable with the petrols. The 6V53 is in many ways the pick of the bunch as it has really good torque figures, loves revs and can be fitted with a Jake Brake. The Cummins would be second, (particularly in VT trim) and the Cat would be third due to not being jake compatible. Assuming a tire height of around 41" and a rear axle ratio of around 6.5:1 you would need around 3300RPM to see 65MPH. Just remember that powering the truck at 65MPH is easy. Slowing it down can be a whole different story. Double the speed and quadruple the stopping effort required, so even the jump from 50 to 65MPH means a lot more anchor is going to be needed to stop your rocket sled.
make sure the vacuum avance is working properly in the distributer of that 427.
No vac advance on it, just mechanical.
Gotten anywhere on this?
Here im still running my chev 70 with a 427 and 5&4. Gas right now is cheaper than diesel at 1.14 per litre and diesel at 1.38 per litre.
Dunno what that is in American, but here gas is $3.85 and diesel is $3.65
Gas has gone down here 2.89. I dont often look at the price. I have to have it to make money. One good thing the last 3 vans i bought to junk had almost full tanks. That helps out alot because i have to pay alot for junk vehicals because so many guys are junking around here. I gave 300.00 apeice for them and got 50.00 plus worth of gas out of each.
stiil looking? what is your status on the truck? I can give you some real world on 366/427 in C60 and C70. (also some real world on 5.9L, 7.3L, and Detroits - plus the bigger offerings, if you want)