Diesel Swap from a 454

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79ramp

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The 454 currently in my '79 C30 ramp truck is getting to be tired and smokes pretty badly. Originally my plan was to find a truck with a fresher 454 and do a swap. However, the thought has been kicking around in my head about swapping in a diesel.

My main thought here is for fuel mileage as it will be hauling my drag car and the track is about 100 miles round-trip. I will also haul a project car/truck from time to time but don't anticipate hauling more than 4k-5k on the back of it.

I do not know much about diesel but I am mechanically inclined and would like to learn. I've seen Cummins swaps and like the idea but I unfortunately do not have the proper shop set-up to do much of any fabrication so that is probably out. It looks like a 6.2 is the only real 'bolt-in' option. Would it be worth my while? And is it truly 'bolt-in'? My plan will be to get an entire truck so I have all the little odds and ends available.

Are there any other 'bolt-in' (or close to it) options?
 

HotRodPC

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Uhhhh, JMO and don't take it personal, The 6.2 is just not a good option for you. I say this due to them being gutless wonders and problematic if you have to work them hard. If you're running low 4.10 gears and freeway driving alot which sounds like you are, you'll kill it in no time. They don't like rpm. And ramp truck alone says weight, then add a race car to that too? No, you'll work that 6.2 to hard and kill it so it's not worthy IMO. The 6.2 can be Ok if it's in a truck you buy and came that way from the factory, and you just want it for a commuter truck to get 13-15mpg but you're going to drive it like Mrs Daisy and take it easy on it. More like a grocery getter.

Cummins has been done and can be done. More work to it than most realize though due to the weight of the Cummins. Not only all the normal conversion stuff and modding mounts and such, but you'll have to beef up the frame and suspension to support the weight.

I think you'd be cash ahead just to stick with your Fo Fitty Fo !!! How many miles on it? Any idea how well it's been maintained? Like would it hold it up well to a Re-Ring and bearing job, with a oil pump and timing set put in the short block and then a valve job on the heads with new guides and seals? If you have a drag car, I know you have to have some kind of engine building knowledge.

Hell, if there was any conversion I'd consider, since they're getting so cheap these days, I'd do an LS swap. A 5.3 can easily put a bit more hp/torque than your OEM tired 454 and get better mpg, and last longer as well as making your truck a bit lighter too.
 

79ramp

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Uhhhh, JMO and don't take it personal, The 6.2 is just not a good option for you. I say this due to them being gutless wonders and problematic if you have to work them hard. If you're running low 4.10 gears and freeway driving alot which sounds like you are, you'll kill it in no time. They don't like rpm. And ramp truck alone says weight, then add a race car to that too? No, you'll work that 6.2 to hard and kill it so it's not worthy IMO. The 6.2 can be Ok if it's in a truck you buy and came that way from the factory, and you just want it for a commuter truck to get 13-15mpg but you're going to drive it like Mrs Daisy and take it easy on it. More like a grocery getter.

Cummins has been done and can be done. More work to it than most realize though due to the weight of the Cummins. Not only all the normal conversion stuff and modding mounts and such, but you'll have to beef up the frame and suspension to support the weight.

I think you'd be cash ahead just to stick with your Fo Fitty Fo !!! How many miles on it? Any idea how well it's been maintained? Like would it hold it up well to a Re-Ring and bearing job, with a oil pump and timing set put in the short block and then a valve job on the heads with new guides and seals? If you have a drag car, I know you have to have some kind of engine building knowledge.

Hell, if there was any conversion I'd consider, since they're getting so cheap these days, I'd do an LS swap. A 5.3 can easily put a bit more hp/torque than your OEM tired 454 and get better mpg, and last longer as well as making your truck a bit lighter too.

Trust me, you'll have to try a lot harder for me to take something personal ;) I am just starting to kick around ideas and I do not know much about any diesels other than they take the fuel from the green nozzle and they sound like they always have a rod knock lol so any input is appreciated! :happy107:

That is good to know on the 6.2, that didn't really even come up in the little bit of web search "research" I did and I did not have much luck finding any info/opinions on doing the swap into a hauler, most of what I saw was just DD or 4x4 rigs (admittedly, I did not look exceedingly hard yet). I liked the idea of a Cummins swap from what I saw but I just don't have the metal working experience or tools/equipment to take on even the cab modification needed...let alone any frame work.

I know pretty much nothing about the 454 in my rig, the guy I bought it from got it in an estate sale and did not have much info. The one thing he was able to tell me is that the thing was used as a wrecker for a number of years so it wouldn't surprise me if there is 200k or even 300k on the clock and the motor appears to be original. As far as maintenance, it is a bit of a mixed bag of 'indicators' in terms of how well it was cared for. My first thought is if it was used as a money maker, they would probably have kept up the maintenance (in theory). However, there are some things as I've tinkered with it that make me think it was not very well kept up (for instance, the dual battery wiring was tied together by cutting the main battery cable insulation off in the middle, twisting the second cable around it, and wrapping the whole get-up in electrical tape...). So I am not sure what to think but I would hazard a guess that the short block would need more than a re-ring and new bearings.
 

Craig 85

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What about just rebuilding the 454 and then add an overdrive trans or a Gear Venders OD? Many 80's and early 90's motorhomes with the P30 chassis had 454's. Some have the Gear Venders already. I've seen motorhomes for sale out my way with 30-40K miles for as low as $1500.
 

84 M1008

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The 6.2 is gutless, bolt a Banks turbo to a J code 6.2 and you're getting about 210 hp. I had one and loved it. Add a stout 700R4 and get 4 speeds and lockup which makes it essentially a 5 speed locked up. I had that combination in my 86 M1031-K30. You have to ask yourself if the effort justifies the means .
 

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a properly set up 4bt cummins is an option, too. they can make close to 300hp and damn good torque. you can find them in bread trucks with a 4l80e behind it for around $3k. you'll get half that back in the scrap value of the aluminum alone. just be aware that in stock trim, most 4bt's are around 110-120hp, but due to their mechanical nature, they can be tuned very cheaply. they are in many 19000gvwr vehicles, so they can obviously move weight around. just aren't going to set any 1/4 mile records...

just an option to play with in your head. it's something I'd like to do with a lower miles bread truck and c10 to build a mpg commuter.
 

Blue Ox

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Having done a 6.2 Turbo (ATS, I'm not a Banks fan) swap from a 350 in a Suburban I would suggest that you need to be pretty ambitious. IF you have a diesel donor truck that has all the necessary components you might do okay. That would also depend on how much cobbing you are willing to accept.

On the plus side my 'burb got 20 MPG with a 700R4 and towed reasonably well. Well enough that when I had to tow the 7000lb race car trailer it inspired the owner to buy a diesel pickup truck. That was only in comparison to a small block, so it's not a comparable to a big block.

From a purely practical standpoint you're probably better off doing a thorough evaluation of the BB, like a compression test, leakdown test, borescope it or pull it apart and see just how worn it is and if it's reasonably rebuildable invest your efforts and $$$ in trying to improve the mileage. The math says you'll never recover the investment in fuel savings. And this is coming from a diesel guy.
 

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