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Old 04-14-2012, 11:15 PM   #1
Car'n'Guitars
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6.2 Diesel vs SBC

Okay what are the advantages and disadvantages of each with stock set ups? Such as towing capabilities and fuel mileage?
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Old 04-14-2012, 11:21 PM   #2
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Re: 6.2 Diesel vs SBC

The 6.2L will get better mileage and they have more low end torque. If you keep the oil changed and the fuel filters changed, they will go forever. Another advantage with the diesel trucks, is they come with hydroboost which gives you more stopping power. IIRC only the one ton gasoline trucks come with hydroboost.
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Old 04-14-2012, 11:23 PM   #3
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Re: 6.2 Diesel vs SBC

Will the 6.2 have the torque capabilities though?
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Old 04-14-2012, 11:32 PM   #4
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Re: 6.2 Diesel vs SBC

You can build them to be respectable. My diesel burb is my tow rig and I have no complaints, I love it. I can't build it up like the guys with the cummins or the duramax's build up their engines, but it was never meant to be an 800hp powerhouse.
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Old 04-15-2012, 12:11 AM   #5
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Re: 6.2 Diesel vs SBC

i've done alot of thinking (bad sign right there....) about this subject:



Quote:
Originally Posted by Car'n'Guitars View Post
Will the 6.2 have the torque capabilities though?
1) The thing about the 6.2 is you can run a lower gear---like 3.73 and still get 20 or more mpg. If you do that with a gasser then the mpg goes out the window. Of course with 4sp OD transmissions, it's not really an issue anymore.



2) To me, the advantages and disadvantages of both are as follows:

Diesel has the advantage of really good mpg but may have a high(er) initial cost plus i'm unfamiliar with the setup; A new 6.5 will cost about $8000 and does not include the injectors or pump. How much do those cost?

A new 350 might cost $1500-2000. But the mpg is nowhere near as good.


So i think it boils down to how much driving you are doing. The gasser may cost .25 cents per mile in gas, while a diesel might cost .13 cents per mile.

i think in terms of total cashflow, the gas is a better move in most cases.

3) As far as which do i prefer, the 305 or 6.2, it would depend on what the intended usage would be.
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Old 04-14-2012, 11:37 PM   #6
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Re: 6.2 Diesel vs SBC

What kind of fuel mileage do you get?
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Old 04-14-2012, 11:43 PM   #7
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Re: 6.2 Diesel vs SBC

My speedo is off because I'm running 35" tires, but my guess is unloaded I'm getting around 20 and with a heavy loaded trailer...probably around 18. I think I could get a little better mileage if I change gears in the axles but I don't tow that often so in the long run I don't think it would be worth it. My Burb has 4.10 gear right now and I think it would perform a little better if I had 4.56's.
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Old 04-14-2012, 11:45 PM   #8
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Re: 6.2 Diesel vs SBC

Okay so 6.2 vs a 305 which would you prefer?
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Old 04-15-2012, 12:15 AM   #9
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Re: 6.2 Diesel vs SBC

I would be doing a lot of driving with it and pulling/ hauling. But I can get a 6.2 diesel for $300.
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Old 04-15-2012, 12:46 AM   #10
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Re: 6.2 Diesel vs SBC

If towing an hauling, then i would definitely prefer the diesel over a 305.


It's good that you can get one for $300, but how long will it take to install? Realistically? Could the time be better spent earning money?

To me, it's all about cashflow, not just mpg.


For instance, my first engine swap/head gasket replacement took 3 weeks which i took off, which is about $3000 missed income. Of course, the learning experience was priceless, but strictly numbers-wise on paper it was not a good move.
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Old 04-15-2012, 12:58 AM   #11
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Re: 6.2 Diesel vs SBC

Where I am and with the people I know, if I wanted to do a swap it could be done in a day or two.
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Old 04-15-2012, 02:08 AM   #12
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Re: 6.2 Diesel vs SBC

If they can really switch it that fast, then more power to you.

But, we are talking:

1) i think you need 2 batteries? So you need another battery tray?

2) Is the exhaust exactly the same? Will it just bolt up to the small block exhaust. i've never gotten a clear answer.

3) What about brakes? i think you have to go with hydroboost. i don't even know what that is.

4) Will the torque converter be compatable and will the trans shift the same way ( i don't think diesels don't produce vacuum in the same way as a gasser?)

5) Then you need glow plugs. They need to be wired in.

6) Can we use the same gas tank, and if so what about the lines?

7) Proabably a zillion other things which i don't know about.

It is because of these reasons is why i will probably stick with gas. Plus i just like the small block.
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Old 04-16-2012, 01:34 PM   #13
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Re: 6.2 Diesel vs SBC

Quote:
Originally Posted by Car'n'Guitars View Post
Where I am and with the people I know, if I wanted to do a swap it could be done in a day or two.
Have you thought about putting in a Cummins 5.9 6BT? Maybe not quite as good fuel economy solo but much more power and better reliability. There are also tons of these engines floating around due to the engine outliving the Dodge truck.
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Old 04-16-2012, 03:59 PM   #14
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Re: 6.2 Diesel vs SBC

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Have you thought about putting in a Cummins 5.9 6BT? Maybe not quite as good fuel economy solo but much more power and better reliability. There are also tons of these engines floating around due to the engine outliving the Dodge truck.
Oh yeah that's what I really want just can't afford it though.
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Old 04-16-2012, 04:24 PM   #15
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Re: 6.2 Diesel vs SBC

almost every gas station has it now, but sometimes ,diesel can be hard to find
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Old 04-15-2012, 02:09 AM   #16
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Re: 6.2 Diesel vs SBC

From what i have seen a diesel is better for towing because of its torque and you won't have a huge drop in your mileage like a gas engine will towing.The swap could be easy but does it have a trans or you going to use what you have?I wouldn't use anything less then a turbo 400 with it.Do some searching on here you might find someone that swapped one.
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Old 04-15-2012, 02:23 AM   #17
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Re: 6.2 Diesel vs SBC

Yes everything would need to be converted. And if I do decide I want to do it then every aspect of it will be researched, and the truck right now has a th700r4 in it.
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Old 04-16-2012, 07:35 PM   #18
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Re: 6.2 Diesel vs SBC

Quote:
Originally Posted by Car'n'Guitars View Post
Yes everything would need to be converted. And if I do decide I want to do it then every aspect of it will be researched, and the truck right now has a th700r4 in it.

So....."they" really can't switch it over in "a day or two?"


That was mah point; Don't just look at mpg figures. Look at the total cost of going diesel and how long it will take for it to pay itself back. i think you'll find in most cases gas is the better route.
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Old 04-17-2012, 03:46 PM   #19
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Re: 6.2 Diesel vs SBC

Quote:
Originally Posted by C-10 simplex View Post
So....."they" really can't switch it over in "a day or two?"


That was mah point; Don't just look at mpg figures. Look at the total cost of going diesel and how long it will take for it to pay itself back. i think you'll find in most cases gas is the better route.
I agree with that to a point.

I only like the diesels if they are turbo charged, otherwise I have no interest.

If you are going to spend the money, why not make what you have more efficient? Or go with a more efficient gas swap?

Don't get me wrong, I like the diesel swaps if it's a turbo, I'm just not liking the diesel gas prices at 30-40 cents more per gallon when you consider you are paying more for a fuel that is unrefined, doesn't make sense. But the fun you can have with simple tuning on a turbo diesel makes it worthwhile

Personally I went with a LS 6.0 swap and a 4L60E behind it for my blazer, and I'm getting 22 mpg with this setup, and it has more usable pulling power than a gen 1 sbc or any non turbo 6.2 diesel. There is good gas mileage to be had with gas powered engines if you science out the entire setup.

I was in the same dilema with my 79 1 ton pickup. The 454 spun a bearing. I would have loved a turbo diesel swap in this, but the time and effort and money was holding me back. I instead dropped a GM 502 crate engine down in it (cheaper and easier). It has all the power I need (dyno'd 537 ft lbs.) and gets 14 mpg driving easy. Granted whether towing or not I don't get the mileage a turbo diesel truck does however, but it's not bad for a big inch engine in a truck shaped like a brick. Considering it makes the same power the GM duramax did circa 02-03 (a few years ago now) makes it a pretty fun truck to drive.

What I'm getting at is, I don't think you are weighing all your options that are available to you
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Old 04-15-2012, 02:30 AM   #20
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Re: 6.2 Diesel vs SBC

I'm a big 6.2 fan
I prefer them over a stock small block.
I have a 82 K20 Burb with a 6.2 and 700R4.
It does great in the power department.
I haven't towed anything with it yet.
You will need a diesel specific torque converter.
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Old 04-15-2012, 02:43 AM   #21
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Re: 6.2 Diesel vs SBC

Remember it may get better mileage, but diesel is also more expensive than gas....

I want to convert my truck to run on propane. Right now locally it's $2.79/gallon for propane, $4.05 for gas, and $4.39 for diesel.
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Old 04-15-2012, 02:49 AM   #22
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Re: 6.2 Diesel vs SBC

If you can pull off a cheap diesel swap, do it! I love having a diesel. It's the best of both worlds because you can have a 30+ year old truck and get the same MPG that brand new trucks are getting.

Vacuum for the tranny comes from a mechanical diaphragm pump on the engine that is in the location a distributor normally would be.
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Old 04-15-2012, 10:36 AM   #23
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Re: 6.2 Diesel vs SBC

you will need to either clean the gas tank really good or get another tank. also,diesel fuel makes rubber soft so you may have to get some 2 wire hydraulic line to use as a supply line. as far as a 305, the gas mileage on them aren't that great. if you're gonna use a small block,a good stock 350 with a four barrel is better. fuel mileage on anything is determined by how far you stick your foot to it. by the way, the pumps for the 6.5s are around $1200,a 6.2 probrably ain't much cheeper and most injectors carry a core charge up to as much as $300 each or more.
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Old 04-15-2012, 10:41 AM   #24
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Re: 6.2 Diesel vs SBC

Yeah I am aware of prices and all that good stuff. I guess I will do more research before I do anything. I'm not in a big hurry to do it.
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Old 04-15-2012, 10:49 AM   #25
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Re: 6.2 Diesel vs SBC

Pretty sure these trucks had a higher tow rating with a 350/4bbl than the diesel option. The diesels were geared almost strictly for economy. They weren't really a powerhouse of any kind. I'd stick with a solid 350 and call it a day. If you want a diesel, I'd search for a diesel truck so everything is correct. If you can swing it, it would be the best of both worlds to have one of each!
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