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6.2 or 6.5 diesel versus 350 V8Tbi. Out of which diesel engine is better than the 350?

black dawg said:
What kind of mpg do you get now?
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black dawg said:
What kind of mpg do you get now?
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Dont know exactly but lets put it this way:

Lets say the suburban is on empty and i put 20 dollars in to get from new orleans to slidell and back which the minute commute to new orleans to slidell(or further like almost to gulfport mississppi)is 39 minutes away. I can come back on the same tank depending on which fuel i use such as unleaded or unleaded premium the way gas prices are now
 
blackandgold51 said:
Dont know exactly but lets put it this way:

Lets say the suburban is on empty and i put 20 dollars in to get from new orleans to slidell and back which the minute commute to new orleans to slidell(or further like almost to gulfport mississppi)is 39 minutes away. I can come back on the same tank depending on which fuel i use such as unleaded or unleaded premium the way gas prices are now
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Numbers. We need numbers. Starting with a full tank, drive for a while, then fill up. Record how many gallons you bought and how many miles you drove. Divide the two and we'll start from that.
 
campfire said:
Numbers. We need numbers. Starting with a full tank, drive for a while, then fill up. Record how many gallons you bought and how many miles you drove. Divide the two and we'll start from that.
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Come to think of it,i might do what you said about a diesel co conversion: get a truck with a 6.2 or luckly a 6.5 with a turbo for am easy switch conversion.

Also to think of it with like you said with a diesel having less tune up to deal with along with me driving mph below the speed limit with my suburban having a 700r4 transmission, and with diesel being low here(2.09 bucks agallon is the lowest i sqw so far) i might make out ok
 
Remember if you use a 6.5 turbo in a square the turbo and the AC stuff take the same space. One must be removed
 
blackandgold51 said:
Come to think of it,i might do what you said about a diesel co conversion: get a truck with a 6.2 or luckly a 6.5 with a turbo for am easy switch conversion.

Also to think of it with like you said with a diesel having less tune up to deal with along with me driving mph below the speed limit with my suburban having a 700r4 transmission, and with diesel being low here(2.09 bucks agallon is the lowest i sqw so far) i might make out ok
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May as well just buy a diesel truck and skip the conversion entirely. At least get some miles on one before you pull the plug on your 350. Also keep in mind that the 6.5 turbine setup interferes with the A/C setup on these rigs. If you have A/C, you'll hafta do one of a few aftermarket mods to make a 6.5 fit. 6.2 or 6.5 without the turbine doesn't have this problem.
 
campfire said:
At least get some miles on one before you pull the plug on your 350.
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What you mean by that? I like to keep the one have for a while longer plus already recently had it painted along with other mods: led light bar, "flat" classic running boards, black gloss painted rims and others etc.

I might want to put a 6.5 and i dont much carefor ac.
 
blackandgold51 said:
What you mean by that? I like to keep the one have for a while longer plus already recently had it painted along with other mods: led light bar, "flat" classic running boards, black gloss painted rims and others etc.

I might want to put a 6.5 and i dont much carefor ac.
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If you do decide to do an engine swap, do some test driving before you tear out your nice 350. The last thing you wanna do is put in all the work to do an engine swap and then decide that you don't like the end product.

If you're up for the slightly-more-cramped engine compartment, I would take the 6.5 over the 6.2. 10 extra years' worth of engineering experience on the newer engines. By the time that the 6.5s went out of production, a whole bunch of positive changes had been made from the original 1982 6.2 design.
 
campfire said:
If you do decide to do an engine swap, do some test driving before you tear out your nice 350. The last thing you wanna do is put in all the work to do an engine swap and then decide that you don't like the end product.

If you're up for the slightly-more-cramped engine compartment, I would take the 6.5 over the 6.2. 10 extra years' worth of engineering experience on the newer engines. By the time that the 6.5s went out of production, a whole bunch of positive changes had been made from the original 1982 6.2 design.
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Gotcha. Which best year 6.5 i should get? By the way i want to show some pictures of the suburban i have. How i post pictures?
 
blackandgold51 said:
Gotcha. Which best year 6.5 i should get? By the way i want to show some pictures of the suburban i have. How i post pictures?
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Depends on what parameters you're looking for. The 1992-1993 engines are mechanically controlled, so a tiny bit simpler to install. Starting in 1997 GM switched to dual thermostats and a higher flow water pump. This helps avoid overheating issues that were common when 6.5 engines were worked hard.

Serpentine belts should be on anything newer than 1987ish. Either engine from a newer-series truck ('88 for the pickups and '92 for the Suburbans) should be set up for an electric fuel pump like your EFI 350. Square-body engines used mechanical pumps on the block. At a few points, engine block designs were tweaked, but I don't know which years are which. Except for the first year (1982) 6.2 engines, they had a higher-strength block that is painted red. When GM discontinued the 6.5s, AM General bought the tooling and continued producing them for military rigs (like the HMMWV). These engines are probably the best of the bunch.

Here is some good reading if you want more info.

http://www.gmc4x4.com/topic/1809-gmdetroit-6265-turbo-diesel-performance-toolbox/
http://www.dieselplace.com/forum/63...sel-engine/391426-6-5-newbies-start-here.html
 
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If my focus were mpg, I would use an early 6.2 (the ones that the injectors point more out, and not up) they seem to get the best mpg. And I would skip the turbo.

but first get a mpg figure from what you have now.
 
black dawg said:
If my focus were mpg, I would use an early 6.2 (the ones that the injectors point more out, and not up) they seem to get the best mpg. And I would skip the turbo.

but first get a mpg figure from what you have now.
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This. And install new injectors with it. Old injectors aren't going to mist the fuel as well, which hurts power and mileage both (but does cause lots of black smoke out the back :rolleyes:)
 
I've got a 2000 3500hd 6.5/nv4500/Dana 80 w 4.63's
I'll gladly trade someone for a like condition 454 or 8.1 setup.

Come drive the truck before I pull it.
I'll trade everything needed.
Complete motor, accessories, wiring ect.
 
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