best diesel conversion

[james93711]

i'm looking to go diesel in my 86 k5. i really like what people are doing with these cummins but its expensive as hell. i would like to keep it as cheap as possible and not have to improvise on things. its got a 350 carbed 700r4. ive read that the 6.2 are junk but cant believe what everyone says because maybe they just got one thats been trashed or trashed it themselves. i've always been easy on my cars and ive always maintain them, i hear of people putting 300k on their 6.2 with no probs and still running like a champ. just looking for some options. thanks

 

[crawlink5]

best and cheap don't really go together. Diesel and cheap don't go together.

A 6.2 which is probably the cheapest way to go and you can get parts.

I see you are from California. What will the inspection nazis allow on your vehicle?

BTW - I like my Cummins 4BT

 

[Big Ray]

I have a 90 'burban, it has a 6.2 with 278k miles. Having said that, my choice would be a cummins. Look into a 4bt maybe? Lots of vids on youtube with them.

I'm thinking a 6bt when mine dies down the road. Just cuz it's a burb & needs the extra umph.

 

[james93711]

california is a pita for gassers, im working on getting my k5 gasser smogged at the moment. hoping i dont need a new catastrophic contorter.. usually seafoam can clean those out pretty good though. i dont think there are any inspections for diesel here though.

i'm kinda thinking the 6.2L since the bt4 are about 3k average. its not in the best shape and i might end up selling it to move to nebraska in a few months, so i might end up getting a cucv after that. i hear alot of bad things about the 6.2 and alot of people swear they are rock solid.

 

[K5-CJ5]

There are many misconceptions about the 6.2/6.5 engines. Are they power houses...No, are they an industrial diesel like a Cummins....No Do they get fantastic fuel economy....Yes, do they make enough power for a K5...Yes (much better with a Turbo)...Diesels in general are more expensive to repair than gas, however, long term you do recoup that upfront expense because repair intervals are farther apart. A 6.2/6.5 will be a fairly easy swap as it will bolt directly to your existing transmission with no modifications, it uses the same motor mounts as well.

They can be built to be rock solid, but it costs $$$. If you want a 6.2 you need to look for a high nickel red block which as I recall was late 81 early 82 production. If I were you I would look at a 91-94 (pre electronic injection pump) 6.5 and do a turbo. If your k5 has a/c then a 6.5 turbo out of a truck will not fit without airbox modification, if its a non a/c truck it will fit no problem. As far as cali smog, its no prob. You go down to a referee station, get it stamped as a diesel and never worry about smog again, although cali will raise your reg. cost because its a diesel....gol figure that one out!!! when I did mine it wasn't excessive. If you want a powerhouse diesel, then Cummins is the only way to go, while you can make the 6.2/6.5 have power, it would cost more than throwing in a 12v and modifying the injector pump.

 

[james93711]

i think a 6.2L would work great for me, im not towing anything except maybe my jet skis, prob gonna build a tear drop camper, nothing much over 1000lbs. just want enough power for moderate off roading. i seen these isuzu 4bdt that seem like a good swap too. but i would like to keep it simple and just drop it in. what all would i need, is the pump an in tank fuel pump? would my 700r4 be good if i dont drop my foot and spill the trans all over the road? i know a bit about my gasser but i know nothing at all about diesels.

 

[Stomis]

Dont do the isuzu swap. You'll be into it for as much as a 4bt swap.

Honestly I would recommend a mechanical 6.5TD or a 6.2 with a banks kit on it.

 

[K5-CJ5]

An early 90's 6.5 block would be the strongest casting. You need a water/fuel separator, the fuel pump is mechanical on the block and feeds the injector pump, no intank pump needed. the 6.2/6.5 came with a 700r4 in many applications although the shift points for a diesel and gasser are slightly different, although I have heard of people running a gasser trans with a diesel with no ill problems. If you go the turbo route you will need to modify exhaust slightly if you go N/A you wont need to modify exhaust as I recall.

 

[K5-CJ5]

A turbo is really good idea, not required but youll be much happier with one.

 

[2INSANE]

I have a 83 GMC 3/4 ton truck 6.2 N/A Diesel and 1984 m1009 k5 6.2 n/a diesel.

Both original motor and both still running strong like new.

Pros:
Could put a turbo on for more power
Reliability
Good torque
Good MPG
No Emissions
Easy to work on
Parts easy to get
Parts are cheap
I once had my Altinator go out on top of Farmington peak, loosing all power, lights etc, but the motor still ran and purred like a kitten because they run off heat and compression. Not spark.

Cons:
N/A Gutless!
Diesel prices are higher then gas
For some reason, the injector, driver side closest to firewall, tends to leak fuel at least once a year. Usually because the rubber cap on the nipple falls apart from the diesel eating it.

If you can afford a Cummings motor and the maintenance/parts when it breaks down, do it! If not, keep with the 6.2 and throw a banks or 6.5 turbo on it.

 

[crawlink5]

What are the hp and tq numbers on the 6.2?

On the various diesels also keep in mind that they are sometimes much heavier. the 4bt 4 cylinder is about the same weight as a big block chevy. I upgraded to big block springs and a d60.

Diesels have more torque at idle so when you are taking off there from a stop the engine is wanting to move the weight of the truck regardless of the heavy truck wanting to sit still. So think of everything between the engine flywheel and the rear tires as possible weak points.

The 4bt is a VERY tall engine. Had to lift the blazer to get it to fit. It is about 1/2" from hood and now about 4" from front diff. Had to do this during swap.

The 700r4 will not hold up behind a 4bt. So I upgraded to a NV4500 during swap and went to a NP205 even though the 203 would have been fine. For a diesel with torque think TH400 or up or 265 or up.

The 6 cyl cummins is stupid heavy so be prepared if you go that route. But can be had for a good bit cheaper than a 4bt.

Cost of an engine in a major engine swap can be just a portion of the cost due to upgrading trans, xfer, rear diff, springs, a/c compressor and lines, starter, alt, etc. unless this stuff will fit your new engine. I changed during swap to a d60 front (wanted one anyway) rather than have more weight and torque on a d44 front.

Diesel fuel tanks are different from a gas as they are not galvanized. The diesel will leach out into the diesel and then plate out into the high pressure injector pump. I changed mine during swap.

 

[K5-CJ5]

The 6.2/6.5 came from the factory in blazers, so the springs, axles, tranny etc are not an issue with a swap of the 6.2/6.5. They are a tad heavier than a 350 but not by a whole lot, of course they do no put out the numbers of the cummins...The numbers depend on what year and model the engine is but about 190 HP @ 3400 RPM and 380 fl/lbs @ 1700.

 

[Hogback Fabrication]

The 6.2/6.5 came from the factory in blazers, so the springs, axles, tranny etc are not an issue with a swap of the 6.2/6.5. They are a tad heavier than a 350 but not by a whole lot, of course they do no put out the numbers of the cummins...The numbers depend on what year and model the engine is but about 190 HP @ 3400 RPM and 380 fl/lbs @ 1700.

6.2's had 135-165 hp and 240-330 ft lbs., AFAIK most civilian trucks go the lower power 6.2's and the CUCV trucks and maybe the 1 tons (?) got the more powerful 6.2.

Everyone mentions the turbo kit as an option, for $2500 I'd invest that money into a motor made by Cummins

 

[K5-CJ5]

6.2's had 135-165 hp and 240-330 ft lbs., AFAIK most civilian trucks go the lower power 6.2's and the CUCV trucks and maybe the 1 tons (?) got the more powerful 6.2.

Everyone mentions the turbo kit as an option, for $2500 I'd invest that money into a motor made by Cummins

My numbers were for a 6.5 from early 90's, sorry! Its not 2500 to go turbo either, I mean yes brand new from banks but not if you get a 6.5TD engine. I usually see used turbos such as the sidewinders for 800 used.

But I agree the Cummins is a much much better power plant, although the cost of the swap is more expensive and more difficult for the OP uses.

 

[Hogback Fabrication]

But I agree the Cummins is a much much better power plant, although the cost of the swap is more expensive and more difficult for the OP uses.

I agree that the Cummins swap is going to end up costing a good deal (trust me, I know! ) but if it's out of the question then so is the Banks turbo kit.

I forgot about swapping 6.5 parts onto a 6.2, of course finding a takeout J-code (I think that's right) diesel from a military truck might be a good way to go (as so many of those get swapped out).

 

[K5-CJ5]

my 6.2 with 6.5 turbo made good power, got great mileage, I could literally wheel an entire day with my 6.2TD on a few gallons of diesel. That being said Im going to switch my current K5 (eventually) to a 6.5TD as its a great off-road engine, and my CC to a cummins because I want more power for my tow rig.

 

[82355]

Why Nebraska? If you do move to Nebraska, there is no emissions testing. Why not just buy a factory 6.2 Blazer?

Martin

 

[2INSANE]

I heard the banks 6.2 turbo top boost is at a lower rpm, which would be ideal for off-road.

And the 6.5 turbo top boost is at higher Rpms, which would be good for long travels.

That's just what I heard...

 

[K5-CJ5]

I heard the banks 6.2 turbo top boost is at a lower rpm, which would be ideal for off-road.

And the 6.5 turbo top boost is at higher Rpms, which would be good for long travels.

That's just what I heard...

This is true, unless its the 90-92 6.5 which is the same turbo as the sidewinder, even made by banks for gm. There are, however, ways to spool a turbo faster with minor mods.

 

[2INSANE]

This is true, unless its the 90-92 6.5 which is the same turbo as the sidewinder, even made by banks for gm. There are, however, ways to spool a turbo faster with minor mods.

Ha! I knew that bird whispering in my ear was good for somethang! Lol!