Turbo 6.2 (6.5 turbo setup)

[Mattman2010]

I have a military J code 6.2l diesel that I am wanting to install a 6.5 turbo setup on. I have everything figured out but the A/C box. I have seen people say use an S10 a/c box. But I am not sure what year A/C box you would use, and I am not really sure what all would need to be done to get it to work. I have searched several places and have not found any kind of solid information, or pictures of the A/C box installed.

If you could show me links to this swap done, or any information about how to go about doing the S10 a/c box swap that would be great!

Matt

[lindstromjd]

I've been curious about this for a while, too. Apparently, you have to get the S10 box, take your C10 box off, cut them both up, and splice them together with some fiberglass bondo. Then you use the S10 A/C evaporator, and it still mounts up to your firewall because of the C10 base.

[madcow75]

I am doing the same 6.2L J code with a 6.5L turbo setup. My question is where did you run the oil line coming from the turbo. Original location is to the top front of the 6.5L block. Did you drill and tap a hole or use an alternative location? I am using a 89 6.2L block with a 93 6.5L turbo top end.

[odee]

I've done one with the s10 housing. Split the the stock one and the s10 spliced together. I used the evap from my truck. I'm fixing to do another with the cummins swap in my newest crew dually.

[Mattman2010]

Originally Posted by madcow75

I am doing the same 6.2L J code with a 6.5L turbo setup. My question is where did you run the oil line coming from the turbo. Original location is to the top front of the 6.5L block. Did you drill and tap a hole or use an alternative location? I am using a 89 6.2L block with a 93 6.5L turbo top end.

I have seen people put a "T" out of the back of the drivers side block where the oil pressure sender is. Then put the oil sending unit on one side, and a hose to the turbo on the other side.

Originally Posted by odee

I've done one with the s10 housing. Split the the stock one and the s10 spliced together. I used the evap from my truck. I'm fixing to do another with the cummins swap in my newest crew dually.

Do you have any pictures of this? I would really like to see how you went about doing the cutting and splicing.

[Edahall]

Here's a recommendation for those interested in installing a 6.5 turbo on their 6.2.

The bottom ends on both the 6.2 and 6.5 are not the strongest. The introduction of the factory turbo that was installed on the 6.5L seemed to put the bottom end on these engines over the edge. There were a lot more bottom end failures with the 6.5 turbo diesel. GM was trying to compete with Ford and Cummins and they slapped on a turbo on these engines without strengthening the block.

These engines tend to be a lot more durable non aspirated but if you need the power, here's my recommendation.

1. Fix and repair any cracks in the bottom end. Cranks in the main webs can be repaired using LOCK-N-STITCH. The cranks should be repaired because if not, they'll keep growing and one day, the whole bottom end will fall out.

2. Install a Fluid Damper harmonic balancer.

3. Consider lowering the compression ratio to about 18:1.

Cracked block image:


LOCK-N-STITCH repair insert


Crack repaired


I should mention that as long as the cracks are not out of the bolt hole or are not at the register cut, this repair can be performed. Also, it's a good preventative measure to do all six outer center holes whether cracked or not.

[madcow75]

Also a good preventative mantainence that I will be installing on my 6.2L bottom end is a stud girdle, this will help with cylinder wall flexxing and cracking. I have checked mine and no cracks yet but I still will add one.

What is stock compression in a 6.2L.

[sierra4x4]

I have to agree with Edahall. The 6.2/6.5's don't hold up very well with a turbo. Every 6.5T that I have opened up had cracks in the block and most of the heads. The NA 6.2/6.5's seed to run forever.

[Edahall]

Originally Posted by madcow75

Also a good preventative mantainence that I will be installing on my 6.2L bottom end is a stud girdle, this will help with cylinder wall flexxing and cracking. I have checked mine and no cracks yet but I still will add one.

What is stock compression in a 6.2L.

Stock compression ratio on a 6.2L is 21.5:1

[Corts60]

I really appreciate this thread. I thought only the 5.7's couldn't handle the turbo. I thought the 6.2/6.5's were good to go. Stock compression on the 5.7's were 22:1. I wonder if you could lower the 5.7's to 18:1 compression and turbo that sob.

[Edahall]

Originally Posted by Corts60

I really appreciate this thread. I thought only the 5.7's couldn't handle the turbo. I thought the 6.2/6.5's were good to go. Stock compression on the 5.7's were 22:1. I wonder if you could lower the 5.7's to 18:1 compression and turbo that sob.

From what I've seen, the 6.2L in stock form can handle about 6-7 psi of boost and still be reliable. Over that, you're asking for trouble. Of all the turbos out there, the Banks turbo was by far the easiest on the engine but also produced the least amount of boost and power.

Lowering the compression would help and would allow more boost but there's still a limit and the limiting factor is the bottom end. A strong bottom end is the reason the 5.9 Cummins can produce well over 1000 hp and the 6.2L much less.

[Hoods69BadBowTie]

Yea sorry got no info to help ya out. But a pretty cool thread with some good info in it. I have been debating a 6.5 turbo swap into my K5 blazer. I think I will just put a new 6.2 in it and call it good for now.

[406 Q-ship]

Originally Posted by Corts60

I really appreciate this thread. I thought only the 5.7's couldn't handle the turbo. I thought the 6.2/6.5's were good to go. Stock compression on the 5.7's were 22:1. I wonder if you could lower the 5.7's to 18:1 compression and turbo that sob.

I was dealing with the 5.7 diesels back when they were still under warrenty. DO NOT EVER PUT ANY BOOST TO A 5.7 UNDER ANY CIRCUMSTANCE!!!!! The only place a 5.7 Olds diesel should ever be is at the end of a chain under a boat. Funny thing, I was pulling the 5.7 out of trucks, Cadillacs, Oldsmobiles, and Buicks to convert them to gas engines (worked at a place that did smog legal gas conversion), we sold the running (some broken ones too) to a New Zealander who was using them for agraculture water pumps. When run at a steady RPM the olds diesel would live forever.