6.2 diesel

[Beefcake]

Got one of these in my 84 burb.

Im new to diesels, so bare with me. I want to do a complete rebuild, I've noticed the the 6.2 seems to have bottom end problems. I bought one with a shattered crank- for parts, only to find that this is common. I wonder if I should go with a steel crank then? Also, how far can I bore this sucker??... Does a larger cam help performance- Like a spark igniter?? And what kind of compression is optimal?? (everyone tells me that the more compression- the better) Then why not have dome pistons???

Also, How compatable are the heads from the 6.5L??? And, if I can just plop on the heads, can I also just grab a turbo 6.5L intake while Im at it???

thanks!!

joe

[grape]

the cranks break..........alot. the compression usually get's lowered when you're trying to make more power with boost, the gm engine is up around 22-1 stock, while later model ford, dodge and gm engines are in the 18-1 range. The pistons are flat top that usually come out of the hole anywhere from .003" to .009". The combustion chamber is actually nonexistant, just a flat head with two valves and the opening to the pre-chamber. yes 6.5 heads bolt on, but you need the injector lines because the angle of the injector changed so the lines are different. Only difference in any of the heads is the pre chamber which is based on power for the heavy dutys or mileage for the light dutys. However the pre chambers can be knocked out (carefully) and place in any cylinder head.

[arveetek]

I just now saw this post.

For more diesel information, visit www.thedieselpage.com It's the best place on the net for GM diesel guys.

www.coloradok5.com also has a dedicated GM diesel forum.

The 6.2L diesels can break crankshafts due to neglected and worn harmonic balancers. It is very critical to replace the harmonic balancer if the rubber starts looking like it's squished out or if chunks of it are missing. Also, some of the later model diesels used a crank pulley that was also full of rubber for more dampening effect. It needs to be replaced as well, for the same reasons. If you're doing a rebuild, now's the time to do it.

6.5L heads will bolt right on and give you more power.

You will actually want to lower the compression ratio if you plan to make a powerhouse. Lowering the compression won't give you more power, but make it last longer and allow you to build more boost, if you turbocharge it.

You can bore a standard 82-91 model 6.2L to .30" over. The 92-93 6.2L engines with casting numbers ending in 599 can be bored out to 6.5L dimensions. This particular block was made during the transition years from 6.2L to 6.5L.

There's only one cam option available for the 6.2L. If you send in your cam to Crane Cams, they'll regrind it for you. I've yet to hear from anyone if it truly makes a difference or not. The diesels don't respond to cam changes like the gassers do.

Good luck!

Casey