Turn up turbo boost?

[scaryfasthummer]

I'm thinking of rebuilding a 2000 6.5L TD with low compression (18:1) pistons, head studs and crank girdle. My plan is to use a mechanical 6.5 milspec pump as I dont want any computers on my race truck; less to go wrong in the middle of North Africa.

My question is how do you turn the boost up? Is it done with a mechanical waste gate? I've been told I should be able to run up to 18psi reasonably safe with the studs and girdles.

Any thoughts welcome!

Cheers from over here,
Cole

http://scaryfasthummer.googlepages.com for pics/story of our racing Hummer.

[Craig M]

Cole;

Unclear of your question. Your web site says you have the Whipple supercharger on your 6.2. Our "normal" 6.5's have the turbo, not a supercharger. What boost are you refering to? Do you plan to switch to a turbo?

[scaryfasthummer]

Thanks for the web visit, I hope you enjoyed it. Yes, I am running a whipple charged 6.2 at the moment with mechanical 6.5 pump and 6.5 injectors. I have 2000 "Y" numbered 6.5 turbo engine coming from the states. It is a complete drive train; transfer case to engine fan. Problem is it got hydrolocked; sucked in water through the dust port on the aircleaner. The owner (a friend of mine) stopped IMMEDIATLY, removed all the glow plugs and removed all the water. The engine drove home another 60 miles just fine, if a little rough. Its down on compression in 3 cylinders. My thought is that it probably has three bent con rods and otherwise okay. My plan it to tear it apart and if its in servicable condition, rebuild it for racing.

I LOVE my supercharger but its not "legal" by SCORE or FIA racing regs. The 6.5 turbo diesel is. The supercharger will be for sale once I get the new engine in. If I could get somewhere in the neighborhood of 300hp out of the 6.5TD I would be delighted.

I know you can get huge improvements with a computer upgrade but I am really trying to avoid computers all together. Erg Chebbi, in the Sahara, is a loooooong way from anywhere and not the place to try and fix your pmd, etc.

Hope this clears it up, thanks for any help/insight.

Oh, FYI; my friend is replacing the 6.5td with a Duramax. THey bolt right in to H1's now since AMG built the Apha model (if you buy the new motor mounts, etc). I wish I could afford a D-max myself but if wishes were horses, beggers would ride (as my mother used to say!)

[DA BIG ONE]

Forget any GM turbo pushing 18 lbs boost efficently, the big one GM-8 is good to about 15lbs+- boost, starts superheating charge air @ about 16psi.

Holset turbos from what I've seen will give you the biggest bang for the buck using high pops.

DB-4 mech (marine) pump would be nice if you can keep everything cooled down

[scaryfasthummer]

Forget any GM turbo pushing 18 lbs boost efficently, the big one GM-8 is good to about 15lbs+- boost, starts superheating charge air @ about 16psi.

Holset turbos from what I've seen will give you the biggest bang for the buck using high pops.

DB-4 mech (marine) pump would be nice if you can keep everything cooled down

Thanks for the info! THe Hummer comes with the DB-6. You'll have to talk me through some of the basics as Im not a turbo guy at all. What kind of pressure should I get out of the DB-6? Do you "turn it up"? e.g., a supercharger can be turned up with a smaller pulley.

Do any of the other turbos (db-8) bolt on in the place of the rear mounted turbo or is the mounting of the db-6 unique?

Thanks again!

[scaryfasthummer]

Sorry, I'm retarded: I meant GM-6 v "DB-6"

must be from driving on the wrong side of the road for so long:D

Cole

[DA BIG ONE]

Sorry, I'm retarded: I meant GM-6 v "DB-6"

must be from driving on the wrong side of the road for so long:D

Cole

The DB4 injection pump is the highest output mech IP there is for 6.2/6.5 motors but for marine application.

The GM8 is biggest turbo for 6.2/6.5 from factory, someone else has to chime in about it fitting your hummer manifold. The GM 6 maybe there because of space constraints, not sure, maybe to detune it a little too.....

I'm always screwing up cause I have sometimers, sometimes I remember, sometimes I don't, an illness for those of us to use on the wife as an excuse why not to do something.

[gmctd]

You might check into the Dmax and Powerstroke for hi-center rear mount turbos - possibly you could adapt one.

That and the marine DB2 should easily get ya 300hp on a splay-capped and balanced 18:1 desert-rat motor