What is all that you could do to a 6.5 turbo to get the most possible torque out of it? i know it wont be nothing close to the cummins.

 

well first you want the engine to breathe so a 4 Inch exhaust from Warpspeed, Heath, SS Diesel, or Kennedy diesel is a must. next a 1996+ air intake or AFE intake because you need clean air to feed the engine. next you probably want a chip to reprogram the ECM to get more power. Heath is the best but BD, SS Diesel, and Kennedy make good ones too.

to compensate for more fuel you should upgrade your fuel injectors to Marine Versions that should add about 30 to 40 HP. to get the fuel to the engine you should get a HD lift pump so the engine is never thirsty for fuel. the factory boost control isnt very good so a Turbo Master from Heath will make the engine have a more linear Boost curve and not just spikes.

you can upgrade your turbo to a HX-35 off a cummins or another popular option is the A Team turbo. this will make you spool up faster and make more boost. to cool the air coming from the turbo you should make or get a intercooler. this will drop the temps and will add power. another way to get cooler temps is to get a gasket off a J-code 6.2L diesel and get a F-code intake manifold of a 6.5L. this will block the EGR which will make the air cooler and make less restriction.

the next way to make power is with injectables. Nitrous, Propane, Water/Meth will all increase power but they can be dangerous so use with caution. too much nitrous and you could be looking for a new block. too much propane and you could be looking for new pistons.

after doing this you ABOSULUTELY NEED GAUGES. you need to be able to monitor what is going on because the 6.5 engine isnt desighned to make all this power. head studs and heavy duty gaskets are a must too

 

Woody35 is right -on w/power upgrades... if you have the jack to spend. If your on a McBudget like me you can opt for the poor boy route and chop the down pipe rear of the connector and run 4in all the way back. Go to the auto parts store and into the limp wristed tuner section, pick-up a high-flow washeble cone type air filter, make sure you get the 1 that has the spacer rings for 1-size-fits-all. Once these are installed you should see a dramatic increase. Another trick that is unpopular on the GM sites is useing a piece of expandable cord (bungee ect) to help keep the factory blow-off valve from opening up to soon. This last one by it's self knocked 2 seconds off my 0-60 time on a 99' crew cab 1ton 4x4. You don't want it to stay closed all the time so a little time to tune it just right will be required.
I could out-pull and outrun a 1st gen PSD and any stock 91 or older cummins with these mods and got 18mpg w/33's.

 

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