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Common Question what can I do to make more power with my 6.5
While not an expert I'll pass along what has worked for me and what I've learned from others RATDOC, GMCTD you out there Thanks for all the help.
1st question you have to ask yourself is what is your goal, power or speed, I'll list what I've done for power/longevity. Speed to me is best left to gassers, yes you can build a fast Diesel but at what cost in the long term, beat it up and it won't last. If you are here on the 6.5 forum you have an "old truck" 6.6 DMAXes are current offering since 2001. How much life do you figure you have in a higher mileage vehicle, not only has your engine been stressed but so has the rest of the running gear. Unless you have done a complete top down rebuild/inspection of the whole truck speed is going to cost you in the long run.
Before plopping down bucks get smart, visit other Diesel sites to see what works there running feud aside; there are some good folks at TDP, another good place to start is www.banksdiesel.com they have a lot of good education on the site. Power from a Diesel is tied to airflow which is why turbo and in really big engines turbo/supercharging is a necessity, while you are making power you also want to keep combustion temps under control to keep the engine from self destructing.
My truck easily pulls 12K which is a lot for a L56 K1500.
1st thing I did was to install a free-er exhaust Banks 3.5" cat back system, this reduced backpressure and lowered exhaust temp, the factory down pipe gets replaced with a mandrel bent one, factory pipe look like it had been run over by our truck. Other vendors out there for this system check around, Banks was pricey but at the time I did not know better. free flowing air filter was also part of that kit Amzoil or K/N your choice another site had a pretty long study end result was Amzoil had better result but K/N wasn't far away in my opinion.
The L56 EGR engine upper intake needs hogging out it has (2) 1/8" wide x 3" long slits beside the EGR tower that the engine breathes thru, I removed the excess with a shortened metal cutting jig saw blade to reduce mess that would come from a air or dremel grinder. make sure it's hospital clean before reinstalling, don't feed the engine metal chips it can't digest. Also replace "donut gasket" ring that sits between upper and lower intake that seals EGR port/tube, hard to see under the soot but its there. I left a little webbing 180 deg apart to add support to the center tower.
Later 6.5s OBDII with electronic IP have problems with PMD/FSD overheat relocate on remote heat sink ASAP if you can't afford that, at a minimum remover plastic "Turbo Power" dress up cover to allow more flow across PMD.
Gages, not enough can be said about importance, if you are a data nut like me more is better, boost & EGT at a minimum, trans if you are frequent towing
Do no more mods than exhaust restriction removal without them!!!
You need to know when to back off Max EGT post turbo location 1000F.
If pre 97 truck and will heavy/frequent tow consider up grade to dual H2O thermostat and HO 130gpm water pump, better fan clutch.
Boost control allows fake out to PCM IAT so boost stays in longer, factory PCM program backs out boost when you need it most, max boost without Intercooling in my opinion 10 psi will explain later. Mechanical WG controls are available for mechanical IP and WG trucks
Remote bypass oil filt setup, on K (4x4) series IMHO a necessity just to get access to the filter, stock adapter does not allow easy access, bypass filt has second element for better filtration plus extra oil helps reduce operating temp from more oil to be cooled and passive cooling as filter bodies are in cooler air stream location than under engine.
While not an expert I'll pass along what has worked for me and what I've learned from others RATDOC, GMCTD you out there Thanks for all the help.
1st question you have to ask yourself is what is your goal, power or speed, I'll list what I've done for power/longevity. Speed to me is best left to gassers, yes you can build a fast Diesel but at what cost in the long term, beat it up and it won't last. If you are here on the 6.5 forum you have an "old truck" 6.6 DMAXes are current offering since 2001. How much life do you figure you have in a higher mileage vehicle, not only has your engine been stressed but so has the rest of the running gear. Unless you have done a complete top down rebuild/inspection of the whole truck speed is going to cost you in the long run.
Before plopping down bucks get smart, visit other Diesel sites to see what works there running feud aside; there are some good folks at TDP, another good place to start is www.banksdiesel.com they have a lot of good education on the site. Power from a Diesel is tied to airflow which is why turbo and in really big engines turbo/supercharging is a necessity, while you are making power you also want to keep combustion temps under control to keep the engine from self destructing.
My truck easily pulls 12K which is a lot for a L56 K1500.
1st thing I did was to install a free-er exhaust Banks 3.5" cat back system, this reduced backpressure and lowered exhaust temp, the factory down pipe gets replaced with a mandrel bent one, factory pipe look like it had been run over by our truck. Other vendors out there for this system check around, Banks was pricey but at the time I did not know better. free flowing air filter was also part of that kit Amzoil or K/N your choice another site had a pretty long study end result was Amzoil had better result but K/N wasn't far away in my opinion.
The L56 EGR engine upper intake needs hogging out it has (2) 1/8" wide x 3" long slits beside the EGR tower that the engine breathes thru, I removed the excess with a shortened metal cutting jig saw blade to reduce mess that would come from a air or dremel grinder. make sure it's hospital clean before reinstalling, don't feed the engine metal chips it can't digest. Also replace "donut gasket" ring that sits between upper and lower intake that seals EGR port/tube, hard to see under the soot but its there. I left a little webbing 180 deg apart to add support to the center tower.
Later 6.5s OBDII with electronic IP have problems with PMD/FSD overheat relocate on remote heat sink ASAP if you can't afford that, at a minimum remover plastic "Turbo Power" dress up cover to allow more flow across PMD.
Gages, not enough can be said about importance, if you are a data nut like me more is better, boost & EGT at a minimum, trans if you are frequent towing
Do no more mods than exhaust restriction removal without them!!!
You need to know when to back off Max EGT post turbo location 1000F.
If pre 97 truck and will heavy/frequent tow consider up grade to dual H2O thermostat and HO 130gpm water pump, better fan clutch.
Boost control allows fake out to PCM IAT so boost stays in longer, factory PCM program backs out boost when you need it most, max boost without Intercooling in my opinion 10 psi will explain later. Mechanical WG controls are available for mechanical IP and WG trucks
Remote bypass oil filt setup, on K (4x4) series IMHO a necessity just to get access to the filter, stock adapter does not allow easy access, bypass filt has second element for better filtration plus extra oil helps reduce operating temp from more oil to be cooled and passive cooling as filter bodies are in cooler air stream location than under engine.
