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Message: [QUOTE="golfer, post: 316803, member: 266"] regardless of what anyone thinks... 6000rpm is hardly "high rpm"... go find a big block that DOESN'T spin 6000rpm off the showroom floor... so while our engines have heavier than gasser reciprocating components...we're NOT spinning these things to high rpm [I]by gasser standards[/I]... if high rpm were an (reliability) issue with the 7.3L...I'm prettttty sure we'd (all) have seen all the carnage on the interweb...piston pins pulling out of pistons...[I]stretched [/I]connecting rods (LOL)... the problem with the 7.3L is weak rods..weak in compressive strength....combined with a slow injection system...has forced tuners to try and make POWER at the available/conventional "diesel" rpm range...which makes more tq than the rods can handle... make that same power at higher rpm...by DEFINITION the tq comes way down...more wheel speed (for the pullers), higher shift points (for the racers)...and the ability to spool large(r) turbo's and stay on top of them. also...since hp is defined as WORK PER TIME (not per rpm)...but hit your stopwatch...TIME... example: cut the injection volume in half...and do twice as many injections...you just made the same (probably significatnly more) [B]power[/B] at 2x the rpm as the 'other' guy...with less stress on the ([I]this[/I]) engine...since this engines Achilles' heel is (too much) torque. one of the questions was x amount of torque at low rpm vs the same tq high(er) rpm...and why one is harder on the engine than the other... eh...aside from the fact that's it's unconventional to make peak tq at high rpm... while the physical stresses would be identical on the rod (etc)...the TIME that those stresses are on the rod can/will allow the weaknesses in materials manifest & show a failure. a good portion of the time spent tuning is limiting our low end torque..again..[I]we're not looking to neuter a truck[/I]...but on trucks that can make (do/have made) >2000lbft...big whoop...pull fuel in the lower rpm such that tq is at a reliable level (1000-1100lbft for forged rods is gravy)..and instead of making 1700lb ft, and stressing the engine...just hold that torque as loooong as possible... and what happens when you make decent torque at higher and higher rpm? your hp just jumped up a ton. 1000lbft at 1500rpm= 285hp 1000lbft at 2000rpm = 380hp 1000lbft at 4000rpm= 761hp 1000lbft at 6000rpm= 1142hp and to hopefully quell any torque versus hp arguments... chose what fits your [B]application[/B]...but I'm pretty sure this discussion is focused on 7.3L [B]competition[/B] vehicles (this IS in the [I]7.3L Upgrades & Aftermarket[/I] section)...not tow vehicles...and not 16L OTR tractors.. with rods the size of my leg...that don't spin more than 1500rpm, and need 12 gears to make use of that. so shut it ;) [/QUOTE]