Turbine Doc
Just Another Diesel Guy
Not to disagree, well maybe a little; as goes up speed so does drag U know that, 150+ mph in a full size/full weighted GM truck Bonneville speed over a 3 mile course @ 5000' elevation IS a workout from reports of those that went there last year the time for the LSR to get to 100+ is pretty impressive .
I've not lowered CR myself I had thought about it at one time even have the 18:1 pistons out in the shop, I'm still at stock CR been towing that way for years though I self limit to 14 psi peak boost when moving my 18K# big load 2x a year mostly at seal level running to 300' or so at finish of my trips.
Bill specs re-mans he gets for folks to 22:1 and runs some higher than that in some of his shop trucks which are daily mountain drivers & tow rigs.
From what I recall when Bill was drag racing the 6.5 he was down to 14.5 CR or some such low CR, but running maybe 60 psi boost ??? on a special turbo, special IP & injectors & it took like 15 minutes to get it to get hot enough to make runs, but once hot it could make front wheels off ground launches.
As for cam Bill is back to a stock cam, as "special one" talked about in DP article didn't work as hoped, I don't remember what he said about valves & springs if he's going back stock there, probably running stiffer springs for 4000+ rpms he's running he did discuss that a while back.
Another member visited the shop that makes cams for Bill says according to the cam shop owner, he thinks that was about 90th purpose grind & valve combination's he's seen used on the 6.5 over the years, by different grind customers coming back to the stock grind when all is said & done as best cam overall mirroring Bill's comment last month when I revisited cams with him.
A purpose built cam/valve combo is probably out there waiting to be found with the magic combination for strip, more than a few have tried it the 6.5 has been around a while, sacrificing the vehicle utility to a sport driven vehicle; this is performance area of the forum bound to be someone that unlocks the key given enough resources and doggedness to make a point.
I've not lowered CR myself I had thought about it at one time even have the 18:1 pistons out in the shop, I'm still at stock CR been towing that way for years though I self limit to 14 psi peak boost when moving my 18K# big load 2x a year mostly at seal level running to 300' or so at finish of my trips.
Bill specs re-mans he gets for folks to 22:1 and runs some higher than that in some of his shop trucks which are daily mountain drivers & tow rigs.
From what I recall when Bill was drag racing the 6.5 he was down to 14.5 CR or some such low CR, but running maybe 60 psi boost ??? on a special turbo, special IP & injectors & it took like 15 minutes to get it to get hot enough to make runs, but once hot it could make front wheels off ground launches.
As for cam Bill is back to a stock cam, as "special one" talked about in DP article didn't work as hoped, I don't remember what he said about valves & springs if he's going back stock there, probably running stiffer springs for 4000+ rpms he's running he did discuss that a while back.
Another member visited the shop that makes cams for Bill says according to the cam shop owner, he thinks that was about 90th purpose grind & valve combination's he's seen used on the 6.5 over the years, by different grind customers coming back to the stock grind when all is said & done as best cam overall mirroring Bill's comment last month when I revisited cams with him.
A purpose built cam/valve combo is probably out there waiting to be found with the magic combination for strip, more than a few have tried it the 6.5 has been around a while, sacrificing the vehicle utility to a sport driven vehicle; this is performance area of the forum bound to be someone that unlocks the key given enough resources and doggedness to make a point.
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