I don’t understand this power curve. Does anyone know the sweet spot for the 5.7 v8 torque curve? Like what’s the rpm to shoot for for being in final gear (.59 in the 6 speed I think) on the highway?
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What size tires on your built 200 w the 6 speed that hunts gears?310 HP at the wheels and at 4,400 ft elevation? Impressive for 381 at the crank at standard atmosphere.
FWIW, On a 'built' 200, I've found the 6spd hard to keep locked in 6th with anything other than a very light throttle. So flat road, no headwind, etc. I typically keep mine in manual 5th to prevent the wear from constant lock/unlock 6th or 6-5-6 hunt. Only when I know the conditions are right to I allow 6th.
285/70R17 is all, so 33s. Build image is in the avatar.What size tires on your built 200 w the 6 speed that hunts gears?
I think it’s less the wear from the 6-5-6 (or 8-7-8) shifting or torque converter locking and unlocking, but more from the heat being generated with the TC unlocks and that heat getting dumped into the fluid285/70R17 is all, so 33s. Build image is in the avatar.
True 'hunting' of gears is probably not the right term unless on a long highway grade. It's more the frequent lock/unlock in 6th. Transparent to most users, but it's a wear cycle with each event, no mater how small. And unlocking 6th happens with not a lot of added pedal pressure. But even around town I've found that the trans is biased to economy (aren't they all?) and achieves 6th too early, only to go back to 5th when traffic changes speed, slight inclines, etc. So rather than add the wear from all those cycles I just use manual 5th as my default and then push it up to 6th only when conditions warrant. Less delay when needing power is helpful too. Admittedly, I'll probably never see the benefit from this driving technique, but maybe the next owner will.
With the 8sp on the 570 I do similar. Out of the driveway is always manual (technically 'sport') 6th unless conditions warrant. For most 'local' highways I'll allow 7th. Only on interstates above say 70 do I allow 8th and even then only if it's open, steady-speed traffic.
Good point on the additional heat. I think it's probably both. Each actuation event, be it TC lock or shift solenoid, causes some non-zero amount of wear. An those wear particles end up in the fluid. The hard part is determining the net effect. Am I extending the life from 600k miles to 700k miles? If so, it's probably pointless. OTOH if I happen to have the nth percentile trans and extend the life from 150k to 250k then there's benefit. I suppose it's no different than 3UR OCI's at 5k vs 10k; the average owner will never see the gain. But that also doesn't negate that it's the best practice, with 'best' is defined as what is optimal for the truck we love.I think it’s less the wear from the 6-5-6 (or 8-7-8) shifting or torque converter locking and unlocking, but more from the heat being generated with the TC unlocks and that heat getting dumped into the fluid
Yes but the chart is kinda dumb since it looks like they didnt even start the pull at a low enough RPM to be useful, and show it in MPH instead of RPM. We dont even know what gear they used. Looks like they didnt start the pull until >3500 rpm.I think the chart from the OP was with a tune.