Shifting

[Jackpine]

Originally Posted by jdjam

WOT setings

1-2 5200rpm
2-3 5200rpm
3-4 5000rpm

I don't know that this will help your "hard" downshift from 4th to 2nd when passing, but I think your WOT shifts are all too high. Torque and HP are generally decreasing above 5000, so I'd recommend 1-2 and 2-3 at 5100 and drop the 3-4 shift down to 4600. Bill said once that the 3-4 shift is stressful on the transmission and he seems to prefer it down there.

Set the rev limit at 5500, because you start to get Torque Converter ballooning at 5400. However, the rev limit needs to be at least 400 above the highest WOT shift.

Finally, load your custom tunes without reloading any of your "previous settings" and check the WOT shifts and rev limit. I'd tend to stay pretty loose to what Bill put these at and my guess is, they will be quite close to the figures I just gave you.

I honestly don't know if the sudden downshift from 4th to 2nd is bad or good, but as 88racing said, the transmission is just doing what you're telling it to. My gut tells me the "lurch" is putting stress on things, so I tend to feed the gas in just a bit slower, giving me a transitional 4-3 downshift and then a 3-2 downshift (if the load and speed are right). I'm happy to have someone explain to me why this is not necessary if they feel this is the case.

- Jack

[jdjam]

Thanks J&J. I usually drive like you were saying. Saying "stomp on it" probably gave the impression I drive it hard all the time.
The WOT settings I mentioned above are on the gryphon right out of the box and the rev limit is set @ 5600. I never messed with them.

I set everything to what you suggested before I left work this afternoon. Wonder why they were high?

[Jackpine]

Originally Posted by jdjam

Thanks J&J. I usually drive like you were saying. Saying "stomp on it" probably gave the impression I drive it hard all the time.
The WOT settings I mentioned above are on the gryphon right out of the box and the rev limit is set @ 5600. I never messed with them.

I set everything to what you suggested before I left work this afternoon. Wonder why they were high?

I'm going to say it's because you wanted Bill to give you "max performance", which those settings probably will (except I'm just a bit puzzled at the 3-4 5000 rpm upshift number). As I said, the torque and HP curves are falling at around 5K, but they don't fall too fast, so setting the shift points at 5200, moves the "average" RPM (before and after the shift) near the max output point.

I can only say that a 5000K shift for 3-4 will probably keep you in 3rd gear until maybe 100+ mph. Again, this feels like an "extreme" performance tune, and I'm a Grandpa, so maybe this is the difference.

Notice though, the max rpm IS 400 above the highest shift point. And, the short time above 5400 is not really going to hurt anything unless you ALWAYS mash the pedal to the floor, each and every day.

So, you know how it behaves with the tune set up the way Bill thought you wanted it (it's a bit of a guessing game). Give the settings I suggested a try and maybe come to some in-between conclusion if you don't like them.

- Jack

[jdjam]

Well, some sort of magic happened. Thanks for the logic and help.

Love the Gryphon. Feels like the truck went on a diet and lost a thousand pounds. Running great.

[Jackpine]

Originally Posted by jdjam

Well, some sort of magic happened. Thanks for the logic and help.

Love the Gryphon. Feels like the truck went on a diet and lost a thousand pounds. Running great.

All I can say is - good! (Whatever you did).

- Jack