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Old 03-09-2015, 05:17 AM   #7 (permalink)
redpoint5
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Quote:
Originally Posted by jcp123 View Post
The slow speed bleed it what works best for me. Then again, I have an automatic, so I have little choice - kick the load up that high and the auto grabs a gear or two.
Do you have a device to monitor the load?

I have carefully studied how my 1998 Toyota Camry behaves when ascending a hill, and it won't downshift until 90%+ load is reached or RPM drops too low. It may drop out of closed loop mode on a very long and sustained 85+% load. I keep the load right at 80% on sustained hill climbs both to keep it in top gear, and keep it in closed loop mode. If the hill is very steep, then the car may downshift once RPM drops too low. It doesn't take much of a hill for the relatively tall-geared, heavy, and modestly powered Camry to loose enough speed that it drops down a gear.

The answer to the question is not either 80% load or slow speed bleed, but both. Sustain 80% load, and if the hill is too steep, you will slowly bleed speed.

Notice that as RPM drops, and without moving the throttle position, the engine load will increase. As RPM drops, smaller throttle openings are required to maintain the same engine load. That means you will need to constantly adjust the throttle in response to the engine RPM increasing or decreasing. Less throttle for lower RPM, more throttle for higher RPM; same 80-85% target load.
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