Shifting low to high

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GregDeK
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* REQUIRED* Type and Year of Model Ts owned: 1923, aka Dust Bowl Special, very low mileage original 1915 roadster & an IKEA truck (IKEA because I have to put it together...)
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Shifting low to high

Post by GregDeK » Thu Jun 20, 2024 1:14 pm

I've been driving Ts for a while, and there is one thing I've never mastered. Not sure if it's ignorance or whether it's just not going to happen.

Is there a way to shift from low to high without the engine lugging as it goes into high gear? I never seem to get it right.

Thx!

Greg


Moxie26
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Re: Shifting low to high

Post by Moxie26 » Thu Jun 20, 2024 1:25 pm

Try this..... When shifting from low to high, reduce your spark by half as you let up on the clutch and keep the throttle in the same position until you get to the speed you want and retard your throttle... Just so you don't get a traffic ticket.


m_p_dean@yahoo.com
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Re: Shifting low to high

Post by m_p_dean@yahoo.com » Thu Jun 20, 2024 3:14 pm

I don't believe the low/high shift is ever going to be as we expect it. Imagine in a more modern car starting in 1st or 2nd gear, getting up some speed (but not over revving), then dropping it into 4th (direct drive in most modern 4 or 5 speeds). It's just never going to be as smooth as using the gears in between. It can be improved with technique, but never perfect. Maury Dean


TXGOAT2
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Re: Shifting low to high

Post by TXGOAT2 » Thu Jun 20, 2024 3:56 pm

It can be done very smoothly when everything is in order. Practice on level ground, and use the throttle lever to match the engine speed to the car speed in high gear. Avoid over-revving in Low. Normal Low to High shifts on level ground occur around 7 to 8 MPH, so you don't want full spark advance. A car that is out of tune or has worn linkages or mis-adjusted band linkages will be harder to shift smoothly. At low speeds in high gear, avoid full throttle. Performance camshafts may make the engine less responsive at low RPM. Every car is a little different, but by paying attention and practicing, you can achieve very quick, smooth shifts without losing forward momentum. Avoid starting the car up steep slopes whenever possible.

I believe that low gear is 3:1, while high gear is 1:1, ignoring the ring & pinion reduction.
If that's correct, shifting to high at about 8 MPH will drop the engine speed to about 300 RPM, which is quite low, but acceptable at light throttle and with the spark not over-advanced. The engine needs to be in good tune to pull smoothly at low speeds.


Jerry VanOoteghem
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Re: Shifting low to high

Post by Jerry VanOoteghem » Thu Jun 20, 2024 4:03 pm

You can get seamless shifts by starting off in low, then simply pausing in neutral for a moment, letting up on the throttle, and waiting for the engine to slow down to match the speed of the car. Then, lift your foot, letting the car into high gear, and accelerate from there. Do NOT slip or feather the high speed clutch.


TXGOAT2
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Re: Shifting low to high

Post by TXGOAT2 » Thu Jun 20, 2024 4:04 pm

You have to teach your right hand to do what your right foot normally does.


John kuehn
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Re: Shifting low to high

Post by John kuehn » Thu Jun 20, 2024 5:14 pm

It takes a little practice and thinking like a T! I tend to slow the engine a little when shifting into high. I watched my older friend who was in his 60’s in the 1970’s when I started driving the 24 Coupe I inherited. It was amazing how he could drive the car and be so smooth in shifting the car. It was really seamless.

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