TT rear axel worm drive

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Joined: Sun Jun 23, 2019 5:24 pm
First Name: James
Last Name: Meinert
Location: Milwaukee

TT rear axel worm drive

Post by » Sun Jun 23, 2019 9:17 pm

Looking for a TT rear axel worm drive complete

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First Name: Tom
Last Name: Strickling
Location: New Philadelphia Ohio

Re: TT rear axel worm drive

Post by tom_strickling » Mon Jun 24, 2019 8:24 am

Do you just need the worm and the ring or a complete rear end??

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Joined: Sun Jan 06, 2019 11:14 am
First Name: Henry
Last Name: Petrino
Location: Modesto, CA

Re: TT rear axel worm drive

Post by HPetrino » Mon Jun 24, 2019 10:07 am

A couple of thoughts as you shop for a rear end:

They are not all the same. Early TT rear ends have a bead on the clam shell at the axle tube opening, later ones do not. Early TT rear ends have a differential shaft with two differential gears, later units have a differential spider with four gears. Early units have a plain axle housing cap, later units have a hole and plug. Also, there are two stock gear ratios, 5 1/16:1 (slow, harder to find) and 7 1/4:1 (slower, easier to find).

So, the point is be sure to get what you really want. Getting one that works is probably not too difficult, getting a specific set-up might be a little more challenging.

Good Luck!!

Burger in Spokane
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Re: TT rear axel worm drive

Post by Burger in Spokane » Mon Jun 24, 2019 10:48 am

Putting Henry's comment into perspective, a 7:1 ratio gear set will have your engine
maxed at 20mph. Even slower if it is not rebuilt and balanced. A rebuilt and balanced
engine with a 5:1 gear set will do a comfortable 35 and have an upper end approaching
50. While the gear set is an important consideration, Model T engines were not balanced
at the factory - road conditions limited speed to a level that made doing so a waste of
money - so now, when we drive them on nice paved roads, we discover just how unbalanced
those engines were when we get them up to speeds they were not exposed to in pre-war days
and try to shake themselves apart going down the road.

26 2016 aug 25 2.jpg
More people are doing it today than ever before !

Erik Barrett
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Location: Auburn, Ca.

Re: TT rear axel worm drive

Post by Erik Barrett » Mon Jun 24, 2019 2:46 pm

What Burger said. Unless you are doing nothing but parades, you want the high speed gear set.

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A Whiteman
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Re: TT rear axel worm drive

Post by A Whiteman » Mon Jun 24, 2019 4:54 pm

One other thing to remember is the size of tires you use!

Some have taller side walls - they effectively increase your final ratio over the road compared to lower side wall heights.

A club member with the same worm ratio as mine, but with lower height side wall tires actually went faster than me over all as he went up hills quicker ! …

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