The Ford Barn

M2M · 07-20-2019, 09:53 PM

[QUOTE=Synchro909;1779088]The restorer of my '28 Tudor fitted a 3.54 diff. A later owner fitted a 26% Mitchell O/D. I am going back to reduce the overall ratio because it is too highly geared as it is in O/D. Economy is poor and it hates hills. This is the same as you experienced.
By going back to 3.78, I am reducing the overall ratio by about 3.6%. By putting 5.00X19 wheels and tyres on it, I'm dropping by 3% - about the same. I have the wheels ready to go (the old 21" tyres are worn out) so I will try that option first ($$$).Before anyone criticises me for putting 19" wheels on a '28 car, this car is a go-er, not a show-er![/QUOTE

You've probably considered it I'm sure but another option could be going to 4.11 then adding BF GOODRICH 550x19 bias ply which effectively gives you approx. 3.9 (a guess without doing the maths). If I had a mitchell I would want it to pull most hills in o/d. Better to be geared a bit low than a bit high.

M2M · 07-21-2019, 10:53 PM

Coker has a $60 rebate deal currently on a set of 4 tyres, see:

https://www.cokertire.com/media/adsp...own_form_2.pdf

07-20-2019, 09:53 PM	#21
M2M Senior Member Join Date: Jul 2012 Location: Australia/USA/EU/Soviet Russia Posts: 1,105	Re: changing to 5.50 Bias Ply = changing to 3.54 ratio [QUOTE=Synchro909;1779088]The restorer of my '28 Tudor fitted a 3.54 diff. A later owner fitted a 26% Mitchell O/D. I am going back to reduce the overall ratio because it is too highly geared as it is in O/D. Economy is poor and it hates hills. This is the same as you experienced. By going back to 3.78, I am reducing the overall ratio by about 3.6%. By putting 5.00X19 wheels and tyres on it, I'm dropping by 3% - about the same. I have the wheels ready to go (the old 21" tyres are worn out) so I will try that option first ($$$).Before anyone criticises me for putting 19" wheels on a '28 car, this car is a go-er, not a show-er![/QUOTE You've probably considered it I'm sure but another option could be going to 4.11 then adding BF GOODRICH 550x19 bias ply which effectively gives you approx. 3.9 (a guess without doing the maths). If I had a mitchell I would want it to pull most hills in o/d. Better to be geared a bit low than a bit high. __________________

07-21-2019, 10:53 PM	#22
M2M Senior Member Join Date: Jul 2012 Location: Australia/USA/EU/Soviet Russia Posts: 1,105	Re: changing to 5.50 Bias Ply = changing to 3.54 ratio Coker has a $60 rebate deal currently on a set of 4 tyres, see: https://www.cokertire.com/media/adsp...own_form_2.pdf __________________