The Ford Barn

Synchro909 · 09-24-2019, 06:15 PM

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Good to hear you have finally gotten it out of the garage. I've been wondering how things were going.
IMO and experience, if you want to do trips like Alaska, you'd be a looong way better off putting in a counter balanced crank shaft and rods (invisible). Whether you run them on babbit or inserts, I don't think makes all that much difference. The weakest point in the bottom end is the middle main bearing so I pressure feed it but not the others. I'd also go for a head with higher compression than a police head. 6:1 sounds good to me. A mild cam is also invisible and makes a world of difference to these motors. You wouldn't believe how much!
With a motor like that and wanting to travel at the sppeds you mention, I think a higher diff ratio is a must. 3.54 at least. 5.5 tyres increase your overall gearing by about 5%. A 3.54 diff increases your gearing by about 6% (from memory) over the the 3.78 ratio. If you do both, you have 11% higher gearing with the advantage of more rubber on the road. At the same revs you would have been doing at 45mph, you would then be doing 50 which I think is enough in a car with poor (by modern standards) brakes, suspension and steering.
Another alternative is to go to a 3.27 diff. That will give you a gearing 15% higher than standard so you are in the same ballpark. 3.27 with the larger tyres gives you near enough, 20% higher gearing which is getting close to having an O/D (26ish%) in there but you can't shift down for hilly terrain or traffic without going back to 2nd gear (not recommended).
As you know, I have done plenty of long distance touring and would be glad to discuss this with you. I think you have my number.
If you have the $$, you can put in the Mitchel synchro cog house for easier gear changing. It cannot be distinguished from an original gearbox from outside and the closer spacing between 2nd and 3rd gears is a winner.
There are lots of options to mull over!

09-24-2019, 06:15 PM	#6
Synchro909 Senior Member Join Date: Jun 2014 Location: Melbourne, Australia Posts: 8,434	Re: My 1st decent drive of Model A and discussion Sponsored Links (Register now to hide all advertisements) Good to hear you have finally gotten it out of the garage. I've been wondering how things were going. IMO and experience, if you want to do trips like Alaska, you'd be a looong way better off putting in a counter balanced crank shaft and rods (invisible). Whether you run them on babbit or inserts, I don't think makes all that much difference. The weakest point in the bottom end is the middle main bearing so I pressure feed it but not the others. I'd also go for a head with higher compression than a police head. 6:1 sounds good to me. A mild cam is also invisible and makes a world of difference to these motors. You wouldn't believe how much! With a motor like that and wanting to travel at the sppeds you mention, I think a higher diff ratio is a must. 3.54 at least. 5.5 tyres increase your overall gearing by about 5%. A 3.54 diff increases your gearing by about 6% (from memory) over the the 3.78 ratio. If you do both, you have 11% higher gearing with the advantage of more rubber on the road. At the same revs you would have been doing at 45mph, you would then be doing 50 which I think is enough in a car with poor (by modern standards) brakes, suspension and steering. Another alternative is to go to a 3.27 diff. That will give you a gearing 15% higher than standard so you are in the same ballpark. 3.27 with the larger tyres gives you near enough, 20% higher gearing which is getting close to having an O/D (26ish%) in there but you can't shift down for hilly terrain or traffic without going back to 2nd gear (not recommended). As you know, I have done plenty of long distance touring and would be glad to discuss this with you. I think you have my number. If you have the $$, you can put in the Mitchel synchro cog house for easier gear changing. It cannot be distinguished from an original gearbox from outside and the closer spacing between 2nd and 3rd gears is a winner. There are lots of options to mull over! __________________ When all is said and done, more is said than done. That's why we judge people on what they do, not what they say. I sometimes wonder what happened to the people who asked me for directions. If I am not in trouble, I've done something wrong.