The Ford Barn

Synchro909 · 08-12-2016, 12:30 AM

I have just put my '30CCPU on the road expecting the speeds to be about the same as my '29 Phaeton but it seems to rev its tights

off. The speedo is reading way fast when compared to the GPS too.
I have seen somewhere, a method to find out what ratio is in there. As best I can recall, it involved marking a rear tyre at the bottom and the ground along side, jack up that wheel till it is just clear of the ground. take out the sparklers and turn the engine by the crank for 10 turns exactly. Have someone observe how many turns the wheel does It is usually 3 and a bit but it is that bit that is important. There was a diagram showing where the mark on the tyre ended up with the different ratios.
Does anyone have that info please.
I suspect mine is running a 4.11 ratio instead of the 3.78 I expected.

08-12-2016, 12:30 AM	#1
Synchro909 Senior Member Join Date: Jun 2014 Location: Melbourne, Australia Posts: 7,497	What diff ratio do i have? I have just put my '30CCPU on the road expecting the speeds to be about the same as my '29 Phaeton but it seems to rev its tights off. The speedo is reading way fast when compared to the GPS too. I have seen somewhere, a method to find out what ratio is in there. As best I can recall, it involved marking a rear tyre at the bottom and the ground along side, jack up that wheel till it is just clear of the ground. take out the sparklers and turn the engine by the crank for 10 turns exactly. Have someone observe how many turns the wheel does It is usually 3 and a bit but it is that bit that is important. There was a diagram showing where the mark on the tyre ended up with the different ratios. Does anyone have that info please. I suspect mine is running a 4.11 ratio instead of the 3.78 I expected. __________________ I'm part of the only ever generation with an analogue childhood and a digital adulthood.