Time to go, but how?

drolston said:
One thing that gives me confidence that I can live with the 3.25 rear is my wife's '34 pickup. It has a C-4 automatic and 3.00 Ford 9" rear end, and has never lugged or downshifted on the hills that pass for mountains in this part of the country.
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An automatic has a torque converter (as in torque multiplier), automatics always have higher gears because of this (as well as converter slippage at higher rpms).
 
Old Henry
You be correct. I guess I always get mixed up with the aircraft carbs but they don't have a choke. They have a mixture control that leans the fuel input to the carb. A person could lean the Model A & B carbs but that is no help on a V8. Most aircraft can be leaned by pulling the mixture control for higher altitude just as long as you don't pull it too far. They also use different power valve settings on some cars for different altitudes. If it has Holley type carb a person can use a small window type power valve for higher altitudes.
 
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The fuel for the power valve is controlled by a fixed power valve channel restriction. The power valve itself has no control over the volume of fuel supplied when it is opened.
 
JSeery said:
An automatic has a torque converter (as in torque multiplier), automatics always have higher gears because of this (as well as converter slippage at higher rpms).
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Good point. The torque converter is a big factor in effective gearing for getting going from stopped. However, at speed in third gear, the C4 is essentially direct drive, like the standard transmission in high. And in that mode the performance of the '34 suggests enough torque to handle the big hills without the need to downshift.

So, I will try the 3.25 gears. If it turns out that low isn't low enough, I can go to a 29 tooth cluster gear.

And I will stay with the .045 jets in the 97 carbs, which work well at low altitude. If it runs too rich through the high passes, it should do no harm, except to my wallet.
 
Craig with "Old Henry".... On the freeways I stay in the right lane under 65 mph. I'm usually there with some 18 wheelers, motorhomes, or trailers and am just fine.

I agree with you.. I try to follow the law, i.e "slower traffic keep right".. The only problem with that.. besides the big trucks, RVs, etc.. is these lanes get so much traffic in CA that they tend to be in the worst condition.. potholes, broken/sunken concrete, just terrible at times!
 
Vintage Copper 47 said:
Craig with "Old Henry".... On the freeways I stay in the right lane under 65 mph. I'm usually there with some 18 wheelers, motorhomes, or trailers and am just fine.

I agree with you.. I try to follow the law, i.e "slower traffic keep right".. The only problem with that.. besides the big trucks, RVs, etc.. is these lanes get so much traffic in CA that they tend to be in the worst condition.. potholes, broken/sunken concrete, just terrible at times!
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Not to mention the "ruts" in the right lane from the big trucks that reek such havoc with my bias-ply tires and make them do "The Bias-ply Boogie".
 
flatjack9 said:
The fuel for the power valve is controlled by a fixed power valve channel restriction. The power valve itself has no control over the volume of fuel supplied when it is opened.
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The power valve would have to be changed out to affect a change to the mix. The circuit channels are a fixed size but they will generally allow for variations in flow even with a fixed amount of flow. Even the older carbs were made to be used on different size engines with different needs. The older carbs don't have a lot of choices of different power valves for this purpose though. For later carbs, it's a different story and that's what I was referring to. Any fuel flow change will change the mixture. They made small window power valves for higher altitude operation that reduce the amount of fuel flow under power. The channel can be fixed but the control is still in the feed valving. Less feed equals less flow and leaner mixture but it's only under power. An aircraft carburetor has fixed sized circuit channels too but the jet size is for max flow so there is some adjustability for different size engines. The mixture control meters the amount of flow that gets into the circuit by opening up more or closing more through a series if tiny little ports in the valve disk or opening & closing a needle jet like the Model As & Bs did.
 
Trying to maintain Interstate speed (60+) while climbing to mountain passes at high elevation will surely get the throttle open far enough to open the power valve on the primary 97. Would it make sense to disconnect the accelerator pump linkage that day to lean out the mixture at high throttle position? Just thinkin!
 
The accelerator only pumps when you push down rapidly. Once you stop pushing, it's no longer pumping. If it would run off one carb then you could just disconnect one of them but I don't think you would have any real problem unless you were trying to climb Pike's peak or something of that nature. Performance will not be the same but it shouldn't try to quit on you or anything that severe. On the aircraft, we seldom have to start leaning the mixture until the altitude is over 8000 ft above sea level. The air starts getting really thin above 12,500 ft. Those mountain passes can get up there as high as 10,000 ft give or take but not on all of them.
 
If you take the scenic route across Nevada, Highway 50 instead of I 80, you will cross 17 mountain passes, many going above 7000 feet, many at an 8% grade and curves down to 35 mph. It is certainly my preferred route.well worth the fun driving challenge. Not an interstate ride for sure.steepest grades on I 70 don't go above 6%.that grade hardly slows down my totally stock set up.
 
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Old Henry said:
If you take the scenic route across Nevada, Highway 50 instead of I 80, you will cross 17 mountain passes, many going above 7000 feet, many at an 8% grade and curves down to 35 mph. It is certainly my preferred route.well worth the fun driving challenge. Not an interstate ride for sure.steepest grades on I 70 don't go above 6%.that grade hardly slows down my totally stock set up.
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Yes sir that 50 route across Nevada has some grades. The only time my Freightliner gave an over heat warning. ( hauling a load of glass ) Definitely worth the trip. Particularly since it leads right to Carson City.

It took many years, but I wish everyone could see this country as I have.:)
 
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