1970's "30mpg" V8 cams, big car, w/14:1 CR on 87oct

[thomason2wheels]

Originally Posted by War_Wagon

I'd be interested to see the rear axle ratio used in the '32 Ford. I didn't see it listed, and put that together with a lack of information on the circumstances of their mileage "testing" leaves a lot of room for massaging the numbers. If they just drove around the city and the suburbs, then a set of gears like 4:88s would let the car move out and get to speed with very little throttle. Granted it would be limited to "in town" speeds before you had to go from barely taxing the engine to revving the crap out of it to go any faster, and while heavy by todays small car standards, a 32 Ford with a SBC would probably weigh in at what, just over 3000 pounds? Yes it's full frame, but its a small frame, and it's not like the car is full of airbags, ABS equipment, sound deadener, side impact beams etc etc. Being a hot rod, it probably had some sort of lightweight aftermarket wheels, and even narrow "pizza cutter" tires and wheels on the front. That's cutting a lot of rotational mass and rolling resistance. And at low speeds, the aero wouldn't really come into play as much.

If most of the testing was on the highway, then a gearset in the opposite direction, say 2:76s, would have similar results. It would be a gutless dog in town, but it would literally idle down the highway once it got moving. The "Mileage Maker" camshaft would probably just mellow out the engine enough so it could live with not having a lot of throttle. Team that up with a low-rise intake manifold designed for low RPM torque, and a small 4 barrel carb and it might work.

Being a 32 Ford, maybe the rear axle had been replaced with a 2 speed model, ala Bonniville salt flat racer style. Another way to make the test look good. Regardless of all this, I would love to see that original article as well, I hope someone can source it!

Whay u are saying is correct. I had a friend that had a full size dodge van with the 440ci v8. He put a holley spreadbore carb with small primaries, an edelbrock sp2p rv intake, a set of small tube headers and dual exhaust and an rv cam to go with the 3.08 rear end and he could get 18 mpg at interstate speeds. Plus it was wickedly quick to 90 mph. Power withefficiency...it worked well.

I did something similar withmy old 74 nova. Converted from 2 bbl single exhaust to 4 bbl dual exhaust and headers. My mileage back and forth to work went from 10 to 18, with better than 20 on the road. Well worth the time and expense considering i put almost 200 k miles on it.

[freebeard]

still searching wrote:
(does anyone remember the "6 cycle" engine described in Mother Earth News in the 1970's that almost doubled power or mileage, your choice, by having two power strokes? No? Thats why I bring up these topics. Nobody is using that either that I know of.)

Not having seen the MEN article, I thought the 6-cycle engine was intended to reduce emissions with the 2nd power stroke cleaning up any charge unburned due to reversion, etc. Without a second intake stroke, how could you get 2x anything? I'd expect 2/3 for a given displacement.

[slurp812]

Originally Posted by oil pan 4

C/R is calculated by BDC cylinder volume over TDC cylinder volume.
It doesn't take throtteling or valve timing into account.

I suppose you could call that mechanical compression ratio. As opposed to effective compression ratio.

[maxc]

Look up Larry Widmer. He's doing high CR engine pump gas with 30 mpg with carbs.

[2000neon]

Originally Posted by oil pan 4

C/R is calculated by BDC cylinder volume over TDC cylinder volume.
It doesn't take throtteling or valve timing into account.

You are correct as far as static compression ratio, but then there is also dynamic compression, which does take the other factors into consideration.

[stillsearching]

Originally Posted by freebeard

Not having seen the MEN article, I thought the 6-cycle engine was intended to reduce emissions with the 2nd power stroke cleaning up any charge unburned due to reversion, etc. Without a second intake stroke, how could you get 2x anything? I'd expect 2/3 for a given displacement.

It wasnt about emissions... the water turns to steam creating a second power stroke. The heat normally going out the exhaust is turned into pressure. I don't know if it was literally 2x the exact power, but I seem to remember the discussions saying it was pretty darn close. They figured efficiency went from like 33% up to 60% or more. Twice the power strokes on the same amount of fuel. There was some loss recompressing the mixture and such but it recovered most of the heat energy.

[freebeard]

Never mind then. I thought I'd heard of a 6-cycle engine that went intake-compression-power-compression-purge-exhaust. I didn't know about the steam, would that be on the 5th stroke?

Personally I don't think water should be allowed anywhere near an engine (it's corrosive); but if this would allow deleting the radiator, hoses, pumps and anti-freeze (which is poisonous to puppies and kittens) it might be worth it.

[oil pan 4]

Originally Posted by freebeard

Personally I don't think water should be allowed anywhere near an engine.

I run water injection on my diesel and dont have any problems.

[freebeard]

I realize I'm not typical––for a 'cager'. And I remember the Olds Jetfire.

But I thought exhaust systems rust from the inside out due to atmospheric water in the exhaust.

I see you posted in a rather interesting thread: http://ecomodder.com/forum/showthrea...tml#post272873 That Azmio guy was kind of interesting.

[stillsearching]

Originally Posted by freebeard

Never mind then. I thought I'd heard of a 6-cycle engine that went intake-compression-power-compression-purge-exhaust. I didn't know about the steam, would that be on the 5th stroke?

Personally I don't think water should be allowed anywhere near an engine (it's corrosive); but if this would allow deleting the radiator, hoses, pumps and anti-freeze (which is poisonous to puppies and kittens) it might be worth it.

Yup 5th stroke, as I think I mentioned up above.

It's possible that stainless steel exhaust and valves would be needed, and maybe a more corrosion resistant aluminum block and heads, but I don't see how that's intolerable. Iron engines would probably work fine for testing.