Guess what saw is coming back for it's 4th or 5th "Encore"?

[MustangMike]

In the mid 70s my 427 Mustang (a 70 Boss 302 body) with 3:50 gears and a 4 speed got 14 MPG on the highway and everyone was impressed. None of my friends hot rods at the time got anything close to that … but most of them had gears.

Of course averaging 80-90 MPH likely didn't help the gas mileage.

I'd guess you were going a bit slower, maybe had a 5 or 6 speed tranny, and likely a more stingy carb or injection.

I was running an 850 Holly Double Pumper … it got it done!

 

[Stevetheboatguy]

My not stock 1968 396 Camaro and got 18 mpg combined city/highway and I had a 1965 400 HP 409 Impalla that got 20 mpg on the highway. I had a 396 Nova that also got a bit better than 20 mpg on the highway. The only single digit fuel milage big block I had was an LS6. 4 mpg, in a Nova. If those old sloppy cammed big block cars had modern closed loop fuel systems and auto timing adjustments, they'd be well over 30 mpg. The main thing that made those big blocks work was the higher fuel quality of the day. I remember a blown 4:71 small block Nova and blown 4:71 small block 23T bucket roadster that both got 18 mpg. The roadster ran 9's the Nova 10's. That was the early 80's.

Today's factory hotrods are simply amazing. Factory 9 second Demons, 9 & 10 second electric luxury sedans , as well as 5 & 6 second street cars with turbo 615 inch big blocks getting 11 mpg and driving over 1000 miles to the tracks while pulling a trailer no less. But today you can just buy horsepower, back then you had to build it. It was a time when most speed secrets had to be discovered, now they are pretty much known.

Must be a big difference between big block cars and trucks. I was always happy with 10mpg. Owned several including a 86 q jet 454, 87 tbi 454, 95 tbi 454, built 454 h.o 850 eddy, square port Siamese 502 bow tie holly dbl pump pos, and last was a '03 8.1 w a Allison. Every damn one got 10mpg no better no worse.

Heck even my old 94 35ft Winnebago chieftain w a tbi 454 got 10mpg.

I'm not complaing about it one bit. I'm just baffled someone has gotten better than 10mpg. And I may be lying that 502 was probably closer to 9mpg it was a pig.



Steven

 

[SpaceBus]

Must be a big difference between big block cars and trucks. I was always happy with 10mpg. Owned several including a 86 q jet 454, 87 tbi 454, 95 tbi 454, built 454 h.o 850 eddy, square port Siamese 502 bow tie holly dbl pump pos, and last was a '03 8.1 w a Allison. Every damn one got 10mpg no better no worse.

Heck even my old 94 35ft Winnebago chieftain w a tbi 454 got 10mpg.

I'm not complaing about it one bit. I'm just baffled someone has gotten better than 10mpg. And I may be lying that 502 was probably closer to 9mpg it was a pig.



Steven

My 03 Coachmen 36' Ford v10 bus is probably around 6-8 mpg. A diesel bus would be even larger and get about the same.

 

[sawfun]

Must be a big difference between big block cars and trucks. I was always happy with 10mpg. Owned several including a 86 q jet 454, 87 tbi 454, 95 tbi 454, built 454 h.o 850 eddy, square port Siamese 502 bow tie holly dbl pump pos, and last was a '03 8.1 w a Allison. Every damn one got 10mpg no better no worse.

Heck even my old 94 35ft Winnebago chieftain w a tbi 454 got 10mpg.

I'm not complaing about it one bit. I'm just baffled someone has gotten better than 10mpg. And I may be lying that 502 was probably closer to 9mpg it was a pig.



Steven

Low static compression big blocks pretty much suck. Trucks tended to be low compression. My stock 76 crew cab dually with 454 4 speed got 8 mpg. On good gas with 10:1 or better compression you gain, not only snap, but a good deal more efficiency. I had read that wider bore cylinders are considered dirtier (the reason behind going to the 10 cylinders) as there is more unburned fuel at the edges, away from the spark. I'm guessing the higher static compression lead to more fuel being burned. The problem was the low compression, as well as not having todays electronic monitors and controls. Camshaft technology as far as numbers are likely a factor as well.

 

[sawfun]

My 03 Coachmen 36' Ford v10 bus is probably around 6-8 mpg. A diesel bus would be even larger and get about the same.

Diesel engines are more efficient so milage should be better. Our 40k lbs city busses get 4 - 5 mpg. My 13k lbs deuce and a half gets 11 - 13 mpg. And my 6400 lbs Dodge bt6 5 speed gets 20 - 30 mpg. Gas engines would not get anywhere near those numbers. My 95 Dodge v10 auto dually got 14 mpg. It actually got worse as it broke in and was a gutless dog for an 8 lier engine. By buddies Ford v10 got 8 mpg in his 06 F350 but had way more power than my old Dodge v10. The Ford v10 has ti run very high, for a truck, rpm to make its power. That is likely the reason for the poor mpg.

 

[SpaceBus]

Diesel engines are more efficient so milage should be better. Our 40k lbs city busses get 4 - 5 mpg. My 13k lbs deuce and a half gets 11 - 13 mpg. And my 6400 lbs Dodge bt6 5 speed gets 20 - 30 mpg. Gas engines would not get anywhere near those numbers. My 95 Dodge v10 auto dually got 14 mpg. It actually got worse as it broke in and was a gutless dog for an 8 lier engine. By buddies Ford v10 got 8 mpg in his 06 F350 but had way more power than my old Dodge v10. The Ford v10 has ti run very high, for a truck, rpm to make its power. That is likely the reason for the poor mpg.

My 06 Ram 3500 four door dually long bed six speed cummins averages 25 MPG on country roads. A fully loaded diesel bus RV usually does a bit better than fully loaded gas bus RV, but the diesel bus is just larger and can tow more. Plus the engine at the back is nice. To e fair I haven't driven my bus fully loaded, but it sucked driving it home empty! I don't know about the Semi truck based diesel RVs, those are a different beast.

 

[kingOFgEEEks]

Low static compression big blocks pretty much suck. Trucks tended to be low compression. My stock 76 crew cab dually with 454 4 speed got 8 mpg. On good gas with 10:1 or better compression you gain, not only snap, but a good deal more efficiency. I had read that wider bore cylinders are considered dirtier (the reason behind going to the 10 cylinders) as there is more unburned fuel at the edges, away from the spark. I'm guessing the higher static compression lead to more fuel being burned. The problem was the low compression, as well as not having todays electronic monitors and controls. Camshaft technology as far as numbers are likely a factor as well.

Also just a thought - the Rochester Q-jet was a great carb for power and efficiency when tuned right - the small primaries for economical cruising, and big secondaries for powah! Keep your foot out of the skinny pedal, you can get some decent mileage.

 

[MustangMike]

Yea, but nothing made your car respond and run like a fuel sucking double pumper Holley!!!

 

[sawfun]

Actuall

Yea, but nothing made your car respond and run like a fuel sucking double pumper Holley!!!

Actually, a spread bore double pumper can be tuned for milage pretty easy. I like them better than the Qjet even though they test dirtier thsn the Qjet. My 800 spread bore won't pass emissions nor will my Qjet, but my Edelbrock AFB will, even though the other two carbs get 2 - 3 mpg better milage. I haven't figure that one out yet.

 

[SpaceBus]

More fuel efficient ins't necessarily cleaner burning.

 

[sixonetonoffun]

Yea, but nothing made your car respond and run like a fuel sucking double pumper Holley!!!

Until you hit a bump.

 

[SpaceBus]

Until you hit a bump.

What makes you say that? I've seen many dirt track racers use Holley.

 

[sixonetonoffun]

What makes you say that? I've seen many dirt track racers use Holley.

The dual bowl float setup. Having to add slosh tubes to the jets to keep em from sucking air. All manageable as long as ya know WTF your doing.

 

[ZERO]

Bob, with all the fires on the West Coast, could this have to do anything with the 1st gen of ATs that had problems running correctly in smoky weather?

I remember the discussions here early on, has that been fixed with the 2nd gen of ATs in the MK2s and the 572s?

I can see how the first line responders don't want to be beta testers in life or death situations.

Those are huge mass volume contracts and no company want to lose out, makes perfect financial sense.

 

[andyshine77]

I believe the 576 had first generation AT the 550 and 562 had second generation and the 572 and 550 mk-II has third generation AT.

 

[huskyboy]

560 mk-II has third generation AT.

You mean the 550mk2?

 

[Spike60]

Bob, with all the fires on the West Coast, could this have to do anything with the 1st gen of ATs that had problems running correctly in smoky weather?

I remember the discussions here early on, has that been fixed with the 2nd gen of ATs in the MK2s and the 572s?

I can see how the first line responders don't want to be beta testers in life or death situations.

Those are huge mass volume contracts and no company want to lose out, makes perfect financial sense.

I really can't answer that, cause the firefighting deal never came up in discussion over on this side. But there were some early issues with 550's idling in the bucket when guys were doing treework. It would start to digest it's own exhaust and affect the fuel settings. Wouldn't affect the top end but would stumble off idle. The new saws seems to hold all of their settings much better in all conditions now.

 

[andyshine77]

You mean the 550mk2?

That's what I was going for.[emoji17]

 

[dustinwilt68]

Glad we have lots of options out there to choose from, 1 saw may not be the best for all jobs even if they are similar in size.

 

[ayoungtexan]

Stihl guys in the Husky thread again. Like ants at a picnic.

A 372 can turn a Stihl guy into a Husky guy in the blink of an eye