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Discussion Starter #1
Long story short I'm trying to piece together in my mind my next motor. A year or 2 ago on HB I started a thread about 496 pump gas build. In that thread someone states that the build would be about the same price hp for hp with a blower, and I'd get better gas milage out of the blower to boot. The exact verbage is "the blower motor will still be better sans fuel consumption!" I assume sans is a typo, I dunno. Was he pulling my leg or could the terms blower motor and better milage accually go together in a sentence. Keep in mind when this came up we were talking about my altitude issue (4500 ft)
 

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I'm famous !
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Long story short I'm trying to piece together in my mind my next motor. A year or 2 ago on HB I started a thread about 496 pump gas build. In that thread someone states that the build would be about the same price hp for hp with a blower, and I'd get better gas milage out of the blower to boot. The exact verbage is "the blower motor will still be better sans fuel consumption!" I assume sans is a typo, I dunno. Was he pulling my leg or could the terms blower motor and better milage accually go together in a sentence. Keep in mind when this came up we were talking about my altitude issue (4500 ft)
a blower motor could be set up for fuel miliage - except ya never keep your foot out of it long enough to find out

I think cams will be the key factor in fuel miliage - and it would have to be an injected motor - In my opinion . i aslo think turbo's would do the same thing more effeceintly
 

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I assume sans is a typo, I dunno.
"Sans" means without, right? So, better without fuel consumption?

My blown MINI gets about 30 MPG, and even getsa up to 40 if i keep my foot out of it. Something about the efficiency of the entire machine by using the blower.
 

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Wishin I was at the lake!
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I suppose it's gonna depend on what power level you're looking for. If you need boost to make big power, then turbos are hands-down more efficient than blowers (even good ones) in terms of BSFC. If you don't need that much power, then build something with plenty of compression and only enough cam and head (moderate cam timing and port size) to support your target power level. Computerized fuel and spark management should be used to accurately control AFR and ignition advance throughout the load/RPM range. Small bore/long stroke would probably be better than big bore/short stroke for good fuel efficiency.
 

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Discussion Starter #5
I think I need a blower just because there is no air here. (4500-6500 ft.) So a 650 hp 496 n/a turns into 550hp motor. sans, that's a new one to me,I've never heard of that before I'm glad some one has.:)grn
 

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Lord of the Drinks
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All things being equal (N/A vs blower HP), I believe you will need to dump more more fuel in the blower motor (parasitic hp needed to turn the blower).

Turbos...not so much.

Are we actually talking about milage on these forums? lol....
 

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I think I need a blower just because there is no air here. (4500-6500 ft.) So a 650 hp 496 n/a turns into 550hp motor. sans, that's a new one to me,I've never heard of that before I'm glad some one has.:)grn
Sans is french for "without". Who would put a Renault in a boat anyway?
 

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Dont know if this helps but I have been finding my 434 (small bore big stroke) with an 8-71 good on fuel. I also think it has to do with my cam choice and when not under boost it is realy just a low compresion mild bbc. If you want to talk about my build just shot me a pm.
Paul
 

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Wishin I was at the lake!
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I think a really good combo for an efficient 700ish hp would be an LS1 (or similar) with forged pistons and a couple of small turbos on it. Wouldn't need to get wild on the cam or heads to get that power and would be a very light package. Finding some water cooled exhaust manifolds might be a little tough. I'm sure Hardin, CMI, or Lightning would make you a set for the right price!

:)bulb
 

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"Sans" means without, right? So, better without fuel consumption?

My blown MINI gets about 30 MPG, and even getsa up to 40 if i keep my foot out of it. Something about the efficiency of the entire machine by using the blower.

You put the blower on your Mini Cooper? I raced with a guy that had one on his 318ti. That was a kick in the pants for that litlle 4 banger. He could hang with the e30 m3's. He put it into the wall at PIR doing about 125, dang the bad luck. His RA-1's saw a little to much track time.

A blower on my 6.0. A guy I work with has a blower on his GMC 8.1.
 

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This has nothing to do with boost but I had a 640+ engine in the boat and blew it up. I put a 500+ hp engine in it to replace and that damn engine used way more fuel than the high Hp engine. It took way more throttle effort than the high hp engine and used way more fuel.

So your jet at 6,500 ft might do the same thing. How do you find warm water at that altitude ?

Sleeper CP
Big Inch Ford Lover :D
 

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Discussion Starter #13
I live at 4500 ish and most of the lakes in the mountains are higher than that. We go to flaming george(wy) quite a bit and I'm toying with the idea of just leaving boat and suburbar up there and driving my civix.I and my bros' and 1 sister have small(sererate) places up there. I haven't googled it but I'm guessing it's at least 6500 ft.
 

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Without a doubt. Here's my testimony:

'76 Hallett bubbledeck, heavy lake layup.
Original motor:
461 Olds, 10:1, 350 hp?, single 750 carb, Berk JC aluminum A, loose setup.
Max rpm 5000

With the heavy boat, it would take a lot of throttle to keep it moving at cruising speed, which was 3300 rpm or 30 mph give or take. To cruise at that speed, the secondaries were partially opened. I could blow thru 20 gallons I
in an hour if I wanted to. But a typical day was good for about 25 miles and top speed of 60.

Chevy motor:
full roller 468, 8.5:1, twin 850dp, 871, 11 pounds, max rpm 6300, blueprinted race pump, stainless A.
Cruising speed 4000 rpm, throttle barely cracked. And when I want, I have enough hp to rock that bitch up to 90mph. But in a normal day, I can go 45 miles on that same 20 gallons and be able to play, even with the added weight.
Lower compression motor works less, requires less fuel, more efficient.
 

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Discussion Starter #15
Thanks guys, I just thought it sounded wierd a blower getting better milage. With my 21 I went through 10 gal of gas the other day so fast it was unbeliveable. I just don't have the hp to get it on top of the water. I'd be suprised if I didn't get better milage with a bigger hp motor.
 
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