Gas Mileage High HP

svtcobratenthan

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I was not trying to be a dick. I was just saying my 2 cents. I get people ask me all the time whats the mpg. I say the same thing if that is a issue that is not the car for you.
 

MalcolmV8

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Yes, I'm actually pretty happy considering E85 commands at least 35% more fuel wot than gasoline. You averaging 11mpg on gas is eye popping....you been a bad boy! Lol. Mine kind of driving style.

Also, possibly like you said....that bigger 2.9 has more parasitic loss, even over a 2.3.

I know with the blowers on the work bench turning over the 2.9s was MUCH harder by hand. My Eaton I could spin with two fingers the 2.9 I had grab firmly and muscle around to spin. So the engine's definitely going to feel that.
Although my 11 comes from the right foot more than anything.

photo.JPG
 

svtcobratenthan

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Well being as u asked it costs $9.11 a gallon it lasts about 3 hrs the way i drive it. Like i said i drive it to have fun. Thats about 130$ a tank.
 

c6zhombre

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I know with the blowers on the work bench turning over the 2.9s was MUCH harder by hand. My Eaton I could spin with two fingers the 2.9 I had grab firmly and muscle around to spin. So the engine's definitely going to feel that.
Although my 11 comes from the right foot more than anything.

photo.JPG



Wow, really interesting, Malcolm. That's some good info there. I'll tell you when I swapped to the "high hp" carbon coupler earlier this year, I obviously was messing with the snout. I still remember spinning the pulley by hand and it was relatively easy.

One more note on the tune...Kevin told me the 22psi E85 commands as much fuel wot at 3000rpms than the 17psi 93 tune does at any point across the rev band :burnout:
 

MalcolmV8

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One more note on the tune...Kevin told me the 22psi E85 commands as much fuel wot at 3000rpms than the 17psi 93 tune does at any point across the rev band :burnout:

That I can believe. I haven't tuned my Cobra on E85 yet but I tuned the turbo Honda on both 91 and E85 and I couldn't believe how much fuel it sucked up on E85 lol. Gas mileage went to hell but good grief the power increase was awesome. Mostly because I could turn up the timing and boost :)
 

svtshadow

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if you post a thread about it, you're worried about it. You bought/drive a supercharged v8. Out of boost my car probably does 18-20mpg

In boost I probably get 10.

buddy's KB car gets about the same.

To get horsepower you need fuel, simple as that. Higher horsepower requires bigger injectors = more fuel consumption.

Take a chill pill, OP is not worried about gas mileage.:nonono:
 

lilcoop03

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i undertand the o.p.'s original curious thoughts about mpg's..however.. its like a lot of you other guys said. more power requires more fuel. period. our dohc 4.6's make the best of it for sure but you should not own one of these and consider mpg's part of the equation. thats why my dsg kb car stays in the gargage most of the time and i daily drive a ranger. i recently did the kb on my car and 60's etc... def not something you wanna have to drive every day and put fuel in
 

MalcolmV8

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Seems like a legitimate question to me. If a guy has a ported Eaton car now and daily drives it quite a bit in the summer and enjoys the car it's a good thing to consider. You're going to loose over 5 mpg and if that doesn't sound appealing he may just want to keep it a ported Eaton car. Not everyone uses these as weekend race track toys and nothing else.
 

nextime

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Thanks all who posted the useful info I really appreciated the honesty.

To the couple dicks out there if I wanted good MPG I would have kept my 2011 Edge or my 2001 Vette that did get 30MPG on the freeway, and yes this is a fact and I didn't believe it myself till I bought a C5 and experienced it!
 

SlowSVT

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I know with the blowers on the work bench turning over the 2.9s was MUCH harder by hand. My Eaton I could spin with two fingers the 2.9 I had grab firmly and muscle around to spin. So the engine's definitely going to feel that.
Although my 11 comes from the right foot more than anything.

photo.JPG

Looks like someone's thinking 4 stage supercharging

Think about what the crank snout has to endure turning that mass while being rapidly accelerated and decelerated trying to keep up with the tachometer. The inertia of a 4.0 can't be pretty :uh oh:
 

MalcolmV8

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Looks like someone's thinking 4 stage supercharging

Think about what the crank snout has to endure turning that mass while being rapidly accelerated and decelerated trying to keep up with the tachometer. The inertia of a 4.0 can't be pretty :uh oh:

Yes a lot more which is part of the reason I refuse to loose the stock lower with the cage. Also when I had my block apart in 09 I had the snout of the crank double key'd which I thought would help. However I've since read conflict when researching the topic and not sure which is true.
So some guys say the key is important and that's why you double key. Others I read say the key is nothing more than to align the pulley during install and it's the press fit that keeps it in place. If that's true then when I double keyed my crank all I did was remove surface area for the press fit. Who knows.
It's been running strong for years so I'm not worried. Just interesting food for thought. As for the pic... I should have thrown some nitrous bottles up while I was at it. Didn't think of it at the time :)
 

SlowSVT

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Yes a lot more which is part of the reason I refuse to loose the stock lower with the cage. Also when I had my block apart in 09 I had the snout of the crank double key'd which I thought would help. However I've since read conflict when researching the topic and not sure which is true.
So some guys say the key is important and that's why you double key. Others I read say the key is nothing more than to align the pulley during install and it's the press fit that keeps it in place. If that's true then when I double keyed my crank all I did was remove surface area for the press fit. Who knows.
It's been running strong for years so I'm not worried. Just interesting food for thought. As for the pic... I should have thrown some nitrous bottles up while I was at it. Didn't think of it at the time :)


A sheared keyway can do a lot of damage to but I haven't heard of any single keyway failures in a mod motor. I had a big problem with shearing the mag keyway on my Honda XR250 from "kick-back" off the kick starter which left me stranded in the woods more than once. The fix was applying Loctite retaining compound to the tapered mag shaft and it never happened again.

Retaining - Henkel
 

Rich'sTRsvt

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I got 20mpg on 93 when pullied and 18mpg with the TVS and 80lb injectors on 93. I have always seen a pretty constant fuel economy but I live 15 miles into the country if that makes a difference.
 

SlowSVT

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Torrance

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Since I went E85 and 2.6KB, I see an average of 12-13 MPG. I see 15 miles of interstate to get to the closest "big" town, where I'll cruise a car show and grab some food or something.

It's 80 miles from my house to Blankenship's shop and 50 miles to work.

Now matter where I go or what I do, I see 12-13 MPG average, around here.
 

Lobo_Loco

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Since I went E85 and 2.6KB, I see an average of 12-13 MPG.

Now matter where I go or what I do, I see 12-13 MPG average, around here.

^^^^ that is kinda where I'm at too...and with the e85 being $3.00-$3.15/gallon down here I don't think its too bad
 

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