poor mileage

[Todd....!!]

Hi Charles,

Thanks for the insight n stories and all...

I don't believe that gears and cam have anything to do with each other
if we're not talkin about racing... 

And from what I've heard and read, carb cfm should be chosen based on a
30% increase as to what is theoretically calculated as to what is
perfect... so a 750 may be a bit small, I shift at 6,000, haven't gotten
my launch down yet, the tires don't stick if I power brake it even a
little bit, so as soon as I get tires, I'l see which launch technique
works best...

If you BLOWN 440 gets better gas mileage than my NA 440 then somethins
GOT to be set wrong or I just can't keep my foot out if it long enough
to be able to tell what me best mpg is!  Will try to be more disciplined
in the future!

Thanks again!

LATER!

Todd....!!
http://www.c-com.net/~atc347/toddlnk.htm

Charles wrote:
> 
> On Wed, 12 May 1999 17:14:19 -0400, you wrote:
> 
> >>I get 6.1-6.2 mpg on the highway currently and MUST correct this
> >>I believe I CAN get over 20 mph with a mild 440 in a 3700 lb car!
> 
>         Uh, that's "mpg", right?  ^^^   ;)
> 
> >First off, if you are still running a 8 3/4 rear end, get a high ratio center
> >section ( 2.76 or so) and swap it
> 
>         May be a little tall depending on his cam... how 'bout
> 3.23?
> 
> >Next, find a 650 or smaller _vacuume_ secondary carb
> >Third, run a distrubitor with vacuume advance on the street.
> 
>         Excellent advice. Too many hotrodders think "bigger is
> better" when it comes to induction systems. Same for
> mechanical-only distributors "it's a RACE part, so it must
> be really fast"!
> 
> >Fourth,  keep your foot out of it!
> 
>         Come on, Harold. The whole point of a 440 IS to put
> your foot in it!
> 
> >You may not get 20 mpg, but you should at least double your current 6 mpg.
> 
>         I concur. I used to have a Valiant (~3200 lb) with a
> 383, Holley 750 vac.sec, vacuum advance distrib, Street Hemi
> cam, headers, 4-speed manual, 3.23 rear.
> 
>         Got 14-15 mpg on the highway at 65 mph. Mix of highway
> and Saturday night stoplight action, 12 mpg. Lowest ever was
> 8.5 mpg (nearly all at WOT going to the 7-11 store a quarter
> of a mile away ;)
> 
>         Then I got carried away and built a 7:1 440, BDS 6-71
> blower, two 750's, no vacuum advance. Only 9 mpg on the
> highway with the same drivetrain. Of course it was flooding
> badly (dirt in the needle valve seats)...
> 
>         One more non-EFI story. My '84 F150 was only getting 12
> mpg until I advanced the timing about 20 degrees (damper
> mark had moved, apparently, so it was way too retarded). Now
> 15 mpg with no other changes. Points out the value of a
> proper advance (i.e. including vacuum advance), doesn't it!
> 
> -Charles