MPG
 

I am tring to increase the MPG on my truck. I have a mild 350 in it, with a 204/214 cam, flattop pistons, Edelbrock Performer intake, HEI, headers, and a Edelbrock 1406 carb. This summer i got 13.1 MPG around town. It dropped to 12.25 during December-January, with my Qjet still on it both times. Anyway, i went ahead and bought a Edelbrock 1406 for it and put it on. Out of the box, it ran OK, but it was a little lean under light acceleration. So, i bought a calibration kit for it. I stepped it up a little in the "power" mode, and only changed the metering rods, to a #1456 rod (.073x.047). I kept the stock metering rod springs in it. My power increased ALOT, but my gas mileage dropped to 11.6. Should i try to put the stock metering rods back in, and add heavier springs instead?

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Lucas

"Another proud owner of one of the coolest trucks ever built"

drop_shift@hotmail.com

My Daily-Driver: '72 Chevy LWB Custom/10. Rebuilt 350, 300 HP thanks to a few go-fast goodies. Ochre with a white top. Future plans include TBI fuel injection, a 700R4 tranny, and possibly some 3.73 rear gears.

ttt

Go for an overdrive trans if you want to see decent gas mileage. Mine was set up much as yours with a 350 turbo and 3:73 gears and the mileage was 13ish at best. I swapped in a 700R4 and it went to 19-20 at 55 mph, 17-19 at 65 mph.

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1971 C10 swb stepside 350/700R4/3.73posi
Killingworth, Connecticut

If you are really doin for milage,put a vacumn gage on your dash,& try to keep it in the green zone when cruising.......nice tuning tool too.......69 longhorn.

Well...i may go ahead and try the spring thing...only takes about 5 minutes on my carb. I have also heard of welding a bung in the exhaust behind the headers/manifolds, and putting a cheap O2 sensor in it, hooking up a mulitmeter and measuring what it puts out to see if the engine is running rich of lean. Is this a good idea, and how would i go about doing it? Oh, i have plans for a 700R4, but i am lacking the $$$$ right now..

Every truck ive ever had small or big block always got around 10 period.

I dont think your milage is too far off,& i dont have any high tec equipment to check em with......if it burns my eyes ,its too rich. how are you set on timing? ported or manifold on the vac advance?

The truck hasn't been timed in a while...it was 12 degrees advance i THINK...(can't remember). I may get it timed this week just in case. As the vaccum advance goes, it is hooked up to the full time vaccum port on the driver's side of the carb.

that sounds about right to me for the combo. You might play a little ,& see if you can optimize. The vac guage will tell you a lot about tuning......i have run 1 in the longhorn forever.........69

[This message has been edited by 69 longhorn (edited April 06, 2002).]

Port it for better fuel mileage.

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1971 C10 swb stepside 350/700R4/3.73posi
Killingworth, Connecticut

About how much is a halfway decent vaccum guage? I would like to find one about the right size to mount in the blank part of my insturment cluster, next to the oil pressure guage...

Dont know......ported has worked good for me on the leaner setups with stock cam,but i have had better luck on perf set ups on manifold vac.....69

About $40 on an auto meter......2 1/16"

the other fun thing about the vacume gauge is that when you stomp on it it goes into red and reads power. Hehe that where mine would always read. hehehe

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71 SWB Stepside, was a 250, now is a 402 Big Block with 4 speed and 3.73's

72 LWB 4x4 350 4-speed 3.08's posi wearing army olive drab green (SOLD!)

68 BURB 50TH LOOKALIKE with built 350 4-speed 4.11's and posi

Be Happy w/ the Mileage you are getting now untill you get a OD Tranny.. But untill then do not complain because, hell if my 68 could get a 13 mpg, then that would be an improvement over mine about 8 - 10 on freeway and 4 - 6 in town and I have to run nothing less then 91 Octane, or my engine runs horrible!! I am definitley thinking of getting an OD Tranny as soon as I get the cash up and do my frame swap and finish body work up !!

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Truck #1 68 Chev LWB Fleet w/ Wood Floor (Sucks Gas and Hauls Ass!) and in process of Body Work...

Truck #2 1994 GMC Sierra SL w/ 4.3L Vortec V6, 4L60E Auto!!