Fuel Mileage question
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
Fuel Mileage question
Hey guys. I just filled up my tank and calculated that I'm getting about 9mpg. I got on it a bit, but this still seems a tad low. I do drive in stop and go traffic too.
What kind of mileage are you guys getting? Even on the highway I can't do any better than 15mpg and that's not getting into boost at all.
My combo is 383/vortech/auto.
Any input is appreciated. I do have experience with supercharged cars, and in the past I have broke 20mpg on the highway.
Is it my auto trans that's giving away my mileage? My stall converter is just slightly higher than stock(maybe a few hundred rpm).
What kind of mileage are you guys getting? Even on the highway I can't do any better than 15mpg and that's not getting into boost at all.
My combo is 383/vortech/auto.
Any input is appreciated. I do have experience with supercharged cars, and in the past I have broke 20mpg on the highway.
Is it my auto trans that's giving away my mileage? My stall converter is just slightly higher than stock(maybe a few hundred rpm).
Race Director
Joined: Feb 2002
Posts: 11,268
Likes: 14
From: Honolulu, HI
Is your car completely stock other than the s/c?
If so, That's crazy! If you're not seeing boost then your factory rated MPG should apply. If you're getting on it then yes you will see low MPG. Try driving around on a tank without nailing the gas to see what you get......I betcha can't
:
If so, That's crazy! If you're not seeing boost then your factory rated MPG should apply. If you're getting on it then yes you will see low MPG. Try driving around on a tank without nailing the gas to see what you get......I betcha can't
:
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
it's got a 383 with cnc ported lt1 heads and a cam. I'm not sure of the specs on the cam however...
It has 38 lb injectors and a fmu which probably isn't helping things.
It has 38 lb injectors and a fmu which probably isn't helping things.
Drifting
Joined: Dec 2001
Posts: 1,313
Likes: 1
From: providence ut
if you have the stock ecu and chip it thinks your injectors are 19 or 24 lbs and you are running rich......what ever ecu your running its rich at that mpg...........the ecu can only compensate so much to bring you to 14.7 air/fuel...what ecu .......computer and chip are you running?
Thread Starter
Melting Slicks
Joined: Jul 2004
Posts: 3,277
Likes: 32
From: Mission Viejo California
It does have an aftermarket ecm in it from what I understand.
It has 38 lb injectors and the fmu. I need to ditch the fmu because there's no way I'll run out of fuel with those injectors. I'll run out of output from the t-rex pump first.
I'm going to be looking for a good shop somewhere in CA to work on the car.
It has 38 lb injectors and the fmu. I need to ditch the fmu because there's no way I'll run out of fuel with those injectors. I'll run out of output from the t-rex pump first.
I'm going to be looking for a good shop somewhere in CA to work on the car.
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