AIR PUMP OR NO PUMP
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AIR PUMP OR NO PUMP
I have a 91 f150 efi an doing a new engine an i wanted to know if i should keep the airpump or get rid of it. some say u get better mpg an some say u dont, so wich one is it? thanks guys
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Removing the catalytic converter on the efi 300 wont affect the ecm or fuel ratio enough to have negative effects. With that said, theres no real reason to remove them.
Removing the air pump will not improve your power or mpg significantly in any way.
Removing or modifying any aspect of the emissions system will not net any gain in power or mpg (with the exception of using a catalytic convert(s) capable of improved flow), and if done incorrectly will result in poor mpg, so my two cents leave it alone, been there, done that.
Removing the air pump will not improve your power or mpg significantly in any way.
Removing or modifying any aspect of the emissions system will not net any gain in power or mpg (with the exception of using a catalytic convert(s) capable of improved flow), and if done incorrectly will result in poor mpg, so my two cents leave it alone, been there, done that.
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The guy that owned my truck before me removed the cats and he also broke the vaccum lines that went to the a.i.r emissions stuff so they were plugged. I removed the pump and it runs fine without it. I'm pretty sure it has to free up some power because its less stuff the motor has to turn. I'm sure your not going to notice a big gain...
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Post Fiend
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From: Lost
Air pump can't rob much power, since the early trucks used a real narrow belt to drive the air pump. Like 1/4"-5/16" wide v-belt.
The pump is still bolted in place on my truck, but has not had that rubber band on it the whole time I've owned it. Pretty pointless to put a belt on it, when the check valve is broken, and the port in the manifold is plugged......
The pump is still bolted in place on my truck, but has not had that rubber band on it the whole time I've owned it. Pretty pointless to put a belt on it, when the check valve is broken, and the port in the manifold is plugged......
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It sounds like it's safe to assume you don't have to deal with the smog BS where you're at so I'd say scrap it. Sure it's not enough power robbed to be noticeable, but why waste power at all?
I haven't experimented with a Ford on this, but on a Pontiac my Dad had we'd check the mileage with and without the belt on the air pump. It'd gain 1mpg whenever we'd pull the belt.
FWIW anyway.
I haven't experimented with a Ford on this, but on a Pontiac my Dad had we'd check the mileage with and without the belt on the air pump. It'd gain 1mpg whenever we'd pull the belt.
FWIW anyway.
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There have been tests on higher hp engines than the 4.9 could ever think of producing, and the net result was negligible hp gain.
I can tell you right now, you wont gain any mpg by removing the air pump or emissions equipment from a 4.9 efi. It seems like a good idea till you actually do it and ask yourself, why the hell did I waste my time? Ask me how I know.
My previous statement wasnt totally correct. If you have a 96 mass air truck with the extra O2 sensor, then you would affect the engine by removing the second cat, as the additional O2 sensor needs to see X air/fuel ratio, which can be overcome by an inexpensive device attached to the O2 pigtail, which in return sends a certain Volt signal to the ecm. But on the 95 and earlier speed density, the ecm has no idea if the catalytic converter is there or not.
I can tell you right now, you wont gain any mpg by removing the air pump or emissions equipment from a 4.9 efi. It seems like a good idea till you actually do it and ask yourself, why the hell did I waste my time? Ask me how I know.
My previous statement wasnt totally correct. If you have a 96 mass air truck with the extra O2 sensor, then you would affect the engine by removing the second cat, as the additional O2 sensor needs to see X air/fuel ratio, which can be overcome by an inexpensive device attached to the O2 pigtail, which in return sends a certain Volt signal to the ecm. But on the 95 and earlier speed density, the ecm has no idea if the catalytic converter is there or not.
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You might not gain horsepower but youd still be "cleaning up the engine" as I say. These engines have so mcuh stuff all over the place Ive been eliminating things so it makes looking under the hood a little bit more injoyable.
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mean green 91
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