Fuel System = bad MPG ?
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
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From: Shreveport/Bossier Louisiana
St. Jude Donor '08
Fuel System = bad MPG ?
Hey guys, there wil most likely be more people with my kind of motor in here than the tech section so I need your opinions.
The motor/car setup is in my sig below and the fuel system is a LPE fuel pump, Racetronix harness, and a KB BAP. The BAP only comes on when I turn the switch on, therefor I think it can be take out of the equation. I also have RC 550cc injectors.
Before my motor swap this past summer I was getting ~18-19 MPG in the city, then after my motor swap (which is the same ci as before), I am getting 14 MPG tops. Usually its more like 12-13.....Is something wrong here? The AFR stays right at about 14.6 while cruising also.
The motor/car setup is in my sig below and the fuel system is a LPE fuel pump, Racetronix harness, and a KB BAP. The BAP only comes on when I turn the switch on, therefor I think it can be take out of the equation. I also have RC 550cc injectors.
Before my motor swap this past summer I was getting ~18-19 MPG in the city, then after my motor swap (which is the same ci as before), I am getting 14 MPG tops. Usually its more like 12-13.....Is something wrong here? The AFR stays right at about 14.6 while cruising also.
Race Director
Joined: May 2005
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From: West Norriton PA
St. Jude Donor '08
At first I thought it might be that you added some gears and a big stall converter.
I got say it something with the tune. 14's a little rich, but not enough to cause your king of mileage problems. I would have a reputable tuner check it all out.
I got say it something with the tune. 14's a little rich, but not enough to cause your king of mileage problems. I would have a reputable tuner check it all out.
Thread Starter
Le Mans Master
Joined: Jul 2005
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From: Shreveport/Bossier Louisiana
St. Jude Donor '08
Le Mans Master
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FWIW- When I built mine last year I also got terrible MPGs like you. The guys at ECS spent the day guessing at what it could be. They ended up agreeing that the cam (LPE) was probably not as advertised. I swapped it out for their famous blower cam (and switched from a Vortech to their Paxton- but that shouldn't matter) and it now gets almost the same mileage as when it was stock.
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
Likes: 3
From: Shreveport/Bossier Louisiana
St. Jude Donor '08
FWIW- When I built mine last year I also got terrible MPGs like you. The guys at ECS spent the day guessing at what it could be. They ended up agreeing that the cam (LPE) was probably not as advertised. I swapped it out for their famous blower cam (and switched from a Vortech to their Paxton- but that shouldn't matter) and it now gets almost the same mileage as when it was stock.
Are you saying that they are to big Noumin? I need them that big because I am running a dry shot also so I want to have injector to handle it ya know.
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
What is the duty cycle on them in NA mode and while spraying? What plugs are you using? Standalone fuel cell for spray? I am almost thinking you may have to upgrade your fuel system to a return line style and a regulator.
Thread Starter
Le Mans Master
Joined: Jul 2005
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From: Shreveport/Bossier Louisiana
St. Jude Donor '08
Yeah, You may be right
Race Director
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
I would DEFINATELY let somone knowledgable in the field check your tune out. Remember what happened with your last setup and bad tune? 
I am more leaning towards the tune but fuel system maybe something that you want to look into.
I am more leaning towards the tune but fuel system maybe something that you want to look into.
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
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From: Shreveport/Bossier Louisiana
St. Jude Donor '08
Yeah your right bud.
That was a sad day but all smiles now 
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St. Jude Donor '05-'06-'07-'08-'09-'10-'11-'12
Thread Starter
Le Mans Master
Joined: Jul 2005
Posts: 7,121
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From: Shreveport/Bossier Louisiana
St. Jude Donor '08
No dont say it LOLIve sprayed the wet hit and it pulls really nicely
