HELP! extremely bad MPG w/ supercharger
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Car: 1987 IROC-Z Camaro
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HELP! extremely bad MPG w/ supercharger
please post what kind of MPG you get with your supercharger (and what kind of set up u have). also how many miles per tank do u get?
i just had a vortech supercharger installed with a lingenfelter supperram set up (on a 350) and on the first two tanks of gas (since the install) im averaging only 8.5 mpg !!! i get around 100-110 miles per tank...the motor is a 350, rebuilt, new plugs and wires, running mobil 1 synthetic oil...im not even 'heavy footed' this is just basic driving...need help !!!!!! anyone who can lend advice speak up!! ive heard that new motors need break in time and this can cuase bad mpg but 8.5 mpg is rediculous !!! i only run 93 octane too..
i just had a vortech supercharger installed with a lingenfelter supperram set up (on a 350) and on the first two tanks of gas (since the install) im averaging only 8.5 mpg !!! i get around 100-110 miles per tank...the motor is a 350, rebuilt, new plugs and wires, running mobil 1 synthetic oil...im not even 'heavy footed' this is just basic driving...need help !!!!!! anyone who can lend advice speak up!! ive heard that new motors need break in time and this can cuase bad mpg but 8.5 mpg is rediculous !!! i only run 93 octane too..
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Re: HELP! extremely bad MPG w/ supercharger
only roots blowers are supposed to give bad mpg all the time..
btw, i get 8.5 mpg N/A...
btw, i get 8.5 mpg N/A...
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Re: HELP! extremely bad MPG w/ supercharger
I don't know where you heard that....... if you drive a roots with a light foot it will get better gas milage than without !
Last edited by flrtin1; 12-14-2007 at 11:40 PM.
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Re: HELP! extremely bad MPG w/ supercharger
I agree with xpndbl3, if you truely are driving with a light foot ( hard to do with new power ) and getting poor milage I would look at your tune.
Last edited by flrtin1; 12-14-2007 at 11:41 PM.
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Re: HELP! extremely bad MPG w/ supercharger
i get about 5....N/A...cant wait till the blower is on...wohhhooo
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Car: 89 trans am GTA,90 model trans am 350 tuneport,87 firebird
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Re: HELP! extremely bad MPG w/ supercharger
I know what you need to do!!!!!!
Take the SUPERCHARGER OFF GIVE IT TO ME,YEA!!!!!
THAT will make the gas mileage better!!!!!!!
lol
Take the SUPERCHARGER OFF GIVE IT TO ME,YEA!!!!!
THAT will make the gas mileage better!!!!!!!
lol
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Re: HELP! extremely bad MPG w/ supercharger
i know its running rich...as my mechanic told me it is. would leaning it out a bit help? also, can some explain to me exactly what is involved with tuning a supercharged vehicle? what is tested/checked/changed? and how exactly is it done?>...i would like to know as im new to having a supercharged car.
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Re: HELP! extremely bad MPG w/ supercharger
i know its running rich...as my mechanic told me it is. would leaning it out a bit help? also, can some explain to me exactly what is involved with tuning a supercharged vehicle? what is tested/checked/changed? and how exactly is it done?>...i would like to know as im new to having a supercharged car.
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Re: HELP! extremely bad MPG w/ supercharger
I don't know if this will help you but.. It might be in the F.M.U. Thats the fuel managment unit. Got to see if its working right under boost applications. I think your fuel pressure should be around 35-40psi driving around without boost. Under boost it will spike up a little more depending on fuel demand (where dyno tuning comes in.) My car would spike fuel pressure to around 80psi under hard boost (12psi). But still got around 190-200 miles a tank with a 383. Good luck
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Re: HELP! extremely bad MPG w/ supercharger
Back on topic, a good dyno tune is probably just what you need
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Re: HELP! extremely bad MPG w/ supercharger
Actually only the newer Eaton's have the bypass valves. The Wieand's and B&Ms don't bypass them. They supposedly increase MPG because they're more efficient at stuffing air into the engine.
All this talk is making me jealous that my 144 is just supercharging my work bench.
So far with the mods in my sig I'm only able to get 15mpgs, but I didn't build it to baby it.
All this talk is making me jealous that my 144 is just supercharging my work bench.
So far with the mods in my sig I'm only able to get 15mpgs, but I didn't build it to baby it.
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Re: HELP! extremely bad MPG w/ supercharger
Weiand says they use the bypass valve on their blowers, you sure they don't?
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Re: HELP! extremely bad MPG w/ supercharger
100%, took mine apart, but mine's the smaller 142/144 variety, not sure about the big boys, but dunno why those would. They told you that on the phone?
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Re: HELP! extremely bad MPG w/ supercharger
No, it was in their supercharger catalog. The catalog has a good sized section where they go over supercharger details and info. I suppose that doesn't at all make it true, but I didn't think they'd fib on that
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Re: HELP! extremely bad MPG w/ supercharger
You need to put a Wide Band O2 on the car. With out that your driving blind.
Tuning off the narrow band just won't cut it anymore. I use the AEM Widband on my stock ECM Cars.
Tuner pro will be able to edit your factory ECM. If your using a FMU... Ditch it. They are not going to give you the right AFR for all driving that a street car does.
If your not willing to learn how Tuner pro works and alot of stuff about hacking the factory ECM then go Aftermarket. FAST... or DFI. It's much more user friendly.
There's no reason why your getting the MPG you do except for a very Poor Tune.
~Scott.
Tuning off the narrow band just won't cut it anymore. I use the AEM Widband on my stock ECM Cars.
Tuner pro will be able to edit your factory ECM. If your using a FMU... Ditch it. They are not going to give you the right AFR for all driving that a street car does.
If your not willing to learn how Tuner pro works and alot of stuff about hacking the factory ECM then go Aftermarket. FAST... or DFI. It's much more user friendly.
There's no reason why your getting the MPG you do except for a very Poor Tune.
~Scott.
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Re: HELP! extremely bad MPG w/ supercharger
i do have the FMU installed from vortech...(ur50slow) can u expalin why the fmu cant handle the needs of everyday driving? (this is not a strip car but as much of a daily driver as possible...but as powerful it can be as a DD with decent gas milage). i spoke with my engine builder, he told me he did a very basic tune on the car just to help break it in as the engine was rebuilt in addtion to the vortech supercharger and lingenfelter top end. i told him about my terrible gas milage and he said we could address that once its good and broken in (were agreed around march--giving it plenty of break it and daily use over that time period), he did mention getting it on the dyno at that time and doing a proper tune, as of now it hasnt been on the dyno yet.
can ui explain to the difference between 'wide band' and 'narrow band' ? im not familiar with the difference...thanxx
can ui explain to the difference between 'wide band' and 'narrow band' ? im not familiar with the difference...thanxx
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Re: HELP! extremely bad MPG w/ supercharger
The FMU is nothing real fancy.
Your normal Fuel Pressure Regulator increases fuel pressure 1-1 with boost.
So every 1 psi of boost you get 1 more Psi of fuel pressure.
Your FMU however is setup depending on a diaphram inside to double/triple or more your fuel pressure depending on boost. So... Your boost go's up 1 psi and your fuel pressure go's up 2 or 3 or more depending on the disk inside.
Now.. with that being said... your ECM knows nothing of of this FMU. It's got the factory programing inside and it will account for some rich/lean in the Intergrator/BLM's (block learn) numbers but it can only adjust so much.
A FMU will never get you a proper fuel curve pushing extra fuel through stock or bigger injectors with the Barro/humidity/temp changes.
And it's not easy on fuel system parts having so much pressure on them when in boost.
If you decide to edit your ECM and install the proper Fuel Injectors for your HP level you'll end up with a longer living fuel system and a custom program that is able to adjust it's self on a daily basis and it's not going to fail as easily. With a system like Tuner Pro you can adjust your spark curves, fuel curves... Cold running/open loop/Idle ect It's limitless realy. But it's going to take some time to learn it.
Now... A Narrow band O2 reads in Mv. (Millivolts) You can tune with one but it's designed to read 14.7-1 Anything above or below it's not as accurate.
(Also called a one wire O2/ or can have 4 if it's heated)
A Wideband allows you to read actual AFR (Air Fuel Ratio) It's accurate over a wider range of your air/fuel that your car experiences.
It's much easier and more accurate to tune with one once you know what AFR to tune for.
Boosted cars like 11.7-11.3AFR at WOT and you can narrow the AFR's down to 14.7-15.3 (Or leaner) when crusing/light load. That takes more experience with tuning and timing to get right.
Being Pig rich isn't always a good thing either. If it's 6mpg and the afr's are 10's all the time you'll end up with fuel in your oil and it's not going to be a good thing.
A Dyno in my openion is a waste of money and time. Your much better off to tune in "real world" conditions with the wind and actual road load on the car. You could tune WOT on a dyno and get some "Numbers" for you to look at but it's not going to dial your car in for every day driving.
There's so much more to tuning than I can explain in a few paragraphs but this is a basic start behind what it takes to program for daily driving with factory ECM's.
The Wide band go's in a 2 1/16th pod on your pillar. 2 wire hook up. (Positive/neg.) and the other lead go's to the 7wire O2.
Be glad to help anytime,
~Scott
Your normal Fuel Pressure Regulator increases fuel pressure 1-1 with boost.
So every 1 psi of boost you get 1 more Psi of fuel pressure.
Your FMU however is setup depending on a diaphram inside to double/triple or more your fuel pressure depending on boost. So... Your boost go's up 1 psi and your fuel pressure go's up 2 or 3 or more depending on the disk inside.
Now.. with that being said... your ECM knows nothing of of this FMU. It's got the factory programing inside and it will account for some rich/lean in the Intergrator/BLM's (block learn) numbers but it can only adjust so much.
A FMU will never get you a proper fuel curve pushing extra fuel through stock or bigger injectors with the Barro/humidity/temp changes.
And it's not easy on fuel system parts having so much pressure on them when in boost.
If you decide to edit your ECM and install the proper Fuel Injectors for your HP level you'll end up with a longer living fuel system and a custom program that is able to adjust it's self on a daily basis and it's not going to fail as easily. With a system like Tuner Pro you can adjust your spark curves, fuel curves... Cold running/open loop/Idle ect It's limitless realy. But it's going to take some time to learn it.
Now... A Narrow band O2 reads in Mv. (Millivolts) You can tune with one but it's designed to read 14.7-1 Anything above or below it's not as accurate.
(Also called a one wire O2/ or can have 4 if it's heated)
A Wideband allows you to read actual AFR (Air Fuel Ratio) It's accurate over a wider range of your air/fuel that your car experiences.
It's much easier and more accurate to tune with one once you know what AFR to tune for.
Boosted cars like 11.7-11.3AFR at WOT and you can narrow the AFR's down to 14.7-15.3 (Or leaner) when crusing/light load. That takes more experience with tuning and timing to get right.
Being Pig rich isn't always a good thing either. If it's 6mpg and the afr's are 10's all the time you'll end up with fuel in your oil and it's not going to be a good thing.
A Dyno in my openion is a waste of money and time. Your much better off to tune in "real world" conditions with the wind and actual road load on the car. You could tune WOT on a dyno and get some "Numbers" for you to look at but it's not going to dial your car in for every day driving.
There's so much more to tuning than I can explain in a few paragraphs but this is a basic start behind what it takes to program for daily driving with factory ECM's.
The Wide band go's in a 2 1/16th pod on your pillar. 2 wire hook up. (Positive/neg.) and the other lead go's to the 7wire O2.
Be glad to help anytime,
~Scott
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