Author Topic: mpg for gti 8v?  (Read 2998 times)

Offline Bigdunc

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mpg for gti 8v?
« on: 12 October 2010, 19:44 »
hi guys just wondering what the adverage mpg the 1.8 8v gti should do, i recently had myne cammed and now its only reading about 23mpg im guessing this is low and how would i go about changing the mixture to make mpg go up?

Thanks

Offline Ben Lessani

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Re: mpg for gti 8v?
« Reply #1 on: 12 October 2010, 21:08 »
Search, been covered 1.8 billion million trillion zillion gazillion times

Offline Haribo!

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Re: mpg for gti 8v?
« Reply #2 on: 12 October 2010, 22:36 »
Mines pretty standard and averages 32.7 but on a long trip can average around 40

Offline Bigdunc

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Re: mpg for gti 8v?
« Reply #3 on: 13 October 2010, 09:46 »
I need myne adjusted then. I know I got a high lift cam but shouldn't be that bad lol, do I turn clockwise to improve mpg or anti?

Offline rob.043

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Re: mpg for gti 8v?
« Reply #4 on: 13 October 2010, 10:00 »
Dont mess with mixture screws to adjust MPG!  The idle and co adjustment is there to ensure the mix is correct for emmissions and efficient combustion, it will probably need reset fot your new cam tho. Have a look at the guide in the maintinance section and follow that (if its digi). Once its set correctly see if consumption improves.

I have a digi 8v with a 260 degree duration cam (so a mild upgrade) and still get around 37mpg to a tank, when its getting driven hard for a bit, or over 40 on a longer cruise. Dont just go with what the on board computer says, do a check with a calculator when you fill up at the petrol station to see if its accurate.

Offline Bigdunc

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Re: mpg for gti 8v?
« Reply #5 on: 13 October 2010, 17:31 »
is this thread basicly what to do? even though i have the high lift cam?
http://www.golfgtiforum.co.uk/index.php?topic=33253.0

Im going back this sat morning to get it looked at and set up mixture using the co meter, im guessing if im only getting about 20mpg then poss the cam isnt timed correctly?

the car seams to run fine i cant see a prob with the general running just the fuel consumption

Offline JimR

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Re: mpg for gti 8v?
« Reply #6 on: 13 October 2010, 19:04 »
Do you guys believe your readouts? Mine recently said 34mpg over a £50 fill up, realistically though:-

£50/£1.15 (per litre) =43.5 litres

43.5 litres = 9.56 gallon

250 miles to tank

250 miles/9.56 gallons = 26mpg

Painful
Mk2 GTi.

Offline rob.043

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Re: mpg for gti 8v?
« Reply #7 on: 13 October 2010, 19:23 »
Quote
is this thread basicly what to do? even though i have the high lift cam?
http://www.golfgtiforum.co.uk/index.php?topic=33253.0/




Thats the one, follow that to tune your digi properly. If you follow it and replace the blue temperature sender, get a genuine one from volkswagen, as the aftermarket ones have been commonly known to be poor, and not work as well. But you can try it with your existing one first. I think you should set the timing to the standard setting, dont advance it from the standard setting for your cam, as the ecu will do this (i think).

As my car has a cone filter, my readout is low, like 20's, when im getting 350 miles or more to a tank. Another reason im looking for a standard air box, so the vac lines are hooked up as VW intended...
« Last Edit: 13 October 2010, 19:25 by rob.043 »

Offline Rodriguez

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Re: mpg for gti 8v?
« Reply #8 on: 13 October 2010, 19:53 »
From personal calculations and reading other threads, I'd guess that the MFA is about 20% too optomistic. I can get mine running at a indicated 50 mpg!!!!


Normally works out at 38-39 over a tank....





Cheap motoring :nerd:

Offline Bigdunc

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Re: mpg for gti 8v?
« Reply #9 on: 13 October 2010, 22:21 »
my readout was about 27-32mpg befor my cam was installed so im wanting it back to about that setting, i know the setting atm is not correct as i can smell the petrol from the exhaust smells like my old driver when the carb was running wrong. booked in for sat to get the co meter on and get the cam set correct to the manafacture settings though might try getting it close to the standard settings.

I also have a cone filter would it help to change back to the standard airbox and just put in a K&N?