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Customization
04-18-2012, 09:02 AM
Hello. I currently have 1995 yukon 350 i have a a full exhaust and what apears and aftermarket y pipe and a slightly modified air intake i have a mix of city and highway driving. It appears to be 120 litre tank and 5 litres in the filler tube i currently get 450 km on the first 3 quarters
279 miles ish and in wondering if an adjustable fuel pressure regulater to maintain better injector spray widths. For better fuel mileage. And help would be greatly appreciated, also im thinking of getting a tbi spacer

Doober
04-18-2012, 09:15 AM
So from the sounds of it you're around 10-12mpg? I would make sure everything else is in good shape first... plugs, wires, cap/rotor, timing is correct (or a couple degrees advanced), fuel filter, correct pressure, etc. If you increase pressure you'll likely just increase fuel consumption.

Customization
04-18-2012, 10:52 AM
Where r the fuel filters located

Doober
04-18-2012, 12:01 PM
They're on the driver side frame rail in the door area. It will look like this:
http://contentinfo.autozone.com/znetcs/product-info/en/US/frc/G3727/image/4/

Customization
04-18-2012, 12:14 PM
Ok seem easy enoiugh so screw this one off and screw the new one on and its finished. For the pressure regulate all I would have to do is take the tbi system off and take the old set screw off and add a longer one with a guage

1988 GMC 355
04-18-2012, 12:30 PM
You need to change the filter first and you need to rent a fuel pressure tester kit to see where it is at now.

Doober
04-18-2012, 01:44 PM
The pressure tester/adapter is about $40 from Autozone iirc, I left the adapter in place on mine. A TBI spacer will also likely help with mpg as well.

Customization
04-18-2012, 09:58 PM
thanks guys alot stock pressure should be what 14 psi? with the exhaust and cat delete. and a free-er flowing intake

oops and also could i make a tbi spacer?
and the fuel pressure guage can it be left in ?

Customization
04-19-2012, 07:25 PM
ok so idid some testing lately on the first quarter which take for every to drain i recieved 200km so 125miles so how big is the last quarter anyways. what r u getting for that section... and will the ultimate tbi mods help this and what should the pressure be set at