KA-T getting good mpg's?

[chi0082]

Hi I was wondering what you guys are getting as for mpg's on your turbo'd KA's? Especially those who are upwards of 300+ hp's with good tunes. Are you getting anywhere near 25 mpg's? better/worse?

[Chaluska]

on my old S13, I had a simple T28 setup, pushing about 240whp @ 12psi

if i was heavy on the boost, i would rank in about 19-20 mpg.. if i stayed out of boost, i usually got 27-29mpg (50/50 city fwy)

The tune was enthalpy, with 550cc injectors, Z32 maf, atmospheric SSQV, T28 / ssautochrome manifold, 3" exhaust, everything else was pretty much stock.. No engine work

[DevilMB3017]

In boost and beating the crap of my car for a whole tank of gas nets me about 12-14 MPG approx.

Out of boost on the highway got me about 26 MPG approx.

More info in sig.

[EstoMax]

the best i got was filling up with a warm engine, driving 100 miles on the freeway, and filling up again. I got 31mpg that time. I thought my gas gauge was broken because it did not move at all

usually (on most tanks) i get around 20 mpg, thats with mixed boosting/city/highway driving. If i stay out of boost and drive like a good boy i get 24-25. (basically same as stock)

Marko

[zerepdivad]

IF i stay out of boost i get ok gas mileage, honestly it seems that my gas mileage on my dohc ka-t is better than on my sohc na auto daily driver.....No clue on numbers but it's decent nothing spectacular

[480sx]

Its not hard to get 28 mpgs out of a well running Ka-T, thats about the norm. You can get more on the highway with a SAFC and a leaner AFR.

[neverlift]

IF i stay out of boost i get ok gas mileage, honestly it seems that my gas mileage on my dohc ka-t is better than on my sohc na auto daily driver.....No clue on numbers but it's decent nothing spectacular

but its my friends 5spd n/a truck, he had a half tank and used almost all of it for a 25mile trip.

a decently tuned ka-t should not have a hard time getting good mileage,IF everything is sound, I personally can use way less pedal with a turbo motor...

my buddies sr'd 13 coupe couldnt do the five dollars and slide for an hour thing

[krazydriver]

With my DIY megasquirt tune, i've gotten as high as 31mpg, specifically driving easy on it (shift before 3k, no boost) just because i wanted to see what it can do.

Generally though it's about 23-25mpg

forgot to add, 188k mile KA no rebuild, with a t3/t04 and 7 psi.

[neverlift]

hey how is the d/p treating yah?work ok?

yeah I recently got 33 or so, going off the odo, not trip meter. I could be a mile or so off... a lil boost in the mix not much.

[lrb_2000]

I get around 32-34 on the highway out of boost... In town, I still get around 25-26.. I have a really good tune, I keep my cruising afr's around 16:1..

[spooled240]

commuting on the freeway around 75 mph, I'm getting around 25-27

[sunnys14]

Around town I get 18mpg.

Cruising freeway I get 21mpg.

This is all with me staying out of boost.

[spooled240]

^damn that kinda sucks, are you running really rich?

[shimizu_17]

I prob get like 14 around town and like 18 on highway without going in boost. Way less If I am boosting.

Got a Greddy 20g turbo, JWT ecu, 550cc injector, Z32 maf tune and no correction made on my safc 2 yet.

[spooled240]

I prob get like 14 around town and like 18 on highway without going in boost. Way less If I am boosting.

Got a Greddy 20g turbo, JWT ecu, 550cc injector, Z32 maf tune and no correction made on my safc 2 yet.

i also have a jwt ecu, 555cc injectors and a z32 mafs and I can go 110 miles and use about a quarter tank(4 gallons)

yesterday I was just about empty and I filled up with about 11 gallons and I got a little over 3/4 of a tank, isn't this a 17 gallon tank??

[lrb_2000]

Yeah, but I think like 2 gallons are reserve... I can get my gas gauge to go way below the empty line before i'm actually out of gas.

I'd be pissed if I was getting less than 20mpg... If you're not in boost, nothing should change. If you have at least a safc and wideband, just lean it out. You don't have to run 14.7:1 AFR when you're cruising. You can go way leaner.

[spooled240]

yeah I was trying to calculate the capacity of the actual tank. I figured that i had a tiny bit of gas(needle was a tad over E) and 11 gallons got me over 3/4's of a tank. So let's just say 12 gallons will get you to 3/4's of a tank, that means the actual capacity of our fuel tank from the E to the F is 15 gallons, which goes along your estimation of a 2 gallon reserve

so now I'm wondering how accurate the gas gauge is...should I start estimating my mpg off the 15 gallon capacity? Because the gas gauge doesn't measure all the gas in the tank.

[sunnys14]

^damn that kinda sucks, are you running really rich?

Nope, my afrs are mid 15's cruising, I have no idea why I burn so much gas....?

[DevilMB3017]

Nope, my afrs are mid 15's cruising, I have no idea why I burn so much gas....?

High fuel pressure? Good AFRs can mean you have a strong ignition to match the extra fuel. The more I'm reading about tuning EFI, the more I realizing EGT is incredibly important for reliability and probably would sort out your fuel consumption questions. It gets overlooked by a lot of people new to turbo motors, including myself. I plan on doing an EGT sensor and gauge within the next year or so, as I have a lot of other things to accomplish first.

so now I'm wondering how accurate the gas gauge is...should I start estimating my mpg off the 15 gallon capacity? Because the gas gauge doesn't measure all the gas in the tank.

Using the tanks capacity and the gauge to guess MPGs is not really accurate. The best way to test this, and the only way I do, is fill up your tank with fuel. Now either write down your milage or reset your tripometer. Drive until your gas gauge goes at least half way down, the further you go will not affect MPG but will allow a more accurate reading. Now go fill up your tank again. Divide the distance you went by how much fuel you just took to fill up again.

[spooled240]

Using the tanks capacity and the gauge to guess MPGs is not really accurate. The best way to test this, and the only way I do, is fill up your tank with fuel. Now either write down your milage or reset your tripometer. Drive until your gas gauge goes at least half way down, the further you go will not affect MPG but will allow a more accurate reading. Now go fill up your tank again. Divide the distance you went by how much fuel you just took to fill up again.

Alright I did this: Topped it off, drove exactly 274.7 miles and then I topped it off again putting exactly 9.2 gallons in.

274.7miles/9.2gallons=about 30 mpg??!!

this was mostly hwy driving but there was definitely a good portion of city driving with some boost here and there. 85% of the time I drive like a granny.

I didn't know I was getting that much, but no complaints here

[DevilMB3017]

Yeah, that's WAY more accurate to get your milage. Do you have different rear-end gearing or tire sizes then stock though? You kind of have to take that into account...At most it's +/- 10%. You're most likely getting 27 MPG, but still!

What diff are you running? What size tires? I'll see if I can figure it out for you.

[spooled240]

nah everything is stock spec basically. I'm running the stock gear ratio 4.08:1 and 16" z32 wheels on a 245/45 tire. Height wise, they are about identical to my stock 15" steelies with the 195/60's. The second time I filled up it clicked at around 8.9 gallons but I put in the extra amount to round to the dollar, so it took about 9 gallons even. The first time I put in like an extra 70 cents.