Greetings members,

I wanted to compare the difference, between Turbo and S/C. My interest is only highway MPG. on the stock Z the MPG is around 23 or so. I know with Turbos under vacuum, we are actually itemizing the air which makes it burn better.

I got 33MPG going 65MPH, and 28.8MPG going 73MPH

 

Once you put test pipes in and especially when you have a longer O2 bung to fool your computer, your dash MPG meter is no longer accurate. The only true way is to divide your mileage by gallons used. I get 28 highway and 16 driving it around and boosting. Oh and a stock Z gets better then 23 mpg on the highway.

 

If you change your rim and tire size your comp is going to be off.I only get 20 highway and 12 to 15 in town.

 

I averaged 33mpg on my cross country trip with an average speed of 80. That was with stock cats before I switched to TPs

 

as soon as you change injctors and play with fuel pressure that computer is useless

 

I know my MPg went up now that I have a turbo ... before it was like 19 and now is 24MPG

 

even if I get some type of OBD II reader would be off as well?

 

Approx. 19 in city traffic; 27 at the freeway.
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'O4 Touring Coupe: FLAWLESS AT!!!, 13k!!!, $2O,5OO!!! NO feathering!!!!!!!!!!!

 

Damn, so does mpg actually increase with F/I? I always figured the opposite.

I'm around 20-21 mpg stock with avg around 35mph... but I only drive a couple miles to and from work, no highway. So crappy mileage + little driving = rare pump stops.

Sorry, back on topic.

 

I'm seeing 15mpg around town, and 20-22mpg on the highway. When I was stock I was seeing 18-22mpg in the city, and 28-30 highway.

 

with the S/C is more straine on the engine, giving you less mpg???

 

Vortech 3.12 pulley, 18-19 mpg city.

Oh yeah, that computer is useless when you change the injectors, mine says I'm getting 40 mpg city.

 

i assume it would be less... hmm... very interesting

 

for sc mpg will be less than stock due to constant parasitic losses.

for turbo in boost, mpg will drop based on the amount of time spent in boost and the boost level. With a turbo, you can stay in vacuum and not utilize any more fuel than stock. If your tuner spends enough time, they can lean out AFRs under vacuum to provide significant economy at the expense of a slightly rougher driving experience.

 

^^^^ X10000. running a lean AFR under part throttle/vacuum is spectacular for gas mileage.

 

is it unsafe to run lean in those applications?

My best was 54 mpg on my computer....no where close of course...but i saw it! As i drove home I thought...this sucker is going to pay for itself!



....nope.

Last fill i was around 18 mpg total...need to do a highway test

 

~ 20 mpg highway cruising with HKS 1000cc

Haltech is reading about 14.2-14.5 at cruising speeds so where the hell is all my gas going?

 

what speed were you going? could certainly be running leaner, stoich at least.

 

about 10-14 avg when playing and about 18 avg when not

 

+1 only way to do it is count the miles and the gallons after that