i just recently started using idemitsu rotary premix on my stock 90 N/A. I still have my omp but i decided to run premix just to make sure my motor has that little extra protection from a potential omp failure. i mix it with 1/2 ounce per gallon as the back of the premix bottle and how mazdatrix suggest on their website. my question is should my fuel economy go down when i run premix? i was thinking that with the extra lubrication and better sealing that my engine would be a little more effiecent or at least the same effiecency as what it was before i started premixing? is this a wrong assumption?

 

stays the same

 

For sheezy. hehe. yea mines the same...same being its still shitty. lol

 

oh ok, thanks. yea i need to increase my fuel economy...14 miles per gallon is killing me

 

The pre mix shouldn't have anything to do with you MPG. I guess it really shouldn't matter though, we don't buy these cars for fuel economy.

 

It will hurt your miles per dollar though, since now you're dumping in several ounces of expensive oil per fill, whatever that brand costs.

 

14mpg i hope you have a turbo (my n/a gets around 20-22mpg)

 

What is your secret?

I'm pretty sure my n/a is getting around 15-16mpg.

 

I think economy depends on the motor or something...my old stockish TII got 24 mpg highway. My heavily modified TII I have now gets 15 mph highway

 

turbo II gets aprox 19

 

no it's an NA, it definitely needs a tune up and a fuel tune, i just need to get more money first

 

motor stock (85k org miles), fresh tune up/fluids/ a few mods (exhaust/intake) and i dont really drive over 65mph (speed limit on our freeways here are 55 )

a new stock fc got 24mpg on the highway new i drive pretty mild with it most of the time.

if your getting 15 on the freeway you need to slow down or fix your 7.

 

yea i'm planning on changing the spark plugs. I've read somewhere that might help. I've only had the car for a couple of months and the old owner wasn't realy a car guy so all he ever did was change the oil. If the spark plugs don't help i think i'm going to change the O2 sensor because i know that's never been changed. Anyother ideas that could help other than those two? (by the way it's an S5 NA with 78K original miles)

 

You'll have to wire brush your spark plugs every month or so from gunky build up. Other than that you don't notice any changes.

 

I have never checked just city or just highway mileage. My weekly driving consists of about 1/3 highway and 2/3 city miles and my 91 N/A Vert automatic gets 17.5mpg and I don't baby it much, hell gotta floor it and wind it out to get the fat pig movin' !

I imagine if I took a long highway trip and kept speed at limit, It might get around 21-22mpg.

 

I'm getting 17/25 with the omp disabled in mine.

 

well mine gets 0 mpg.. then again half the engine is laying on the garage floor right now.

 

uhh my n/a gets 9-12mpg =\ FTL .. don't carb your 2nd gen! LOL

 

MY TII gets about 20mpg with the OMP and premix....bad plugs and wires will kill any cars mpg. do a COMPLETE tune up and you should get about 4mpg more

 

or learn to tune.