So I got my VIII tuned to 18 PSI running @220 on mustang dyno. Walboro fuel pump, AMS turboback high flow cat, ARC induction box. I used to get around 240 miles per tank running 94 full stock. I took out the exhaust because it was too loud and got a ticket for it. Now I run the same tune still, but getting 160 miles per tank which is crap. I used to get 200 when still had turboback on . What should I do to get better mileage without spending too much cash?

I'm thinking of getting a tune for my stock exhaust. I dont have my old fuel pump anymore so would it make a difference? Thanks.

 

could be a few different things read this thread
https://www.evolutionm.net/forums/ev...gas-wth-4.html

 

my car had the same problem. intake and exhaust with fuel pump i was getting 160. now with 1200cc and a double pumper im getting almost exactly the same. strange. your tune could be very rich.

 

lol find a stock f pump and install it if u don't care about turning up ur boost for now. Ask ur tuner to take a look at ur fuel map and re flash it. Like already stated above, maybe ur running a lil rich. Is ur MAF clean?

 

I had a bad Oxygen sensor that caused horrible MPG

 

Thought the walboro fuel pump was neccesary for every Evo 8, so I didn't keep the stock fuel pump. my Air fuel is running a tad more rich according to my evo. Im just worried it has to do with anything pricey. I'll be taking my car to the tuner next week and see what happens then.

 

Sounds like a tuning issue, hope nothing big is wrong!