I recently had a M7 CAI, Ultrik cam and a 15% pulley installed on my '05 MCS. In addition to being a bit quicker, I seem to be experiencing an INCREASE in fuel efficiency. According to my computer, the stretch of road that I used to average ~31 mpg is now getting ~ 34 (cruise on at 70mph)..I confirmed my findings twice. I understand that those computers may not be accurate, but they should be at least consistent, right?

Mind you, I am not complaining , but I as puzzled as the White House over Scotty's book.......

 

Sounds possible. You've removed some airflow restrictions (engine works less to pump in air), you've slightly increased low rpm boost (same effect), and it's also possible your engine may be running a bit leaner than before (due to the cam/valve overlap and so on). If your engine was running slightly richer than optimal before (not surprising with boosted factory motors), you're now closer to optimal, which means engine efficiency is up.

Congrats!

Do make sure you're tuned well though, you don't want to run too lean.

 

This is NOT uncommon. With the right air flow mods (as you have done) as well as s reduction in use of the go pedal, you can in MANY cases make significant gains in MPG.

I think the MINI is an excellent platform in the days of $5 a gallon gas.

On my R56's with our mods I have consistently gone from 32-34 mpg free way to 36-38! More power, less fuel consumption and a TON of grins as a result. What more could someone want?

Thanks for the post.

 

i would calculate on fill ups just to double check, but yes that is possible. i had a sentra ser that did the same avereaged 23mpg added basic bolt ons and went up to 27mpg.

my conclusion on the reasoning, is the added airflow. this will yes add hp but during cruising speeds this also alows air to move easier through the engine makeing it not run as hard and more efficiently

right, wrong or indifferent this is what i came to

 

thats really funny though as i was typing you guys posted haha i was going to be the second post

 

Could be different fuel. Oxygenated vs non-oxy, or some other variation in fuel quality.

 

Could be that you lost weight so that you could fit into a speedo over the summer?
Less weight = better mpg

 

I'm going to go with this theory

 

After Dan at GrassRoots Garage added a M7 CAI and 15% Craven Speed pulley, my mileage has improved about 2 mpg's overall. Calculated the old fashioned way (no computer) using several tankfuls.

 

^ after Dan did my one-ball mod, my mileage went down about 2 mpgs . . . probably 'cause I end up reving the engine 1k-2k rpm higher to enjoy the exhaust note

 

Your upgrades might make your MINI more efficient so that you can get better mpg if you drive sanely.

But being more fun to drive means being on the throttle a bit more or longer and that will hurt mpg.

Check the overall mpg manually using how many gallons used and miles driven not with the trip computer which usually over estimates/calculates mpg.

 

After my Borla was installed, that complimented with my DDM seemed to add a few MPG according to the onboard. Went from about 27 to just over 30.

 

A ton of people think that manufacturers have completely optimized their engines and calibrations. They haven't. They get enough MPG to reach the spec. They get enough combustion to meet their emissions targets. They get enough HP/Torque to meet their performance specs, then they may tweak it a bit more if they've got time (yeah right...).

Fact is, they are building cars for mass production, because the average guy doesn't need a K&N low restriction intake, a high flow exhaust, or any number of other mods.

The stuff we do to mod a car is above and beyond what the company wanted or needed to meet production requirements. Some people are willing to sacrifice some emissions controls to increase horsepower (this is not intended as flame bait, treehuggers!), some are willing to sacrifice longevity to get more performance. The manufacturer has a whole set of other requirements that you may not share.

So yes, some mods will increase MPG and performance due to better optimization. Some will increase it at the expense of other factors. It'd be interesting to know how much the drivetrain system can be optimized post-production without emissions or longevity loss, but the cars are likely too new to make that determination yet.

 

I understand those trip computers aren't accurate, but it's the same method used to calculate before the mods. BTW, Dan @ Grassroots did my mods, too. Sounds like a few of us are experiencing a pleasant surprise from his touch.....

 

my gas mileage sucks by the way, i avereage 23 driving like a nut and 23.7 driving conservignly, but since im not worried about .7 mpg i drive like a nut vroooom vroom

 

After adding an intake and free flowing exhaust, I haven't seen any increase in mileage. If anything, a slight decrease. Most of my driving is on the highway and I get around 35mpg indicated (~32 calculated). I seem to remember that after adding the intake, my vacuum while cruising the highway went down by an inch or two of Hg. I'll be adding a pulley to the mix soon so I'll keep an eye on what that does.