Mike521

I saw a lot of discussions where people said they got better mileage with a CAI / tune but never noticed anyone posting solid numbers. I decided to do my own test which I finished a couple weeks ago. This is strictly focused on mileage and is mainly for those interested in getting the CAI for mileage reasons. I ignore the added fun factors.

Here's what I did:
-- all driving was done around town (sorry but I didn't have any road trips planned)
-- that means to and from work, the store, etc. cruising speeds of 40 - 50ish
-- I shifted at the manual's recommended shift points and never opened it up
-- JLT 2 intake w/xcal 3 from bamachips (87 performance and 93 performance tunes were used)
[ul][*]2 tanks @ 87 octane with no CAI / tune[*]2 tanks @ 87 octane with CAI / performance tune[*]2 tanks @ 93 with CAI / performance tune
[/ul]Here are the numbers:
[ul][*]87 with nothing - 507.1 miles driven, 27.997 gallons burned = 18.112 mpg[*]87 + CAI / tune - 553.8 miles driven, 28.744 gallons burned = 19.266 mpg[*]93 + CAI / tune - 550.2 miles driven, 27.479 gallons burned = 20.022 mpg[/ul]clearly the 87 + CAI / tune was better than 87 with nothing, so the next question was, did the added mileage of the 93 tune make up for the added cost. The answer is no, here are the numbers for the first tank of gas. I'm sure the result will be the same for the other 5 tanks:
[ul][*]the cost of 87 octane at that time was $3.419. Therefore my cost per mile for this tank (87 with no tune) was 0.1958 cents per mile.[*]Taking the averages of both the 87 + CAI / tune tanks, and assuming I burned the same amount of gallons, I would have driven 269.443 miles, a difference of +25.243 miles. The cost per mile would have been 0.1774 cents per mile[*]Taking the averages of both the 93 + CAI / tune tanks, and assuming I burned the same amount of gallons, and the cost of 93 octane at the time ($3.799), I would have driven 280.0155 miles, a difference of +35.815 miles. The cost per mile would have been 0.1877 cents per mile.[/ul]I can do the math on the next 5 tanks, but I started for tank 2 and the differences in costs per mile were almost exactly the same, so I probably won't bother.

So the conclusions are:
-- 87 with CAI / tune is better than 87 with nothing
-- 87 with CAI / tune is the most cost efficient combination
-- 93 with CAI / tune is the most fuel efficient combination

So there it is. Now the summer is here so I'm switching to 93 / torque, forgetting about mileage and having some fun. But for anyone who cares, at least there's some real numbers. One day if I ever do a long road trip I'll do the exact same thing but with highway miles instead.

speedstang06

good to know, thanks!

paulsoo217

interesting. So CAI + Tune does improve mileage. What if there's CAI but no tune? And what kinda tune is that?

Mike521

anytime speedstang

paul, I'm not sure about the CAI / no tune, my CAI requires a tune (or at least it claims it does and I'm not gonna argue lol)

my tunes were from bamachips, same guy I got the intake from. he has descriptions on his site about performance vs torque, I got the impression torque would be less fuel efficient and that it was more about making the car pull harder in the lower RPMs so I left that outta the test (and I was sick to death of driving so damn slow)

MustangFan45

Awesome! Now I know. I would like to see gas milage changes with a Whipple and exhaust system

Orion_240

of course, with the CAI and tuner (cost?), how long will it take for the slightly better mileage the pay off? And with higher octane gas it never will, right?
I'm too tired to do the math myself...

Nuke

Payoff???? The payoff is the performance gain. Once again, we spend near $30K on a performance car and some of us quible about payoff for saving 1-2 MPG. Give me a break...

Mike521, GREAT JOB and thanks for the detailed info. Although I keep detailed fuel mileage records, I've never taken the time to perform detailed testing like you have. It confirms what I suspected from all the forum members input on this topic. There is a minor increase but you won't save enough to recoupe the $600 for the CAI & tune, but who really cares? It's great to know that we're not LOSING anything (except a few pennies perhaps) while gaining performance.

Kara

Very awesome. Thanks for this info. It just justified me getting a 93C/A andtune

Mike521

anytime guys, I'm glad everyone finds it interesting

Orion, the only way for it to justify the cost of the CAI / tune would be to run 87 for however long it takes, I didn't do the math on that either but I'm sure it'll take a few years. But it looks like the fact is, eventually, you will get your money back

I think everyone will be most happy to see that running 93 isn't as expensive as it feels like when we pay, the reality is we only spend a few bucks extra per tank, and the fun factor makes up for that easily. (and we can say we're doing our part for the environment by making our cars as fuel efficient as possible)

tn_gt

great research, thanx a lot...one thing i had a question about was how come the premium fuel was nearly $.30 higher than regular? i understand it could have gone up with the difference in time, but shouldnt you calculate what the price would have been at the time you filled up with the regular? thats like saying if you filled up with premium and it just happened to be the same price as reg when you did that test, then premium would have prevailed big time...maybe i read that wrong in your test but im open for critizism lol...but great post