I would like to increase the power of my 08 MCS but i don't want to sacrifice fuel economy. It would be great if i can get a list of MODs with its performance gain and MPG gain or lose.

I am especially interested in turbo discharge pipe, Jan's ecu tune, jwc tuning kit. Any mods there that increase performance without sacrificing fuel economy?

 

I have Alta CAI, Alta catback (connected with the stock DP with a custom 3" pipe) and I have seen my 75mph cruise speed go from 34/35mpg to 39/40mpg on my daily commute. I can stomp it and feel a nice increase of power over stock but I cannot tell you for certain the performance increase numbers.

 

anyone with DOS intake ? what's your performace gain and MPG gain or lost?

 

Pre-Mods:
164 whp (based on Jan's experiences with that particular dynapack below)
32mpg, hwy

Mods:
Alta CAI, catback, intercooler, and cold-side turbo intake
VIP hotside muffler delete

Post-Mods:
176 whp (dynapack)
34 mpg hwy

RMW Tune:
202 whp (dynapack)
36 mpg hwy


All told, fuel economy is much more influenced by driving styles. My lead foot seldom allows me to reach peak fuel economy.

 

wow, RMW tune give you extra 26 whp with 2 MGP more. Anyone else with similar result?

OPC you went from
164 whp with 32 mpg to
202 whp with 36 mpg. That's amazing how you get that much more power with better fuel economy.

 

At highway cruise and city driving, we found that the A/F's are very similar to stock & no drop in MPG with the DoS CAI .

Like OPC mentioned, that really big question to ask yourself is: After you've modded your car, whether it's with our parts or anybody else's, will you be able to still drive conservatively and keep my MPG's high even though it's more fun to put your foot in it and feel the fury of those mods?

 

I put on a RR catted downpipe and haven't really noticed any difference in MPG, i also put on blizzaks, so i blame those for some of 1 or 2 mpg loss on some highway trips

 

You don't. You get one or the other. That peak HP was at 5083rpm. You cannot rev the engine that high and still expect good fuel economy. I normally shift at 3500-4000RPM.

Edit: I should also mention that fuel ecomomy being so sensitive to driving style really makes it tough for us regular folks to get a consistent reading. For all I know I've mellowed in my driving style allowing for the better economy. Was it the newly cleaned air filter? More consistent tire pressure? You get the idea....

 

of course i know you can't get good fuel economy with constanly shifting at high RPM. It's just nice to have all that power increase available when you needed it, and get better fuel economy then stock MSC when you're taking it easy

I am thinking of buying

Intercooler
DOS intake
Boost tube (hotside)
Jan's tune
i like to feel the increase in power but at the same time don't want to sacrifice too much fuel economy. With all these mods, will my MPG stay the same, giving that i drive the same is i am now, and get that extra kick when i gun it ? Currently i am getting 32 MPG with mix city and highway.

 

Right now:
Alta CAI
Alta hot, cold, and intake tube
Helix FMIC
JCW exhaust

If I could keep my foot out of it I can get 35mpg or better. But alas I can not and I get around 28 to 32mpg.

 

Go with Helix or Forge.
Good choice.

From who?

Jan is the Man!

You know, I think one of the reasons the tune doesn't hurt the fuel economy is because it helps smooth out the throttle response. My MINI used to hesitate a lot at street lights on take-off. There was this lurch involved that forced me to giving it more gas and feather the clutch more than I would have liked. Almost like jackrabbit-starts. The mods helped a little, the tune got rid of it entirely.

 

If your interested in Jan's tune, it would be well advised to go ahead and sign up for the flash tool. It enables you to flash the ecu back from tuned to stock at any given moment. Theres a massive group buy going on right now for it. Look it up dude. You may just save a hundred bucks.

 

My car picked up 4+ mpg when I flashed it. I spent a considerable amount of time in the flash tuning for fuel economy. I expect the next LONG high way trip to be over 40mpg.