ok, so for a long time I thought I was gonna go with JCW, for warranty but also resale value, and - an important point for me - because the JCW kits was described as delivering an actual 10% improvement in gas mileage when driven conservatively (= non-spiritedly).

Now, I am leaning more towards aftermarket mods instead of JCW:
I am already at 21,000 miles in 7 months, my warranty will be up sooner than I thought. I am worried about continued maintenance and repair costs after the warranty expires. I do not think that aftermarket mods will reduce the reliability of the car, and therefore I can use the difference in money to safe for future repairs. Plus, my car already has quite a few issues that need to be sorted out, and I just cannot justify loading another 6+k $$ into a car that is not fully sorted out (steering column clacking, throwout bearing - both being looked into at present, AC howl and engine vibrations, also under investigation, just to name a few). Maybe I can put the savings asidfe for all those future windshields
In addition I may be going for rims and non-RF tires first.

So, my question to those who have aftermarket mods similar to JCW kit
(pulley, exhaust, ECU, intake, I figure this is what I would get and is comparable to JCW in performance):

what is your gas mileage like with the mods and 'conservative' driving, compared to the unmodified car? I'm not talking about spirited driving, but mellow city and highway driving, and preferably actual calculated numbers and not the OBC values which are typically overoptimistic.

TIA!
Markus

 

Dove car to Lime Rock this past weekend and got an average of 30.6 mpg at speeds of 80 to 90 on NYS Thruway. Almost the same as my 2002 S without the JCW kit. Sorry haven't kept track of around town. My foot is always hard on the pedal.

 

So far in my 2003 MCS bought Feb 03
With Madness intake only: 28 mpg in mixed driving, 34 mpg on highway at 60mpg
With Madness intake, 61mm throttlebody and quicksilver exhaust: 26 to 27 in mixed driving, 30 on highway up to 70 mph
No Pulley or Ecu yet. Always use 91 octane gas. No cruise control.
My guess is that the aftermarket upgrades and JCW kit produce about the same changes in miles per gallon.
It's hard to hold back and drive conservatively.
My worse gas mileage was 21 mpg with a day on the track. Not bad. I once got 24 mpg with very heavy city traffic

 

>>So far in my 2003 MCS bought Feb 03
>>With Madness intake only: 28 mpg in mixed driving, 34 mpg on highway at 60mpg
>>With Madness intake, 61mm throttlebody and quicksilver exhaust: 26 to 27 in mixed driving, 30 on highway up to 70 mph
>>No Pulley or Ecu yet. Always use 91 octane gas. No cruise control.
>>My guess is that the aftermarket upgrades and JCW kit produce about the same changes in miles per gallon.
>>It's hard to hold back and drive conservatively.
>>My worse gas mileage was 21 mpg with a day on the track. Not bad. I once got 24 mpg with very heavy city traffic

Aloha minihune,
thanks for posting your info!
How did you ever get 21 mpg on a track day?

M.

 

Plus, my car already has quite a few issues that need to be sorted out, and I just cannot justify loading another 6+k $$ into a car that is not fully sorted out (steering column clacking, throwout bearing - both being looked into at present, AC howl and engine vibrations, also under investigation, just to name a few).


Hey I have steering wheel cracking that's slowly getting worse. I have an appointment in 10 days...

Stock S I averaged 22-24mpg overall (mostly city). Now with Madness intake and Helix P&D pulley, while driving faster and pushing the MINI harder, I average 25-26mpg. Same mostly city driving. The intake helped a little bit. But the pulley, even with the harder driving, increased gas mileage.

I usually get gas a bit after I hit 1/4 tank left. I used to get gas at 210-230 mile range. Now I usually go 240-255 miles and once I almost made it 300!

Hey better mileage is great and all...but not even a little of the reason I got the pulley!

 

no mods here
21 city 25 hwy consistently. Is my foot that heavy?

 

I haven't really noticed any change in mileage after mods. Driving style has stayed the same (I get a little "spirited" now and then when all alone on lonely twisties, but mostly sane driving), and mods were all done about the same time. Magnaflow exhaust, bmp intake, Alta 15% pulley, Powerchips ECU remapping.

 

What explains the apparently better mileage with the pulley? Your stuffing more air in, so isn't more gas being stuffed in as well? INteresting ...

 

My theory is, the increased torque causes the driver to downshift less often.

 

>>My theory is, the increased torque causes the driver to downshift less often.

Aha, that makes sense.

 

I must say, however, I noticed a very noticeable :smile: decrease om gas mileage when I added the UUC exhaust. i attribute this to the extreme free-flowing nature of the exhaust - I'm burbling like crazy in 1st through 3rd gear when lifting off the throttle. Lots of gas burning in the pipes on the way out! It's a beautiful sound though and well worth the extra gas!

 

With my intake, 19% pulley, and Borla Race Exhaust, I average about 26 miles per gallon with my MCS and that's driving it hard and redlining the shifts. I can get about 33 or so on the highway.

RaceCarDriver