The Puget Sound Mini Club had a dyno day this Saturday and I had a chance to have my 2004 MCS MC40 on the dyno for the first time. A great opportunity to see what the mods have yielded so far.

Here's my configuration:

- 2004 MCS
- 15% Alta V2 pulley (stock belt)
- Alta V2 CAI
- everything else is stock

I was pretty satisfied with the results. When looking at the HP and torque curve, there's a decent dip around 4,000RPM in the blue line. This also resulted in a dip in HP. The blue line represents the first run. The red and green line are run 2 and 3. So, I'm wondering what have caused the torque/hp dip in the first run.

Could it be the SC belt? I'm wondering if it started to slip as it got warmer?

Any of the pros here have any input?

Thanks!

 

Nice to see un-biased Dyno figures. These look really good. There is no indication of belt slipping. All three of your runs are close. Nice job !

 

I'd swap your belt. I got a fair amount of slippage with the stock belt with my 15% pully. Otherwise looks good your car is right up there with a decently strong lightly modded mcs. With a tune you'd easily be up in 190-200 with gobs more tq.

 

so what do you mean by "unbiased"?

 

thanks for posting that pretty set of runs

what does the butt dyno say about the car? feels good?

this level of tune seems to generally shift the flywheel numbers to the wheels - meaning a 15-17% boost at the wheels. basically the mods negate all driveline losses compared to a stock cooper s.

for me 170 at the wheels feels a heck of a lot better than 170 at the crank!



and by the way, the dealer installed works kit i've dyno'd pulled 160 for torque and 165 for hp at peak (i know, compare dyno results at your own risk) so i reckon you have a lot of bang for your buck right there!

 

So what makes all the others biased Nitro .

Longboard

 

Your boss already brought this up ... lol

 

thanks for the bump Mozzarella

 

Car feels good and I'm happy about the results. Every once in a while I feel like around 5,000RPM that there's a little 'torque hole'. So, I've been wondering if it might be the belt slipping at hard acceleration. When I saw the first dyno run (the blue curve) and the dip at 4,000RPM, I was thinking my suspicion about the belt might be correct.

I was all geared up for Jan's tune here in Seattle in June, but I will be out of the country . So, will have to wait until next time and in the meantime try a shorter belt.

Overall, it was interesting to have 13 MINIs on the dyno this weekend and see the differences in year and mods. More performance mods didn't neccessarily translate into more hp/torque. On of the strongest was a 2005 MCS with 15% pulley and everything else stock.

 

Mozzarella!! Good to see your back. Why the name change?

Longboard

 

That would be mine.

 

Wow, if we really did work for Jan that'd be a cool situation. Never showing up to work, not getting paid anything. Paying for all the parts he sells, you know, like most employees do.

 

Yes sir, that would be yours

Looking forward to seeing your numbers after the tune!

 

RedRocketWA's Dyno pull represents with the most basic of proven performance parts an individual without a tune/Flash or tuners support (unbiased) in getting a HP/TQ output. Now if someone like yourself does a Tune for him the results will be better to understand to some that have similar mods that have not gone to the expense of a before and after Dyno pull. Therefore the results after such a Tune say by you in this example could not be considered biased.

 

So ... I got the "participant" ribbon at this event. Alta everything from front to back, but had the worst numbers of anybody (see chart below).

The part that had everyone puzzled was the A/F ratio, which was off the charts bad, and explains why I get 18 mpg. I've scheduled a Friday night in June with Jan. But I went to the dealer today to ask "WTF?" first. If it's mechanical, then Jan's work will be a waste of time. Scoop is scheduled for a once-over next Monday at the dealer to see what may be the matter.

Since I know very little about what I'm dealing with, can I ask if anybody else has heard of similar horror stories?

 

mine put down 204whp with no tune and just cai and 15% pulley.

 

I've seen air fuels like that on cars with stock tunes before. It's no biggy. You'll make more power leaning that out a bit with a tune.

Most of that fuel is going in on the mid range, which means you'll be low on the torque side. Peak AF's are right where they should be.

For what it's worth, your poor fuel economy is likely not too much to do with AF's. You're not going to see a 5-6 MPG jump by leaning that out 1-2 air fuels.

 

Thanks, Nick. That puts my mind at rest. Now I'm definitely looking forward to the June tune!