To find out just how much power Project Evo, our Long-Term 2008 Evo GSR, currently generates, we went to someone who knows these cars.
Road Race Engineering has been working on Evos since before they were sold in the USA. And they've been building, racing, tuning, modifying and repairing 4G63s since 1994. You could say they know a thing or two hundred about how to make Mitsubishis go fast.
In Road Race Engineering's huge 6,000 square foot facility in Santa Fe Springs, CA, they got to work. Project Evo's wheels came off and the four Dynapack hub dynos were carefully bolted on.
Then we fired the engine, warmed it up to operating temperature by "driving" at light load and did a few pulls.
Now, before we go any further, it's important to remember that not all dynos are created equal. Comparing results from different dynos is a fruitless and deceptive exercise. Even if you test the same car on two different dynos on the same day, the results can be all over the map.
In fact, we've already done that exercise with a GT-R--remember this test?
Since you just clicked that link and re-read the test, you know only to compare results from Road Race Engineering's Dynapack dyno to other runs made on that dyno. A dyno is a tuning tool, not a manhood-measuring device. Focus on the gains rather than the absolute numbers.
Whew, okay. Back to Project Evo's baselining exercise.
We did four or five pulls and the peak numbers were about 320 lb-ft and 325 horsepower. I say "about" because the run-to-run variation floated a few hp or lb-ft higher or lower than these values. I'll post a representative dyno chart once my latptop starts cooperating.
Mike Welch, owner of Road Race Engineering, says that bone-stock Evo Xs typically generate about 250 horsepower on this dyno.
Factor in your favorite guesstimate for drivetrain loss based on all of this and we can see that we're roughly 65 horsepower shy of our power goal for Project Evo.
So, now what? With a decent complement of bolt-ons, the next logical step is cams. We talked with our friends at Cosworth in Torrance and they handed us a set of Cosworth MX1 cams, which Road Race Engineering graciously volunteered to install and re-tune for.
More to come.
Jason Kavanagh, Engineering Editor @ 15,851 miles.*
*we drove two miles on the dyno.
slickersdrip says:
12:44 PM, 01/23/09
Cosworth just handed you cams? I really, really need to get into automotive journalism.
firstwagon says:
01:03 PM, 01/23/09
Cool, I got right in the midle of the range.
http://blogs.edmunds.com/roadtests/2009/01/2008-mitsubishi-lancer-evolution-gsr-doing-the-math.html#comments
sealclubb3r says:
01:40 PM, 01/23/09
Oooo... What are y'all gonna do after installing the cams? Underdrive pulleys? Exhaust headers?
subytrojan says:
01:44 PM, 01/23/09
I'm personally not a fan of hub dynos. Why this instead of one with rollers?
I think drivetrain loss is less without the wheels on too, right?
Anyway, thanks for the update, Jay! Video would've been cool, too.
MS3lvr92 says:
07:12 PM, 01/23/09
Haha!! I knew it! I was only about 8 hp off. You're all like "No MS3lvr... your'e way to optimistic!" or "Get your head out of the clouds, there's no way this thing makes that much whp!"
subytrojan says:
07:38 PM, 01/23/09
MS3lvr92, most of our numbers were with wheels & tires on the car, sir.
joefrompa says:
11:02 AM, 01/26/09
Ok, I'm going to write about something that's been bothering me for quite some time:
Drivetrain parasitic loss
Nowadays, you turn left and right and everyone is saying "It only lost 10% from it's claimed crank HP, so this RWD car must be underrated"
"Drivetrain loss was only 15% to the wheels, so they must be underrating it from the factory"
Etc.
This bothers the hell out of me. I'm no mechanical engineer, nor expert in this area, but my understanding is that these are not linear equations.
I.e. If a 100 HP/TQ car loses 20% to the rear wheels, and you add another 100 HP/TQ to that car, the drivetrain did not suddenly require a doubling in effort to rotate it. The parasitic loss is mitigated as power goes up.
Similarly, again to my understanding, the momentum of rotating mass mitigates the parasitic losses as RPMs increase. So an application which builds peak power higher in the RPM band will have lower parasitic loss from peak crank HP to peak wheel HP.
Hence one of the reasons Hondas have always been known for low parasitic losses....because their engines develop peak power higher in the powerband, so the parasitic losses at those RPMs are less.
Anyway....been bothering me because I see Subaru owners with "20% parasitic losses stock" saying that their 300 whp applications mean they develop 360 crank HP....but that's not the case.
Joe
subytrojan says:
01:48 PM, 01/26/09
I usually assume 20-25% loss on AWD cars. If I remember correctly, stock MY2004-2007 STIs put out around 240 whp, 293 hp (SAE corrected for MY2007 iirc) at the crank, which is close to 20% loss.
joefrompa says:
10:39 AM, 01/28/09
Suby - I believe that if you keep upping the power of the STI, the drivetrain loss drops as a percentage. I don't believe it's a linear parasitic loss.
Joe