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ST
11-09-2006, 03:47 PM
Many know that the typical Evo IX typically to the tune of 235whp on the Mustang Dyno on average. Supposedly this translates to the 286bhp rating by Mitsu, equating ~ to a an unbelievable 18% parasitic drivetrain loss. Why unbelievable? Well because most w/ an AWD setup, you'd expect much more loss through the transfer cases, half shafts, etc. Most typical RWD vehicles loss about 25% w/ a simple rear driveshaft layout.

The reason why i bring this up is because the other week on the EIP dyno, a newer 333bhp rated e46 M3 was dyno tested and read only around 235whp, equating to ~29% drivetrain loss. Another way of extrapolating bhp of course is via ETs or more specifically trap speeds through the 1320. Assuming a good driver, I think average times for a stock Evo IX are around 13.0 sec @ 108mph, which after some calculations is around 300bhp (through ETs) or 325bhp (trap speeds), when considering the 3300lb weight. This figure more would more roughly calculate out to the 235whp dyno figures seen for a more reasonable 28% drivetrain parasitic loss.

I know back my Supra TT days, everyone KNEW the stoc 320bhp rating was just a sham for insurance purposes as they usually dyno 305whp stock! Now I haven't read much onto the Evo's and the 4G63s, but it seems they are well underated as well. Thoughts, comments, critiques welcome.....

masurie
11-09-2006, 03:55 PM
+1 on the 2006 m3,

one of my friend just got one and he already upgraded into eisennmann exhaust, i tried it and it is a bit slower than my car, we actually tested it (not exactly racing :lol:) and my evo got about 3/4 lenght on his car and we slowed down after reaching 90ish (its on 40mph limit)...

so ya evo for sure is underrated......

vtluu
11-09-2006, 03:58 PM
Evo's engine power is understated, this goes back to when cars in Japan were "limited" to 276bhp (or something like that), so they would sell cars with a stated bhp of 276. The Evo 8 probably makes somewhere north of 300 bhp, the Evo 9 a bit more than that.

ST
11-09-2006, 04:05 PM
Evo's engine power is understated, this goes back to when cars in Japan were "limited" to 276bhp (or something like that), so they would sell cars with a stated bhp of 276. The Evo 8 probably makes somewhere north of 300 bhp, the Evo 9 a bit more than that.


I realize that old gentlemen's agreement to limit to 276bhp in Japan, but some vehicles were actually rated as such. For instance the JDM Supra TT was really around 290bhp, because they utilized smaller turbos for quicker spoolup, as opposed to American market, due to our fascination with bhp and highways.

Since the Japan's mfg. gentleman's agreement has been pretty much forsaken nowadays, there is really no need to underate the cars, especially when in the hp hungry american market, except for maybe insurance purposes. In fact, many cars are actually overrated, hence the new SAE bhp rating requirement recently enacted on many newer cars that has revised many numbers significantly. This is not to even mention the Mazda fiasco that has ensued with the Miatas, RX8's, etc. that has left the company in a quandry over their stated bhp figures.

I wonder if this stipulation is just somewhat conservatism by Mitsu and to insure the Evo is left in a lower insurance category (i believe the cutoff is around 300bhp, correct me if im wrong), and somewhat to play a marketing game with the likes of the Subbies....

earlyapex1
11-09-2006, 04:19 PM
Assuming a good driver, I think average times for a stock Evo IX are around 13.0 sec @ 108mph,


Crack smoker! Show me someone trapping 108 in a bone stock IX!

SilverStreak
11-09-2006, 04:27 PM
...and somewhat to play a marketing game with the likes of the Subbies....


I know that some companies in the past ie Toyota and Mazda have overrated their cars and the PR dept had been forced to re-do the numbers much to their customers dismay. Â*I think Subaru has done something similar...I remember reading their new A-line STI model had sub 300bhp specs.

There has been a bit of marketing battling going on. Â*Supposedly Subaru waited until the unveiling of the EvoVIII to see its specs...then released their own STI with higher specs on paper. Â*They are rumored to have also prepared two separate spec sheets one with similar numbers to the Evo, and one with drastically higher numbers depending on what the Evo's output was.

After much hype...the Evo still narrowly won the battle according to most mags.

ST
11-09-2006, 04:33 PM
Crack smoker! Show me someone trapping 108 in a bone stock IX!


Alright, maybe thats a bit more optimistic... so let's make that around 105-106mph stock trap speeds...this would place it around 307bhp...still less drivetrain loss than i would imagine...

MarkSAE
11-09-2006, 04:41 PM
No way stock IX's are trapping 105-106.. I think most of them trap in the 102 mph range.

ST
11-09-2006, 04:50 PM
No way stock IX's are trapping 105-106.. I think most of them trap in the 102 mph range.


http://forums.evolutionm.net/forumdisplay.php?f=16

MarkSAE
11-09-2006, 05:01 PM
ST, on our gas I mean. The 93-94 octane those east coast guys get is like race gas compared to our gas.

BigEd925
11-09-2006, 05:02 PM
my highest trap speed was 102, people have gotten up to 108 on 100octane.

ST
11-09-2006, 05:04 PM
ST, on our gas I mean. The 93-94 octane those east coast guys get is like race gas compared to our gas.


i c where ur coming from...i was just saying that based on evom east coast numbers =(

ST
11-09-2006, 05:09 PM
my highest trap speed was 102, people have gotten up to 108 on 100octane.


hmm i think therein lies one of the reasons for the low rating. w/ 102 trap speeds, you're looking at around 275ish bhp figures at the crank...since the gas quality varies within the country, some of the conservatism in hp figures is to go by the lowest rating possible on worst case scenario working condition...91 octane, in the desert, etc.

MarkSAE
11-09-2006, 05:15 PM
ST, I did some comparisons with dyno #s and 1/4 traps a while back.

http://www.norcalevo.net/index.php?option=com_smf&Itemid=2&topic=5463.0

ST
11-09-2006, 05:33 PM
ST, I did some comparisons with dyno #s and 1/4 traps a while back.

http://www.norcalevo.net/index.php?option=com_smf&Itemid=2&topic=5463.0


very interesting mark... your whp figures look great, yet your trap speed times and ets were pretty average (lower actually)...the descrepency doesnt make much sense, other than bad driver/launch?

MarkSAE
11-09-2006, 05:39 PM
It's probably my crappy driving. I'm not the quickest shifter either.

ST
11-09-2006, 05:56 PM
It's probably my crappy driving. I'm not the quickest shifter either.


i don't blame you, i've ham fisted the shifter a few times...Andy (Speed Element) on the other hand is one helluva driver going through the gears! Has anyone besides Racer1 (Sean) gone in the 11's here (on the stock turbo)?

earlyapex1
11-09-2006, 05:58 PM
I need to bring my car to the strip. I haven't drag raced in over 7 yrs though. :-O

MarkSAE
11-09-2006, 06:05 PM
Why don't you G-tech it? ;)

whtrice
11-09-2006, 06:18 PM
Let's go bowling!!!!

I need to bring my car to the strip. I haven't drag raced in over 7 yrs though. :-O

ST
11-09-2006, 06:27 PM
Let's go bowling!!!!

I need to bring my car to the strip. I haven't drag raced in over 7 yrs though. :-O



OT - you're one day too late, as the SJ Meet folks just went bowling where our UCB bowled a 216! O.o

Lurk
11-16-2006, 03:05 PM
I hit a 12.6 @ 116mph before @ Infineon, slow ET due to the fact that I didnt launch too well. But I ran that time and trap speed with the stock turbo.