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2k4 Honda S2000: 245HP... TO THE WHEELS?

Flyermax2k3

Diamond Member
Mar 1, 2003
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The graph clearly states "@ the flywheel". That's *not* the wheels ;) Most S2k's I've seen dyno right around 200HP to the wheels.
 

RagingBITCH

Lifer
Sep 27, 2003
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Originally posted by: Flyermax2k3
The graph clearly states "@ the flywheel". That's *not* the wheels ;) Most S2k's I've seen dyno right around 200HP to the wheels.
Well, its taken us two months to find a broken in consumer car (read bought at a dealer by a normal consumer) that would take us up on our offer of a free dyno test. Many thanks to "Backcracker" of S2Ki.com fame (and many Orange County parties) for letting TOV test his car.

Since the substitution of a new ECU and retest of the press car was not enough to completely dispel the rumors of a ringer, TOV put Backcracker's car on the Dynapack at Church Automotive Testing to see if it would produce anywhere close to the hp of the press car. Just in case you'd forgotten, or skipped directly to this page, the press car put down 243 whp vs. 212-220 whp for the previous year S2000s (the 00-01's put down 212-214, the 02-03's 215-220).

With the beautiful white on tan 04 bolted to the dyno, intake and coolant temps were checked, 4th gear was engaged and 2 passes were made. The results? 245 and 243 whp. All with about 700 miles on the odometer.
The description says WHP. Why would a dyno meter software that is tracking actual horsepower at the wheels tack on the 10-15% drivetrain loss?
 
Jan 31, 2002
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Originally posted by: RagingBITCH
The description says WHP. Why would a dyno meter software that is tracking actual horsepower at the wheels tack on the 10-15% drivetrain loss?
Yeah, I was kinda confused by that. I don't see how the dyno software could accurately factor in the drivetrain loss. This is the 04 S2K too, so they might have done some serious reworking. :p

- M4H
 

Zenmervolt

Elite member
Oct 22, 2000
24,510
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Originally posted by: MercenaryForHire
I don't see how the dyno software could accurately factor in the drivetrain loss.
They do a couple "coast down" tests with the transmission in gear but the clutch disengaged and they measure braking force of the transmission on the wheels.

ZV
 

Vortex22

Diamond Member
Sep 6, 2000
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The description says WHP. Why would a dyno meter software that is tracking actual horsepower at the wheels tack on the 10-15% drivetrain loss?
Huh? Where does it say the software added 10-15%?

 

TekViper

Senior member
Jul 1, 2001
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not added, subtracted to account for hp lost in the drivetrain by the time it gets to the ground.
 

Zenmervolt

Elite member
Oct 22, 2000
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Originally posted by: Vortex22
The description says WHP. Why would a dyno meter software that is tracking actual horsepower at the wheels tack on the 10-15% drivetrain loss?
Huh? Where does it say the software added 10-15%?
Because, if an engine is putting out 100 HP to the wheels, it typically puts out 110 to 115 HP at the flywheel. Many dynometers account for the HP that is "stolen" by the drivetrain to give the higher Flywheel HP number.

ZV
 

Zenmervolt

Elite member
Oct 22, 2000
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Originally posted by: TekViper
not added, subtracted to account for hp lost in the drivetrain by the time it gets to the ground.
If the dyno is taking its reading at the wheel (as it is doing) then it adds HP to account for drivetrain loss in order to give an accurate measure of flywheel HP.

ZV
 

RagingBITCH

Lifer
Sep 27, 2003
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Originally posted by: Vortex22
The description says WHP. Why would a dyno meter software that is tracking actual horsepower at the wheels tack on the 10-15% drivetrain loss?
Huh? Where does it say the software added 10-15%?
That was in reference to what Flyer said. You and the article both stated at the wheels, he said the graphs clearly state "Flywheel". I was making a comment about why it would show it at the flywheel as opposed to at the wheel. (10-15% is just a guestimate about the usual difference in WHP and flywheel HP)
 

Vortex22

Diamond Member
Sep 6, 2000
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Originally posted by: Zenmervolt
Originally posted by: Vortex22
The description says WHP. Why would a dyno meter software that is tracking actual horsepower at the wheels tack on the 10-15% drivetrain loss?
Huh? Where does it say the software added 10-15%?
Because, if an engine is putting out 100 HP to the wheels, it typically puts out 110 to 115 HP at the flywheel. Many dynometers account for the HP that is "stolen" by the drivetrain to give the higher Flywheel HP number.

ZV

I understand that, but where on that page does it say that dyno they used was indeed adding HP to account for the drivetrain loss? I was under the assumption that those numbers were the actual HP at the wheels.
 

Zenmervolt

Elite member
Oct 22, 2000
24,510
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Originally posted by: Vortex22
Originally posted by: Zenmervolt
Originally posted by: Vortex22
The description says WHP. Why would a dyno meter software that is tracking actual horsepower at the wheels tack on the 10-15% drivetrain loss?
Huh? Where does it say the software added 10-15%?
Because, if an engine is putting out 100 HP to the wheels, it typically puts out 110 to 115 HP at the flywheel. Many dynometers account for the HP that is "stolen" by the drivetrain to give the higher Flywheel HP number.

ZV
I understand that, but where on that page does it say that dyno they used was indeed adding HP to account for the drivetrain loss? I was under the assumption that those numbers were the actual HP at the wheels.
Read the top of the graph. It very clearly says "Flywheel Horsepower".

ZV
 

Flyermax2k3

Diamond Member
Mar 1, 2003
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Originally posted by: Vortex22
Originally posted by: Zenmervolt
Originally posted by: Vortex22
The description says WHP. Why would a dyno meter software that is tracking actual horsepower at the wheels tack on the 10-15% drivetrain loss?
Huh? Where does it say the software added 10-15%?
Because, if an engine is putting out 100 HP to the wheels, it typically puts out 110 to 115 HP at the flywheel. Many dynometers account for the HP that is "stolen" by the drivetrain to give the higher Flywheel HP number.

ZV

I understand that, but where on that page does it say that dyno they used was indeed adding HP to account for the drivetrain loss? I was under the assumption that those numbers were the actual HP at the wheels.
Let me try and explain this. The HP was measured at the wheel (hub assembly, actually) and then corrected via a formula for flywheel HP. Get it? They measured at the "wheel" but gave flywheel power. That's just the way the dynamometer they used works.
On a side-note: dynapacks are notorious for giving "high" readings ;) Just keep that in mind when looking at these numbers.
 

Zenmervolt

Elite member
Oct 22, 2000
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Originally posted by: WinkOsmosis
I wasn't implying that you actually had a Buick. I was pointing out the benefit of having the powerband stretching to such high rpm.
I love the S2000, but the powerband does not "stretch" to such high RPM, it (for all intents and purposes) does not exist until such high RPM. It's a lot of fun to play with a high-revving engine, but those engines are gutless unless one revs the piss out of them. Quite honestly I'll take the powerband from the 281 CID (4.6 litre) 32V V8 in my Mark VIII any day. It has power everywhere, it'll pull like a freight train from idle to redline. Makes it a little hard to modulate in the snow, but it's so nice to know that the engine can't be caught flat-footed.

ZV
 

ElFenix

Elite Member
Super Moderator
Mar 20, 2000
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Originally posted by: WinkOsmosis
Originally posted by: vi_edit
Originally posted by: WinkOsmosis
Originally posted by: vi_edit
LOL@105HP@4000RPM
And it still has more area under its hp curve than your Buick.
Since when did Buick start offering 30 valve V6's?
I wasn't implying that you actually had a Buick. I was pointing out the benefit of having the powerband stretching to such high rpm.
it doesn't stretch there, that is the only place it exsits!
 

Zenmervolt

Elite member
Oct 22, 2000
24,510
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Originally posted by: ElFenix
Originally posted by: WinkOsmosis
Originally posted by: vi_edit
Originally posted by: WinkOsmosis
Originally posted by: vi_edit
LOL@105HP@4000RPM
And it still has more area under its hp curve than your Buick.
Since when did Buick start offering 30 valve V6's?
I wasn't implying that you actually had a Buick. I was pointing out the benefit of having the powerband stretching to such high rpm.
it doesn't stretch there, that is the only place it exsits!
Oh, you're one minute too late. :p

ZV
 

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