S2000 Power

Author
Discussion

Jockstar205

Original Poster:

330 posts

197 months

Monday 8th September 2008
quotequote all
I currently own a phase 1 S2000 with an AEM V2 air filter system. The engine isn't modified in any other way.

Recently I got the car put on the rollers and it made 202.9 @ roughly 7750rpm and 146 lb/ft @ 5800rpm. Both figures are down on what Honda states the engine produces.

Did Honda come up with these figures on a bench instead of when the engine was fitted to an actual car? Has anyone else dyno'd their S2000 in standard trim to find out it had less power?

Engine drives fine, just a little confused.

normalbloke

7,714 posts

226 months

Monday 8th September 2008
quotequote all
Honda would have quoted figures at the flywheel,I assume your figures have been produced for "at the wheels" ie allowing for tranmission and differential losses etc.


Or you bought a knacker....

Jockstar205

Original Poster:

330 posts

197 months

Monday 8th September 2008
quotequote all
No that's flywheel figures and from another video on you tube I see I'm not the only one. I'm not convinced they make 237.

Anyone else rollered there S2K? If it was a knacker I think I'd notice driving it but thanks for that.

Dracoro

8,798 posts

252 months

Monday 8th September 2008
quotequote all
Also RR are notoriously inaccurate as a guide to actual power output. For one, the figures have a certain element of "guesstimation" involved.

However, they are useful when tuning/modding your car to get before/after figures etc.

FWIW, most RRs I see people posting on s2ki come up at around 200bhp+ (at wheels) which works out to 235bhp if a 17.5% losses is used.

Edited by Dracoro on Monday 8th September 21:46

Jockstar205

Original Poster:

330 posts

197 months

Monday 8th September 2008
quotequote all
Aye I'm not entirely convinced the place I went to can be trusted, I've been doing a bit of reading up and I've not got a huge amount of faith in that reading anymore, but like you say it's not an exact science.

Dracoro

8,798 posts

252 months

Monday 8th September 2008
quotequote all
I reckon you've been quoted at the wheels power, not flywheel.

If flywheel, then that'd mean it would be about 165 at the wheels....

Jockstar205

Original Poster:

330 posts

197 months

Monday 8th September 2008
quotequote all
The operator defo said flywheel, that's why I questioned him about it.

I'll get it done at GMC motorsport when the Pug gets mapped for it's new engine.

StarTrack

5 posts

194 months

Tuesday 9th September 2008
quotequote all
In my experience, I have never seen lighlty modded s2000 doing 240bhp on a dyno that could be trusted. However if you do 200 flywheel then something is wrong.

If you want a dyno that is accurate (ie not over enthusiastic nor pessimistic) have a look at Surrey Rolling road.

MrFlibbles

7,711 posts

290 months

Tuesday 9th September 2008
quotequote all
Give them a call and ask them for the figure at the wheels and what correction factor they used.

Have you "compared" the performance of your car against any other S2k's or indeed anything else?

If it was actually only putting out 200bhp @ the fly you'd be in CTR territory, whereas for reference I absolutely pulled an FN2 CTR's pants down a few days ago (Mines standard except for a cat back exhuast)

Jockstar205

Original Poster:

330 posts

197 months

Tuesday 9th September 2008
quotequote all
I've never driven another S2000 nor raced one so I can't say, nor has anyone in a Civic Type R raced me. So well behaved lol.

normalbloke

7,714 posts

226 months

Tuesday 9th September 2008
quotequote all
Jockstar205 said:
No that's flywheel figures and from another video on you tube I see I'm not the only one. I'm not convinced they make 237.

Anyone else rollered there S2K? If it was a knacker I think I'd notice driving it but thanks for that.
You're welcome sir..

Also, isn't the quoted peak horsepower at 8300rpm or thereabouts? ?Perhaps you had an old Mintoe stuck under the throttle pedal?

MrFlibbles

7,711 posts

290 months

Tuesday 9th September 2008
quotequote all
Jockstar205 said:
I've never driven another S2000 nor raced one so I can't say, nor has anyone in a Civic Type R raced me. So well behaved lol.
Not racing, comparing!

haggishunter

1,315 posts

250 months

Tuesday 9th September 2008
quotequote all
If I had something like that under the pedal I'd have scoffed it!

mikey k

13,014 posts

223 months

Wednesday 10th September 2008
quotequote all
I'm on my fourth S
Two of my stock ones gave ~195WHP or 237.8BHP @ 18% losses.
My current one gives 343WHP or 418BHP wink

Edited by mikey k on Wednesday 10th September 20:32

Jockstar205

Original Poster:

330 posts

197 months

Thursday 11th September 2008
quotequote all
Ok well had the S2000 on the rollers again but this time at Star Performance. Results are as follows :

245.5 bhp @ the flywheel
185.0 bhp @ the wheels
Drag = 57.0 bhp

Max power @ 111mph or 8590rpm in 4th gear.

Max Torque @ 98mph or 7540rpm (152lb/ft @ flywheel)

Max speed in 4th = 116mph @ 8920rpm

Air pressure = 994 mbar
Air Temperature = 17 degrees (although the operator said it might have been chilled as lows as 13 degrees)

Bascially the difference between Star and Hypertech that jumped out at me is their 2 huge fans which are worth 5 grand each and they take air from outside the premises not inside.

When he fired them up they sounded like turbines. At Hypertech they closed my bonnet and pointed the hand held fan at my filter behind the front bumper. Not quite the same!

At Star they also left my bonnet open. I believe the difference in result is down to more efficient cooling methods.

Anyway I'm happier now as you can imagine.

Holst

2,468 posts

228 months

Thursday 11th September 2008
quotequote all
Do you know the at the wheels figure that the first place recorded or did they just tell you the estimated flywheel figure.

Trying to work out the flywheel BHP from the power at the wheels leads to a big ammount of innacuracy.

The only usefull way to use a dyno at the wheels is to compare two cars that should be the same (go to a club dyno day)
They are not usefull for comparing your car to the manufactuers figures, or your car to another tested on a different dyno (or even the same dyno on a different day)


Uncle John

4,503 posts

198 months

Friday 12th September 2008
quotequote all
Another vote for Surrey Rolling Road, a friend from Surrey Scoobies swears by them.

henpecked

110 posts

229 months

Saturday 13th September 2008
quotequote all
I had mine on Dastek in Fife, made 234.5 at the wheels@ 8903rpm and 142.5lbsft, 191.2 at the flywheel, bar was 1004.m Stock bar a K&N filter insert.

Edited by henpecked on Saturday 13th September 21:07