I have been suspicious of my car's performance ever since day one! On my first hill country "drive," 100 miles after break-in, the idle sounded rough. I took it in twice complaining that it idled like a sewing machine, not like a $40k sports car. They said it was normal.... no way!

Finally, I was angry and took it to a DYNO. Sure enough, compared to all the other dyno posts (thanks everyone), mine was LOW, esp under 6000RPMs. So I took it to an expert S2000 mechanic 200 miles away (in Houston), he said the valves were "unbelievably loose," and fixed it. Check out the results, before and after on each dyno printout:

Oh by the way, I think the break-in theories are true. I stayed under V-TEC until 550miles, then drove like an escaped mental patient for the next 5000 miles.

End result: 9000 miles, 205.5 HP stock, 210.7 HP stock w/airbox off and fan blowing in.

AWWW yeah....





So, if your car idles funny and your dyno looks like this, GET YOUR VALVES ADJUSTED

 

How was your car idling funny??

 

It literally sounded like a sewing machine. That is the best example. It sounded bad... but it sounds good now.

 

was your idle speed all whacky? like did your car nearly die and really run rough sometimes??

Was this covered as a warrantee item?

I'm wondering if this is something that I can check myself?

 

The idle speed was not wacky... It was really just the sound, and the butt-meter telling me that the power was not all there. In the intense Texas heat, with the A/C on, it would dip to 600RPM and shake a little, then recover. But the engine never stalled or died.

Now the heat is gone so I that problem hasn't shown up anymore. But, I think that is normal for some people and also could be related to the MAP sensor.

If you are unsure, my suggestion is to take your car to a dynomometer. If it looks like the low graphs in my pictures, it could very well be your valves. If not, well then I don't know what to tell you! Good luck!

 

hmmmm?

I have had the engine dip to like 600rpm and then also stall twice. I have heard that the MAP sensor is the culprit for a lot of this...but it sounds like I should also maybe have the valves checked

 

What's causing the big difference in torque in lower rpm ranges on Runs 3 & 6 and Runs 1 & 5 respectively. ( about 20 ft lbs difference ) Are these all run in the same gear or different gears?

BTW, thanks for the post. I don't remember valve adjustment being discussed here in the past. You can imagine that on a super high rpm engine that sees it often, this is a maintenance item that should be checked reasonably often.

 

Hummm I dont see how the car would have come with the valves THAT far off spec. Doesn't the book say to adjust them once at 100K only if they're noisy? I've adjusted valves on my B18C1 and the only difference was a slightly quieter engine.

 

That did seem like a large increase...note that he also had the airbox open and got higher hp...which seems different from what others have shown....due to hoter air mostly....

He may have had a HUGE fan forcing in air, I don't know..

 

[QUOTE]Originally posted by Rasputin314
[B]
Now the heat is gone so I that problem hasn't shown up anymore.