Brian will no doubt correct me, but if you are running too lean then your air/fuel ratio is too high. From reading the forced induction threads I think your A/F ratio for NA is about 14 and the FI guys generally seem to run their cars a bit richer to avoid nasty detonation, typically about 12. To adjust your fuelling you'll need a programmable ECU or a less flexible piggyback system, like the VAFC, and some dyno time to work out the proper fuelling at different rev points.

The thermostat etc is just controlling the coolant temperature Lee.

 

Leaning out is done by the ECU based on sensors from the intake and zorst IIRC.

 

Excuse my ignorance:

1 - Why could my car be running too lean for my setup?
2 - Why doe sthe Mugen ECU lean out the A/F ration?
3 - Would the J's racing ECU work well with my setup?

I would rather not go down the route of dyno tuning the car and would prefer a plug and play option.

Thanks.

 

AB, I can't answer those questions, but are you all J's racing kit? I know you've got an Amuse exhaust, what's the air intake, Mugen? The problem is you can't pick n mix all these "plug and play" mods and expect to get the best results without tuning. Having said that, I too am surprised that the relatively minor performance improvements from your mods would cause the car to run too lean, but Brian knows many tuned S2000s and so speaks from experience.

 

Thanks CA - I think you can pick and mix just like the J's started out by using the Mugen intake as do Amuse. The AMuse manifold is very similar in design to the mugen. I am just a bit worried about doing any damage to the car.

Got quite a different response from under the hood:

https://www.s2ki.com/forums/index.ph...&f=22&t=304605

 

AB, you misunderstand me (or more likely I'm not being clear ), you can pick n mix but you don't know quite what the result will be. Like I said above, I'm surprised too that the car would run too lean from just the mods you've done, but I've no experience of tuned cars

 

I actually read that the J's manifold would work well with the Mugen and Amuse dual but now I am a bit worried.

I haven't noticed any strange noises i.e. pinking.

I hope Brian can help clear my confusion.

 

 

The DV doesn't usually make a huge difference - do you know which one he's fitted?

Tell him to get it chipped then try it with you - I've tried the S against standard S3 and the S3 doesn't stand a chance, I reckon a chipped one would fair btter though!

 

Dreamer - from a standing start I agree but from a roll they aren't bad. He's getting a REVO chip next week - 265 or something.

Not sure if I mentioned it but all runs were with my roof down.