Quote Originally Posted by aaronng View Post
They don't make 1.8L motors revving to 12k because they need it to be reliable for up to over 200,000km, not having to be rebuilt every 20,000km.
That's exactly right, but they also have to be cost effective, therefore they do not put bigger throttle bodies on, or elaborate induction systems or 4:1 stainless steel extractors etc...
This is why we can improve on the performance of a car with bolt ons and i know from personal experience that a larger or bored out throttle body is definately a good candidate even on a stock engine.

I do not have a dyno sheet to prove this, as the only way i know it had a pick up was;
A) the way the car felt
B) in the diagnostic response i got from my emanage after fitting the T.B and taking her for a run!!