remove the pipes and then plugging the pipes then refit them to the intake and the valve, works a treat! no more waiting for the revs to slowly build up and then at 4500 it goes like a rocket, i can over-take quickly and smoothly blasting from 50-80 with no issues :D
So you're saying that to get the acis to always be in the same state it is above 4000rpm, you have to block the vacuum feed to the valve?
exactly that :) i tried various things first like connecting it directly to the inlet but i got no power past 4500rpm it was sluggish, i blocked the pipes now i just get what feels like a normal full revving engine.
Stuart Aspey
before i got my lexus (i wanted one for a year and a half) i knew it was the type of car to drink a bit of juice and i said i wanted to fit a diesel, even a 1.9 tdi from a vw golf would feel better to drive than the sluggish straight 6 24 valve and with better fuel consumption. even the old petrol redtop engine in the vauxhalls was only 4 cylinder and making the same bhp and used less fuel. why can't we have any of those options in standard form in the lexus is200!
i always felt that i had to struggle to get my car from A-B with the same amount of fuel as what used to be put in a mg-zr 120+ that we used to use, i noticed my foot was quite far to the floor in low rpm's but i wasn't really going anywhere fast but was probably using quite a bit of fuel even at cruising speed or just to even overtake a lorry was hard work and had to build up speed with my foot down quite hard before the car reached it's powerband at 4500rpm then it was safe to overtake. since bypassing the valve on the underside of the inlet manifold i no longer have this problem, i can be driving along in 4th gear at around 50 behind a lorry and then pushing my foot down the car picks up and goes and i'm hitting 80mph pretty sharpish! this is good for me and i feel it was the best FREE mod i've ever done to the lexus because i like power on tap and i feel i have more control over the power it gives rather than letting the car think for a minute and then get up and go. it may be a good idea for you to try this and just see if you save any fuel just driving normally the way that you do now, with maybe even less throttle opening to say 40% instead of 60%, i can't say if it will help you or not but it's up to you try it out, if it don't work just connect the pipes up again and you'll be back to exactly how it was before.