[robos4]

I know this is an old thread, very interesting.

I am nowhere near as technical (or smart) as you guys but I have to agree with Rotrex.

I have put my EVO X (4b11T) through it's paces over the last 6 years. It has had two engine builds, 4 different turbos etc etc. Now running Motec M150, 9174 twin EWG, 4" downpipe and exhaust valve, direct port meth (been using this for over 5 years).

We target 0.9 lambda (approx 13.2AFR) measured at the 02 sensor (and also in the exhaust pipe).

I run 1600cc/min in direct port plus 150cc pre turbo and 250cc pre throttle (6 jets). At 2.4bar it runs @ 100% flow (upgraded 300psi pump and line pressure >170psi under max flow).

We tried to add more fuel and make it richer but we lost power. It has been running 0.9 lambda for >4 years now and is very happy healthy engine.

This is 700awhp on mainline and full time attack car.

also I'm runnin 9.0:1 CR

edit: forgot to mention this is on pump fuel 98 and we also use det cans while tuning also. Worth mentioning we run 28deg timing and rev limit is 8,800rpm. we increased ignition timing to 30 degrees, it didn't make anymore power but it didn't knock also.