doing the same thing to the exhaust cam you do to the intake cam brings the overlap back.

 

Ok finally got a handle on the swinging AFR problem that has been plaguing me. The solution is dubiously simple, make sure the MAF has a very smooth laminar flow to it and the car idles wonderful..

So I had the Buschur intake on it while the car had stock cams it was fine but when i put in the s1's suddenly I had issues. Solution was to put the stock intake tube on, I left the cone filter on the intake just FYI.

Now its idling very smooth with only minor deviations in the AFR.

I think if i was going to get a bigger than stock frame turbo (IE larger than FP Red) than i'm going to seriously entertain the idea of a speed density setup.

Hell i may do it anyways because it appears even undetectable changes in Maf readings via evoscan doesn't mean the flow is laminar. Having a speed denstiy setup will ensure that the Hz reading is totally smooth.

 

how much was your air fuel jumping? from like... 14.1 - 15.6? just wondering how much it was jumping.

or like 13.0 to 17.0

 

Or, eventually, someone could code up a 'maf-clamp' patch that could solve this problem and the stalling problem so common with larger cams/turbos/intakes that cause MAF reading errors.

I asked for this in a thread a while back, but with so many other things going on, no one has time to work on it.

 

Really i want that speed density setup ported to an Evo 8 rom

 

oh it was insane

it would start out at 14.7 then go radically lean slowing moving up to 18 or 19 afr and loping like a bastard. At the same time i could watch on my boost gauge the vacuum start to fall off as the idle stepper took over more and more then suddenly it would rev up to 1200 rpms and go to 12-11 AFR slowly backing down


now its like 14.5-15.5 totally a world apart

Edit:

Small update now that the car has run for awhile the idle swing is even less hovering easily around 14.5 - 15.1 usually staying in 14.7 most of the time.