In Reply to: Re: MAF vs AFM, again posted by Roops on May 16, 2001 at 05:12:52:
The next issue will have some E30 m3 dyno tests of things like different exhausts, JC chip, and the Split Second MAF conversion (www.splitsec.com).
I'm running an empty 3 inch pipe in place of my AFM. I'm using an AFM/link conversion to MAP sensor and throttle position sensor based fueling. Link Electrosystems. Lots of effort to wire and program via datalogging and spreadsheet work. Nearly 200 fuel map cells to program. I ran the car with both MAP and AFM to compare signals in order to get a perfect match. I can now remove the whole plenum if desired since the MAP signal is measured after the throttle blades.
The car is about 95% tuned and is gaining about 5-6 RWHP up high. More may be possible, and this was against a ported AFM. So far, the most noticeable changes are down low and at part throttle. Much smoother idle- best ever. Very crisp response. Very progressive throttle action. It seems like the good stuff begins about 500-1000 RPM sooner and the car is useable in the higher gears on the street more often - less need for downshifts in street driving. It can even happily run at or below 2000 RPM in 5th on side roads. This is with a JC chip, EVO intake cam... More midrange torque. Throttle blips are better too cuz the accel enrichment comes from changes in the TPS signal which is instant cuz it comes from a potentiometer on the throttle shaft and not from waiting for the Bosch flap to move.