MAP sensor feed location

[AdmiralSenn]

Hi guys. This is kind of a silly question given that my engine is already running and I'm finally in the tuning phase. Thing is, I'm still really new to huge portions of tuning theory, so please bear with my ignorance. I did search for this rather extensively but didn't find anything helpful.

I've got my MAP sensor reading off of an unused port on my manifold. It's working okay, but I'm not sure that it's optimal - I get lean spikes on acceleration at low RPM. I know I can tune around just about anything, but let me know what you think about this.

The port I'm using is at the far end of my manifold from the throttle bodies, and in a tiny little "dead spot" - the end of the runner above and slightly beyond the last runner on that side. However, there is another identical port at the other end - prior to all the runners, but still after the throttle bodies.

I'm attaching a picture (not my car but the same engine) to show where the ports are. I'm using port #1 at the top of the picture, the line I want to use is #2, right past the throttle bodies, which are also highlighted.

Would this be a better place for my signal? It seems to me that it'd read big changes better than where it is.

Thanks!

[Matt Cramer]

Port 2 might be better, at least in theory. In practice, the only way to know is to try. Usually the average MAP reading is the same but some locations have more noise.

[kritip]

The map sampling in MS2/EXTRA latest versions may well be worth a look at.