Map sensors functions??

[Turbocivic1]

Now from my reading on this site The impression I had of the map sensors is that one is for below boost and the other for on boost????

Well I did a little test to find out if this was true and I believe these are set to change from one to the other at a certain RPM in the computer???

What I did was put in the wastgate line 2 brass fittings that screw together and inside I put a spring and a ball bearing (also I made the wasgate pipe really long)
Now what this does is allow boost to build up real fast thus stopping wastgate creap and bringing on boost alot faster and being able to adjust the boost level. Anyway I set it so the boost would climb to almost 20psi
then took it for a drive.

Now with this setup the boost came on real strong at 2000rpm and it raced around to 20psi just below 2900rpm then as I got over 3200rpm I was thrown into my seat due to the boostcut/fuel cut. Now this to me sounds like the mapsensors are in use according to rpm not pressure before and on boost????

Anybody else can verify or prove me wrong????

[Michael]

Some computers have an overboost function built into them so the fuel cut will not be triggered straight away. Perhaps that is the explaination??