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Re:gm map sensor for high boost?

Hey I understand that See like this with a honda at 1 bar say yer at 9.62 (pm7 mugen bin) now say you want to hook up a gm 3 bar at 1 bar it sees 1.66v which on a honda would be about (---- math fart) 1/3rd so not only would you be lean you would be at about 24-25hg which i do not know that yer car would idle that lean.

Mind you this is all based off of 500rpm.

did i confuse myself???? ::)

Re:gm map sensor for high boost?

Quote:

Originally Posted by ZexRex

all a bigger map sensor does is send a different signal
Actually, it sends the same voltage (0-5v) but it's scaled differently. Say at 3.0 volts on a stock Honda MAP sensor, you're at ~1.3psi, on a GM MAP sensor at 3.0 volts you would be at ~21psi. Why? Because voltage increments are smaller with a GM 3bar MAP.

all it does is change the boost levels that are across the top of the graph in your zdyne/ghettodyne software.
And this is the most common misconception. Your fuel and ignition tables do not change. Using a different MAP sensor with a scaled voltage is similar to using an AFC (which also scales your voltage). Your fuel and ignition table column, and row increments stay exactly the same. You're just not going be using them in the same increments that you normally do. Which is why you need to retune them.

Re:gm map sensor for high boost?

Quote:

Originally Posted by ShadowRex

ok so Im right?

Heh, ya. ;)