This sounds like a very interesting new craze! I'm about to install a voltage regulator on my 87Monte SS VAC sensor. Cost about $20 from DigiKey{LM317 voltage Reg} and other parts. It will boost the volts from the VAC so the ECM reads the correct fuel and spark map for a given throttle opening. My new cam only delivers 15" of VAC at idle and this should boost it up to the required volts.
I'll let ya know how it turns out!!

also......check-out http://www1.jaycar.com.au
Kits & Modules/automotive

 

Keep in mind that the ecm only reads up to +5V. Youll basically truncate the higher readings as teh ecm will cap it off at 5 volts. Providing some sort of offset, either electrically or electronically, can be of use as far as increasing table resolution, provided its with prom tuning.

 

I'm interested if that works. My 85 Grand Prix might benifit from something like that. Its just a dog compared to my toy.
Turning up the base timing doesn't help it.

 

This is where I got the info....but I haven't tested it yet. In the lab it worked by 12v supply and checking the output and it is adjustable, but I don't know if it's going to hold the VAC voltage at what I set it to{regulated}...or If it will be proportional to Vac output. I just want to add 2. volts to the sensor so the total at idle will be approx 4-5v @15" and as the throttle is opened the VAC drops off to 5" which should be aprox 2.volts. I plan to pull the sensor of the car and check it in the lab with VAC Pump.

Does this make any sense?


http://www.rightcoastcrawler.com/bil...EMAPSENSOR.HTM