Everyone of my customers running maggie 122's and 9lbs are still running maf's. With them we are running are MAF based controller.

Rodney

 

I'm running Garrett GT28 turbos.

 

Easy, just install a newer MAF and run a MAF based controller. You have the wiring there already. All a MAF needs needs to work is +12 and ground. And put it in the air stream.

Hope this helps,
Julio

 

in fact I still have Delphi 25168491 MAF in the inlet tube. The connector is just off. So you suggest I make connections to that pigtail so that the MAF control is separate from PCM and controls only the meth injection? I don't know how the MAF puts out Hz's when input is just alternator voltage..? How wide range would I have, I mean how up in the rpm range will I get proper readings? in this case PCM wouldn't be the restricting part.

 

The MAF puts out a frequency based on airflow past its element. What typically restricts how much is the size of the MAF itself and its element. The C5 doesnt have too much capability as it maxes out pretty early.. mid 500's to the tire. The latter model MAF's have a much higher capability as the size of the tube is greater.

While i'm not 110% sure on the following, someone here can correct me.. the max frequency is ~11000 hz as to what the PCM can see. I dont know if this limitation is just PCM related or MAF related. meaning I dont know for absolute certainty if the MAF hits 11,000 and stops.. or its just the pcm gets to 11,000 and stops reading higher.

So the GM MAF reads from 0-11,000 hz. On Fords it reads from 0-5 volts. The new 5.0 from Ford is now frequency. Guess someone is learning from the General.

Either way what your looking to do is read a signal from the MAF to run a controller. There is a company that sells a MAF frequency to voltage converter and it converts 6000 hz to 2.8volts and 11000 hz to 5volts. So its scaling is like a 2 bar map. 2 bar is 2.4 volts at 0 PSI, 5v at 15 PSI. 2.8 volts is approx 3 PSI. With a PD blower you start spraying at 5500-6000 HZ and let it ramp up from there. As most of the progressive controllers on the market are voltage based 0-5v. Using a MAF setup you can even use injection on an NA setup as the MAF is the closes thing to "LOAD reading" you'll get. The reason 2 bar, 2.5 bar, 3 bar MAP's are used is because of MAF limitations(unable to read/pegged) on the majority of kits.

Think of it like an 85 MPH speedometer= C5 MAF. On a car that runs 100+ MPH.

All your MAF needs is the +12 and ground on the factory plug.. then run the signal wire to the MAF freq-volt converter to drive the alky/meth controller. Has nothing to do with the onboard PCM.

Hope this helps.

 

i would most definitely install meth.... the resulting lower iat's will a) surpress detonation b) added octane will help surpress detonation as well..... i generally dont view meth as a power adder pursay but it will add power and safety if tuned correctly...