PCM Diagnostics & Tuning - Help please...MAF, or MAF-less???




View Full Version : Help please...MAF, or MAF-less???


pbdrew15
04-17-2012, 05:01 PM
Guys, I'm going for a new tune setup as I've just moved from 800 feet elevation to 4200 feet. The car was previously tuned without a MAF on speed density tune using HP tuning. I bought the car that way. Now, I'm contemplating if a MAF tune will be a better way to go? Pros and cons to either way? And with my setup will a stock MAF be adequate? Or larger? If larger, which options are best and easiest? Car is an 01 Z06, 408 forged stroker. 11.5:1 CR, Dart 225 heads, 236/244 on 114lsa-.625/ .625 lift, 42lb injectors, FAST ported to 92 intake and throttle body. ARH long tubes, catless mids, stock ti exhaust for now.

Only problem currently is the elevation change and during idle it sits at 1000rpm and seems to after about 30 seconds of idle, switch into open or closed loop possibly and then runs EXTREMELY rich. So much that raw fuel can be seen out the exhaust and the smell. Did this even at 800feet. Any tuning guidance or input is def appreciated guys.


gectek
04-17-2012, 07:40 PM
I would use a MAF, but honestly it sounds like it never was tuned right in the beginning.

dodson55
04-17-2012, 09:00 PM
i would not use a maf just get a good tune on it and you will be fine


pbdrew15
04-17-2012, 09:59 PM
Lol so which is it....I know that a SD tune isn't going to adjust for altitude and temperature will it? I'm looking for some good tuners opinion and knowledge...

redtan
04-18-2012, 10:45 AM
Lol so which is it....I know that a SD tune isn't going to adjust for altitude and temperature will it? I'm looking for some good tuners opinion and knowledge...

It doesn't adjust for altitude, but it does adjust for temperature...that's why you have an IAT sensor which is used heavily in SD calculations.

So unless you plan on driving to the top of a mountain and then back down, I would not be scared to run an SD tune given the varying weather conditions.

Been running SD now for about 3 years and have gone through 90* humid summers and 10* bone dry winters with no issues and I always keep an eye on stuff with a dashhawk and wb installed.

SladeX
04-18-2012, 11:22 AM
An SD tune will just not be as efficient as a MAF tune when elevation changes come into play. The difference should be just barely noticable.

What it sounds like is that right now the tune is just off.

pbdrew15
04-18-2012, 04:03 PM
As a daily driver and the fact that I live at 4200 feet and within 100 miles in any direction the elevation can go up and down 1200 feet. Will SD be able to compensate for those type of changes? What if I want to drive the car to Florida or Cali, what then when it's at sea level with a SD setup that was tunes at 4200?