Anyone with FTRA (or other sealed ram air) and ported stock MAF?
12-18-2001, 08:22 PM
#1
Anyone with FTRA (or other sealed ram air) and ported stock MAF? If you've got this combo, how are your O2s as you go down the track?
My problem was:
At the start of the 1/4, I was getting .935-.955 O2 readings. By the end of the run, it had dropped down to .870's, and a few degrees of KR (none at the beginning).
My theory:
The ram air is forcing air into the intake as the speeds increase. It's pushing more air past the MAF, but since the screen is out, it isn't getting a very accurate reading, and keeps leaning and leaning out as the car goes faster (more air being rammed in).
I put the stock MAF ends back on for now (track is closed) and have tuned my O2s back down with a MAFT. I'm still not getting the level of timing I was with the ported ends though (street testing). With the ported ends, I was getting up to 30.5 degrees of timing at WOT (6000rpm). Even with 3 degrees of knock in 3rd gear, it was getting up to 28.5 degrees at 6000rpm.
So, does anyone else have this problem? is my theory sound? If so, I will probably switch to an 85mm screened MAF, for extra flow while maintaining an accurate reading.
Just looking for people who have had the same issues and some possible solutions, or maybe telling me that I'm smokin some of my namesake <img src="gr_stretch.gif" border="0">
Dope
My problem was:
At the start of the 1/4, I was getting .935-.955 O2 readings. By the end of the run, it had dropped down to .870's, and a few degrees of KR (none at the beginning).
My theory:
The ram air is forcing air into the intake as the speeds increase. It's pushing more air past the MAF, but since the screen is out, it isn't getting a very accurate reading, and keeps leaning and leaning out as the car goes faster (more air being rammed in).
I put the stock MAF ends back on for now (track is closed) and have tuned my O2s back down with a MAFT. I'm still not getting the level of timing I was with the ported ends though (street testing). With the ported ends, I was getting up to 30.5 degrees of timing at WOT (6000rpm). Even with 3 degrees of knock in 3rd gear, it was getting up to 28.5 degrees at 6000rpm.
So, does anyone else have this problem? is my theory sound? If so, I will probably switch to an 85mm screened MAF, for extra flow while maintaining an accurate reading.
Just looking for people who have had the same issues and some possible solutions, or maybe telling me that I'm smokin some of my namesake <img src="gr_stretch.gif" border="0">
Dope
