i see where maf tuning is more reliable for that kind of setup for a road race car, but for a wot blast, drag vehicle sd is fine. formula 1 are efi and not maf controlled.

 

Telling people who are new to tuning to ditch the maf and O2 is the wrong advice. I find most people ditch these items because they fail to learn them all the way. I have yet to get held up by the MAF in making power. Sure if the demands on the intake side are higher than the size maf you can buy, you can get a few HP out of it. But never assume that SD is the only way to go. And if you think you cant control fueling with a MAF, then you are wrong. I run an 18psi twin system on a MAF'd 3 bar setup with alky injection and I never have to change anything.

Rick

 

Since your local if you what to come check out a MAF tune and how to set one up just PM me and we can set up a time to meet. I have EFI Live and COS3 waiting to be uploaded...

 

You don't have to be in speed density to use the commanded fuel x map x rpm table. MAF airflow calculation works just fine with that table.

 

So you can run regular closed loop with COS3, that is what I was going to try, I really like that table!!!

 

I am an EFI NewB. I have learned to tune SD and have been tweaking my tune for several months now. Its fairly simple but I cant get my A/F Dead on. If fluctuates .75 lower and higher than my command A/F. I want a nice straight line like I see on everybody's Dyno Graphs I'm going back to MAF once I get a chance to read up on tuning with the MAF.

 

No, you have to be open loop, but setting any value in that table to stoich will go into semi-closed loop... STFT trimming will be active.

You don't have to disable the MAF to use it though, you can keep it active.

 

A custom operating system is not needed to enter speed Density mode contrary to what has been said. Nor do you need to remove any of your 02 sensors to enter Speed Density mode.

You will find a plethora of great information in this sticky http://www.hptuners.com/forum/showthread.php?t=8994

I recommend SD only for vehicles with large cams with overlap that creates drivability issues that cannot be fixed with the maf in place, I also recommend it for boosted applications making more boost than what the maf can read & fuel properly, whether thats 2 psi or 8psi depends on many variables.

Custom operating systems usually give you a few added tables & functionality of things like both spark tables, 1 VE table, etc but are definitely not needed to enter SD mode or even perform a speed density tune.

-Bill

 

Bill, I ordered HPT VCM std. yesterday, i didn't realize there was a real time option, seems to me that the real time option would make it easier to tune for a newbie, is that something you would agree to? and would it be possible for me to add it to what i've already ordered if that is a fact?

 

The real time option comes free with many of our custom OS's but is limited to mostly 99-04 calibrations, if you want to take advantage of it simple look under the OS tab in the editor file to view your options.

-Bill