Thread: ls1 maf questions

I'm doing my N* tb swap tonight and I'm going to be running a LS1 maf with the setup. Is it a good idea to import in the LS1 tables to start with or just go from my modified stock ones? Do I need to change the "maf max negative/ positive" tables to correspond? And how about the "min/max maf frequency"?

the max and min should be the same for the ls1.
yes i would recommend swapping in a base Ls1 maf table as this will be closer then your modified l67 file.

Do you happen to know what the ls1 maf values are for min/ max? I don't have acsess to that info on my tuner

I dont have any bins with an LS1 maf. I think ZZP had a maf table listed but it could have been for their lq4 maf but i dont remember.

Yea, I've got the ls1 maf tables themselves. I'm looking for the corresponding tables.

If you are referring to the max and min hrz they are the same for almost all maf sensors for GM. Besides the maf table won't accept valuse above or below

Your talking about max/min fail freq? 10 hz and 13,500hz

Ok so leave the min, max stock then. How about the maf max negative/positive tables? Leave them too?

Ok, I've got the N* in but have a few small issue's. When you start the car it needs help initially to get it to idle, but after it's fine till the next start. The other thing is the PE mode is acting a little weird. I'm taking a wild guess there's more then the maf table that needs tweaking to make it run right. Also ,what about the maf max neg airflow change and maf max positive airflow change?

As for the PE, that will need to change with a N* as you get more air flow at lower throttles. Your previous pe throttle enable will be too high. As for max air flow change. I have seen some box tunes with it raised to about 30 some as in a DHP 1.5 starter file its 15 for all values. The min is left stock.

My PE is around 30% so I shouldn't be too far off. Could you explain what the max airflow change does? I'd like to understand it a little more then just the description dhp has.

I'm thinking of adjusting the max maf delta airflow too but not sure how much to increase it. I'm getting a lot of low rpm KR around 1/8 tps and then some up top. Most of my KR is after I let off the throttle...weird.

If you are seeing kr after letting off throttle your spark table may be commanding too much timing for the lower air mass.

Do you guys have dfco? Dfco can sometimes cause kr when you let off the throttle

Originally Posted by Z34Phoenix

If you are seeing kr after letting off throttle your spark table may be commanding too much timing for the lower air mass.

I ended up putting my timing tables back to stock and ran it, still seeing random quick .5-1 kr. My ltft's are a tad lean still but that shouldn't be causing low end kr like that. My PE is coming in quick and the AE has been raised up a good amount.

Originally Posted by 91parkave

Do you guys have dfco? Dfco can sometimes cause kr when you let off the throttle

In DHP no, but in tiny tuners it's available. The engine is leaning out some when letting off. Which table would I change to keep the fueling from leaning? Decel enlean vs tps?

Originally Posted by monte0

In DHP no, but in tiny tuners it's available. The engine is leaning out some when letting off. Which table would I change to keep the fueling from leaning? Decel enlean vs tps?

If it was hptuners I could look but I don't have tiny tuner on my platform...however I'd say lower the threshold that dfco comes in so when you let off the gas its not so sudden of a transition to possibly cause the kr if that makes sense

Ok, I'll check it out.

So got the car dialed in more and running good overall but still having weird low end KR plus also having issue's up top too. Timing in the last 4 cells have been pulled back .5-1* lower then stock along with my WOT timing maxing at 13*
The low end I will see random 3-5 KR at 10-15% throttle which is very weird. Plus I added a lot of fuel up top but doesn't seem to be quenching the KR till my narrow band starts going into the 990-1000 range (I know there not accurate but they will give you a ball park where you are). I pulled it back after that run to a more normal level 940-950 but KR persists.
I did notice my PE was coming in way to early. Sometimes it would show PE enabled around 1800-2000 rpm. My PE is set for 11.4 too
I've got my wideband but haven't had a chance to get it installed as of yet