Spark timing cylinder air mas g/cyl. My truck vs friends.

[Nastruck]

Started tuning my buddies truck the other day and noticed my cylinder air mas g/cyl doubles his truck at wot. Only real reason I could assume why would be he has factory manifolds and I have long tubes causing this restriction? I can post both tunes and both data logs. My truck wot running across .80-.92 g/cyl and his truck only .44-.48 g/cyl. Both are running SD. Mine is open loop his is closed loop

My truck Lq4/243 tsp 228r 112lsa. Long tubes, catless, intake, and electric fans

his truck awd Silverado SS Lq9/241 23x/23x 110lsa, intake, catless, electric fans.

[cesar]

do you have modified injector data? or any form of atermarket injectors

[POWERZONE]

I would need to see your scanner configuration.

Taking a blind guess, I bet when you are logging his tune and he is in SD, MAF(SAE) is being logged.

[POWERZONE]

I would need to see your scanner configuration.

Taking a blind guess, I bet when you are logging his tune and he is in SD, MAF(SAE) PID is being used and logged.

[Nastruck]

My truck does have 36lb flex fuel injector swap. His is stock fuel system. His tune I did not remove maf from the data list just zeroed the maf table. My truck is the same config except I used wideband on mine. Just curious if that's signs of a restriction. I'll upload each config and tune/log when I'm home

[POWERZONE]

My truck does have 36lb flex fuel injector swap. His is stock fuel system. His tune I did not remove maf from the data list just zeroed the maf table. My truck is the same config except I used wideband on mine. Just curious if that's signs of a restriction

This occurs when trying to log a cars/truck that is in SD but the PCM still tries to calculate cylinder air mas from the bogus MAF reading.

Next time you log his truck, in your scanner, remove the MAF(SAE) pid and see what you get.

Try to remove the pid first before changing anything else on the car or tune.

[Nastruck]

Thanks for the advice. I'll give it a shot next time I get a hold of it.

[Nastruck]

You are bound to be correct. Tho both trucks still have the Maf (sae) pid both trucks g/cyl pid are in the 80-85 range in pid table display. Just not the same in the Histogram table for the SS truck. I'm going to remove the MAF SAE pid in both vehicles for now on. Thanks for the help again

[POWERZONE]

You are bound to be correct. Tho both trucks still have the Maf (sae) pid both trucks g/cyl pid are in the 80-85 range in pid table display. Just not the same in the Histogram table for the SS truck. I'm going to remove the MAF SAE pid in both vehicles for now on. Thanks for the help again

Only remove it for the truck that is in SD. If you are still using it for your truck that still uses a MAF sensor, you are fine.

[Nastruck]

I see what I did. The log of my truck I compared to was a night that I was actually playing with tuning the MAF. I usually stay in SD. My normal SD tune shows the same low G/CYL as the SS. So I need to remove MAF sae PID from both vehicles and rescan.

[POWERZONE]

I see what I did. The log of my truck I compared to was a night that I was actually playing with tuning the MAF. I usually stay in SD. My normal SD tune shows the same low G/CYL as the SS. So I need to remove MAF sae PID from both vehicles and rescan.

When I tune VE, I remove the pid in my configuraton for tuning VE.