CAMARO6 - View Single Post - MSD Intake manifold makes engine runs richer ???

Nabush · 04-23-2018, 10:22 PM

Guys,

Strange....

I put my MSD Intake manifold this WE.

Before I had an AFE CAI and American Racing headers LT / X pipe with cats.

With this setup I had to add 5% more fuel at WOT to have a Lambda at 0.85-0.87. (12-12.2 AFR for E10 all pumps have so 14.1 stochio not 14.7)

I kept the same tune with the MSD....then I was running very rich (Lambda at 0.79 = 11.1 AFR for E10)

I had to go back to stock fuel trims to run back in the Lambda = 0.87 range...

I'm kind of surprised, I would have thought this IM would suck more air and then make the engine run leaner.... But when I look at my MAF mass air flow value i definitely see higher air volume through the rev range....

Can someone explain to me that ?

I'm new to tuning but this doesn't seem to make sense to me...

Thanks

04-23-2018, 10:22 PM	#1
Nabush Drives: 2017 C7 GS M7 / 2017 Camaro SS 1LE Join Date: Dec 2016 Location: Idaho Posts: 198	MSD Intake manifold makes engine runs richer ??? Guys, Strange.... I put my MSD Intake manifold this WE. Before I had an AFE CAI and American Racing headers LT / X pipe with cats. With this setup I had to add 5% more fuel at WOT to have a Lambda at 0.85-0.87. (12-12.2 AFR for E10 all pumps have so 14.1 stochio not 14.7) I kept the same tune with the MSD....then I was running very rich (Lambda at 0.79 = 11.1 AFR for E10) I had to go back to stock fuel trims to run back in the Lambda = 0.87 range... I'm kind of surprised, I would have thought this IM would suck more air and then make the engine run leaner.... But when I look at my MAF mass air flow value i definitely see higher air volume through the rev range.... Can someone explain to me that ? I'm new to tuning but this doesn't seem to make sense to me... Thanks