Cams amd short term fuel trims

[03cobra#2]

I wanted to start up a discussion for thoes who have replaced the cams in their cars. How do your short term fuel trims look? I see a lot of recommendation to make sure you degree your cams. Most people say you need to degree cams to maximize the money spent on them.

If you don't degree them I can imagine you could have short term fuel trims off 20% between banks. When I did my cams I degreed them the best I could and I don't believe I have and exaust or vac leaks and my stft's are off 4-6% while diving around under part throttle load. When I free rev they are off a bit more.

Just wondering what people's stft's are with adaptive off (long term fuel trims off).

Sent from my Pixel 2 XL using Tapatalk

 

[gt347mustang]

4-6% isnt bad at all.

On the highway (fair amount of fuel flow) on a healthy engine i was seeing +/-2%. Injectors dont behave quite as good at lower fuel flow, like at idle, so i wouldnt be as concerned there.

 

[bigja01cobra]

How are they at idle? I remember reading somewhere that a high error at idle that goes away with rpm is typically indicative of an exhaust leak.

 

[03cobra#2]

Idle is like 4-5% difference. When you free rev and hold at like 1500,2000,2500 the difference grows. On the highway at steady speed of say 2000 rpm it's like 4-5% difference.

Sent from my Pixel 2 XL using Tapatalk

 

[gt347mustang]

Im sure its fine.

If you want to test out whether or not its the cams switch the o2's and injectors from bank to bank.

 

[03cobra#2]

I was thinking about that but at cruising they are pretty close. So I'm just gonna roll with it and continue my tune.

Sent from my Pixel 2 XL using Tapatalk

 

[KING_Asp]

I have cams in my car and my trims are within 2% of each other at idle and bounce from 4% to -2%. I have a lot of MAF though and I am in my last cell at idle. My cams are only stage 2 Comp cams off the shelf and I have them on a 112* intake 118* exhaust. Your trims sound like they will be just fine dude.

 

[03cobra#2]

I have cams in my car and my trims are within 2% of each other at idle and bounce from 4% to -2%. I have a lot of MAF though and I am in my last cell at idle. My cams are only stage 2 Comp cams off the shelf and I have them on a 112* intake 118* exhaust. Your trims sound like they will be just fine dude.

Great. Appreciate the input.

Sent from my Pixel 2 XL using Tapatalk