I'm going to try and explain all the issues here so that you guys can get all of the details.

I was tuned previously on stock cams and had an a/f ratio of 14.50-15.2 at idle. I recently took my head off put new arp studs in and to install gsc s3 cams along with the 5041 kit.

After buttoning everything back up we turned teh crank by hand a few times and made sure the timing was correct and it was spot on!

Put it all back together and started the car and boy was it rich! At idle it is loping seriously and has an afr of about 10-11. It struggles to stay alive and i have to give it some gas to keep it going.

When it is revved to around 2-3k it makes a very loud rattling tapping noise on the intake side in the middle. I have since removed the valve cover and inspected everything. There are no unusual wear marks or anything out of the ordinary.

Did a compression test and the results were 110-120-120-110. Seems kind of low right?

Is it common for the a/f ratio to go rich after an s3 install?

Any idea on the noise? Could it be a lifter or two?

 

Did you bleed the lifters?

 

Are you sure you hooked all your vaccum hoses back up correctly? at idle you should stay close to 14.7 regardless as your in closed loop mode.

 

yes bled them dry and put them in empty. I'm on speed density and all lines are hooked up

 

I had that same noise after I installed my S2 cams. Come to find out it was my PCV valve. There's piece of metal that slides back and forth to open and close the valve, it will rattle around now due to the rough idle. Try holding it with ur fingers and it should mute the noise. Once u get tuned idle roughness will calm down and so should PCV rattling. Hope this helps.

 

I will look into the PVC valve tomorrow. Thanks.

 

Its not uncommon to see the AF at idle and through the rest of the revs change. The "lower" compression numbers are also normal, its due to the larger overlap with the S3, it bleeds a little bit of compression off. So all of the sounds normal.
The rattle is not normal. I would go thru and double check everything. It may just be the lifters not pumped up yet if they were bled all the way down. They can trap air and need to run at 2K+ RPM for a few minutes to pump up. Just depends on the car, they are all a little different and like to be a PITA

 

Thanks a lot Travis. It's great to have vendors chime in on here.
I'm planning on taking it apart tomorrow and rechecking everything