So after anxiously waiting for the results of the air filter shoot out I ended up getting the Perrin intake system. I am not tuned yet (was waiting to get the intake and datalog for Mellon) with TBE, test pipe, and now the intake, and was wonder what I should be looking for as far as A/F's? I'm using the AEM UEGO and will be getting my datalogs for Mellon ASAP to get my tune, I'm just don't want to be driving around with it TOO lean. Its late so I haven't driven it, will do tomorrow and post what I'm at, what do you guys think? Where should I be and at what point is it TOO lean?

 

ask mellon

 

youll probably go about .2-.3 leaner, and it should smooth out your AFR's on initial spool

cb

 

I actually emailed him right after posting this thread, looks like I'll be ok until I get my tune.

 

I was about .5+ leaner.

 

Was that 0.5 leaner compared to a high flow filter on the stock box? Or everything stock?

 

worry higher than 12

 

compared to stock airbox and blitz drop in.

 

I just did some runs and I'm at about mid 10's to low 11's. I'm surprised I'm still running that rich.

 

their very rich stock

 

was this from a stock tune? when i was stock my AFRs were <10:1 - 10.2:1 so that is about .5+

 

Yep, still on stock tune until I get my tune from Chris at Mellon. I've got the cables to hook up the AEM UEGO for datalogging, I just have to do that tonight then do some data runs.

I know Evo's are really rich stock but from what i had heard a intake, TBE, and test pipe would usually lean it out more, guess not, I'm still rich and running like a champ!

 

AEM UEGO is a good wideband. Self calibrating and so on. The onboard wideband on most dyno's are a bit more accurate. I never had a wideband before I did my build so I can't give you my two cents on stock block w/ mods and the A/F output. Watch your boost. Boost isn't everything but it sure will change you A/F.