I need advice and info. Car running lean after install

[ndubz]

I just installed my perrin TMIC with new samco piping and my samco turbo inlet. I took my car for a test drive with my friend and we read the live data on my accessport. Boost was fine at 18psi. It was running 90 degrees cruising at 80mph around 3k rpm. But the AFR under boost would now dip into the 11s and then climb up to the mid 13s (13.6 to be exact). Considering my car was tuned to run 11.1-11.3 AFR under boost so this is pretty lean. Yes im concerned. We checked for boost leaks, there were none, and we had pluged everything back in. I will check this all again, but is this normal for these mods to do?

prior my car was tuned by precision with EL headers, perrin Uppipe, TXS turboback exhaust (recently changed to the 3" RFL can muffler), and a short ram intake. tuned about 300awhp and 340awtq.

We did a Cobb AP dyno run today in 4th gear from 4250rpm to 6225rpm. with a weight of approximately 3700lbs (with me and my friend) the AP said it made 340awhp and 346awtq.

Now I know that that is in the real world and on a dyno it'd be less. but can someone on here (especially ray and ryan) help me make sense of all this. Cuz I had been told many times that this mod shouldnt need tuning. But i know there is something Ive got wrong here so someone please help me out here

thanks.

[Honest_Bob]

Reset the ecu.

[DaveSTi]

Sure you don't have a leak?

[rodknock02]

the problem is you are reading the slobb ap... You are relying off of the factory o2 sensor. You cannot go by that sensor. Dyno run at 4200 rpm??that isnt a dyno run.. thats a passing run. Try doing a run at 2k up to 7k.

Use a wideband o2 to read afrs.. not the factory 02

[ndubz]

all I know is the AP is saying 13.6 AFR. and its consistent in each gear. I looked and there was one small vacuum line that had come off on the intake manifold near the turbo outlet. I think that may be the cause. We had put it back on properly, it came off during the run. It comes off rather easy. Im gonna go out and test again in a few min. I'll post back then

[TROLL]

If you dont have a wideband, then you have no information to conclude anything from. The factory wideband will not display any useful information on a full throttle pull.

[Kir Diesel]

I think you need a new tune IMO.. As far as i know you cant just slap those parts on without a new tune.

[ndubz]

I just drove it with that slipping hose ziptied on and the AFRs were back at 11.1. the car felt alot stronger and smoother. I put a little silicone sealer on the tube so it will stay. Problem fixed..........I think. But Troll, can you give it like a week before you delete this thread. I just wanna be sure. Thanks

[rodknock02]

U NEED A REAL WIDEBAND !!!!! Pay the money and have someone tune ur car before u end up replaciing #4 haha

[enigma]

Yeah dude, I would definitly drop some money on a real wideband.

[cr8zyjap07]

you need a new tune. period.

[ndubz]

car seems to be running fine after I secured that hose. But what do you all mean? what should I get here and why? Please explain to me.

[TROLL]

we dont delete threads...

[enigma]

A wideband O2 sensor will give you a very accurate, consistent, and real-time view of what your a/f ratios are during any driving condition. They can tell you if you have a flat spot in your tune during normal driving, or if something has just gone wrong, rather than "lemme run home, grab my blah blah blah, hook it up to the computer and THEN see what the factory o2 has to say". Its one of those critical gauges that any modified turbo car should have.

[McNaSTI]

def getta good tune