They can auto adjus it will send your LTFT either positive or negative, you just run the risk of the ecu going I don't know what's going on I'm done adjust fuel trims at wot and you spike lean. The ecu is maf based, GM spent some time dialing in the maf freq airflow table for the stock intake and it's turbulence, throw a different intake on there and it needs changed.

 

Fuel trims are the adjustment sir. Your AFR will be where it needs to be but when the MAF is inserted into a larger intake pipe (most try to mimic the stock pipe diameter), your programmed measurement of airflow will be off and cause Fuel trim creep. Basically overtime your fuel trims will start heading in one direction (Negative or Positive) depends on how the MAF is seeing the airflow/ turbulence.

Eventually once the fuel trim reaches ~ + or - 20 LTFT (long term fuel trim), the car throws a code. a -20 LTFT is the same as saying your car needs to pull back 20% of the fuel its normally adding (running rich) in order to achieve stoichiometric air fuel ratio. A +20 LTFT would mean the car needs to add 20% more fuel than normal (running lean).

The K&N is a pretty good intake in that the MAF placement is pretty close to stock and the tube diameter is close to stock. Rotating the filter is a bonus for trim adjustments. Its been discovered that different orientations of the filter lead to different trims in the fuel. Theres a few threads on it, but i'd say a good portion of the forum finds it to be true and there are a few that find it as hocus pocus.

 

1. Exhaust: This is a tough answer. Depends on what you want. LOUD. Free flowing. Quiet but cool looking, etc. I think stock (~2.75 in) is good enough for making power. Theres really no power gain here. If I got an exhaust aesthetic purposes, it would be a quiet one.
2. Intake: K&N intake or ZZP intake. NOT HAHN.
3. Tuning software etc : HPtuners or Trifecta. I have HPtuners.
4. Suspension: stock is good, but if you want drop, someone else can answer. I hear a powell race bar is good.
5. This is a matter of opinion. I think the coolest wheels Ive seen are the stock Vauxhall wheels on a cobalt
6. I did treadstone, most will say ZZP. ZZP charge pipes for sure.
7. Forge BPV
8. TWM STS
9. Mishimoto Radiator.

 

As for the question in your first post, pretty much anything and everything from ZZP & Powell you can't go wrong with

 

DO NOT BUY HAHN!!!

Now that is out of the way. Buy your performance engine parts from zzp. Suspension mods for looks and keeping the stock feel, buy CM springs. Track suspension should come from Powell. Going koni yellow once the stocks go is a good idea to get or just for better suspension. Tuning should be done by hptuners. Stock brake pads are better than most aftermarket pads for the mix of daily/track brakes. Go for gmpp clutch when your stock one goes because of power increase or age. Also, get some aftermarket wheels, tire selection for stock wheels is horrible. Might be the next mod for next summer.

DAMN YOU MARYLAND REGISTRATION FEES!!!!!

 

How is the mishimoto? Someone told me it's a good cooling mod.

 

You don't need an aftermarket radiator on the stock turbo, waste of money.

 

I agree, I only have the ZZP radiator because since mine was broken I wasn't going to put in a factory one.

 

Which intake causes the least problems associated with the LTFT ...the K&N?
How do you tune out the LTFT problem?

THANKS!

 

Modified stock airbox with zzp intake tube doesn't require a tune and flows enough for any stock turbo car
Aftermarket kn
Needs to be tuned with hp tuners or thru trifecta

 

Its a pretty radiator but yeah, more than likely dont need it I cant tell you of the cooling performance because I havent even pushed it to the limits yet. havent been to the track in a while. Its the same dimension as the stock one but all aluminum. Not oversized. I only got it because it was free and I was the test fit car for it

i'd buy one if the stock one broke, definately a good replacement for stock.

 

Treadstone, Hahn, or K&N intakes all add about 10-15 whp on top of a tune. Stock turbo tuned on E-47 with full bolt ons maxes out at 360 whp on stock cams, stock motor.

 

Stock intake will give you the least problems associated with LTFT creep but if you want that SRI look, I think the K&N is the best bet. If you get LTFT creeping too positive or too negative, tuning is the only way to correct it. HPtuners is some good tuning software and there are plently of tuners around that can help you with that, even do logs, send the logs to the tuner, they write you a file and you load it up. Remote tuning.

If you get the K&N and you orient it the way most say to do it, you may see minimal changes in LTFT swings. If you can keep it within +6 and -6 LTFT, id say your okay with running the intake on the factory tune. If it hits double digits, you could try rotating the filter alittle in one direction or the other and see if the LTFTs change for better or worse.

Also you may have heard it already based on some of the previous comments but adding the intake on without any tuning will net you 0 hp gain. These cars are strange. You wont make power with adding bolt ons until the car is tuned.

I find the best thing to do is upgrade your downpipe, exhaust, charge piping (keep it on the bpv, not bov), upgrade you intercooler, and your intake (basically all the bolt ons) then tune the car. You should be able to do every single bolt on without effecting the cars performance on the stock tune as long as you either use the factory intake or a K&N and you dont get the LTFT creep. or you could do it the more costly way, throw on a downpipe then tune, throw on the charge piping then tune. Ive seen so many people inefficiently modify the car when they could have gotten away with doing one tune.

 

I will second the DONT BUY HAHN. Lol it rusts. Powell seperator first, works awesome, the. All pipes and intercooler to get ride of plastic crap that breaks, downpipe, tune, Powell rotated tranny mounts and hard core rear sway bar, zzp zfr turbo, intercepter gauges. Ect

 

Mine did not rust but then again I live in Florida.

 

I have a feeling the Hahn rust issue is specific to a certain batch of intakes made of incorrectly spec'd material, not all Hahn intakes. I'll see about doing some analysis of kevin's hahn intake when he replaces it and see what metal mix his high-nickel steel actually is.

 

Charge pipes don't need tuned for. Intercooler does really need tuned for either.

If I were you I'd get a down pipe, charge pipes, and intercooler all on then get the intake when you are reading to get tuned.

 

Okay this is interesting ...because the MAF senses air molecules moving past the sensor. So if the K&N was actually providing more air flow wouldn't the MAF and then ECU be sensing it and add more fuel in all cases? Since the ECU is not used to the air flow seems it would always add more fuel, so fuel trim creep should always be creeping toward rich.....but it appears it also creeps sometimes towards lean?....I wonder why?

Is our MAF a hot wire sensor ?

I did read that HP Tuners allows you to tune it out correctly if you follow the instructions. I plan on buying the HP tuners and the full instructions course that comes with it as my first mod...thanks everyone...!

 

So seems everyone basically agrees on these performance mods??: ZZP downpipe, ZZP charge piping, ZZP intercooler, K&N intake and HP Tuners.

What HP should I be running at this point with a conservative low 11's AFR ratio tune?

 

^320/380

 

Awesome...

By the way someone mentioned they were running 12.8s....is this normal for this engine to run this lean at WOT?
I have always been told low to mid 11's to stay away from knock and keep the engine longevity.


Any recommendations on STS?
Worth it?

 

STS...BPS is a popular choice.

 

I have a twm sts. Best mod so far.

 

I'd recommend a BPS over TWM.

 

You do not want low 11s on your AFR on a GDI motor.