NewOrleansLT1

So I finally ditched the mid tubes for the long tubes, but when I got the car tuned it had the mids. So my question is will the PCM compensate for that extra little airflow? I know he tuned it with a 13.00 afr so that's what had me wondering if the extra air flow will lean it out or??

Ed Wright

iTrader: (1)

The MAF will compensate some. May be enough. A speed density car would lean out. You may very well be fine.

NewOrleansLT1

Thanks Ed..

MMWS6

Most tuners will give you a wicked deal for a small adjustment like you need. I would be contacting your tuner and see what they would be willing to do. All you need is a little adjustment to your fueling tables and maybe an adjustment to your timing tables. Even just a quick WOT run with a WB, just to touch it up

NewOrleansLT1

I guess I'll have to pay for a touch up..

Ed Wright

iTrader: (1)

There is no reason to change the spark advance for longer header tubes. LOL
I have dyno tested several like this, some may lean slightly, many are fine. Odds it's OK are better than 50-50. The MAF "sees" the added air flow, and if everything is OK more often than not it's still OK.

MMWS6

You really don't think idle timing would need a little clean up going to long tubes? I would think that his timing is going to drop a little at idle to keep exhaust temps high enough to keep his O2's reacting properly, especially if the engine is cammed?

Ed Wright

iTrader: (1)

Not if it was done correctly the last time.

NewOrleansLT1

Ever since I installed the long tubes the car drove a little rough but when I get down on it it's smooth as butter. I thought the PCM had to learn its new environment but it didn't. So I unplugged the o2 sensors and the car drove PERFECT! Why is that? O2 sensors are new. Could it be that their not getting hot enough?

Ed Wright

iTrader: (1)

People do that every day with no issues. What do your fuel trim numbers look like?

NewOrleansLT1

I really don't have access to tuning software but I do know that when it was being tuned with the mid headers afr was about 13.00

Ed Wright

iTrader: (1)

That takes a scam tool, not tuning software.