[JoeLentoni]

So im deciding which headers to get for my 2007 e92 328xi manual coupe. The AFE twisted steel headers are a bit more costly compared to the AA headers which do you prefer. Which one is proven to increase more power

[tdavis42]

AA headers are on sale right now for 850 new. Just ordered mine.

[rjahl]

Originally Posted by JoeLentoni

So im deciding which headers to get for my 2007 e92 328xi manual coupe. The AFE twisted steel headers are a bit more costly compared to the AA headers which do you prefer. Which one is proven to increase more power

I think your question is a little open ended. If power is your only criteria are you planning on a new tune after the header install? Who's tune? Custom or off the shelf?

For the most gains you will need a new tune. I would ask your tuning shop this same question. They probably have worked with both types of headers and can give you their opinion based on actual dyno results. Of course AA might be a little biased.

I assume you are comparing catless versions of the AFE headers.

I'm looking at the same upgrade for my car but I have far fewer options with the E85.

[JoeLentoni]

Originally Posted by rjahl

I think your question is a little open ended. If power is your only criteria are you planning on a new tune after the header install? Who's tune? Custom or off the shelf?

For the most gains you will need a new tune. I would ask your tuning shop this same question. They probably have worked with both types of headers and can give you their opinion based on actual dyno results. Of course AA might be a little biased.

I assume you are comparing catless versions of the AFE headers.

I'm looking at the same upgrade for my car but I have far fewer options with the E85.

Im just looking for the best numbers i would have a tuning shop tune it

[hassmaschine]

I would go with BPC, unless you know a tuning shop that happens to have specific knowledge of the N52, which I am skeptical.

[tdavis42]

What about running AA headers with no tune? How will that affect the car?

[Taskmaster]

You can run any header with any (or no tune) you want.

Want the most power? AA/SS headers would PROBABLY net the most, paired with a tune from BPC.

Want to pass the sniffer? AFE headers say they will, and won't trip the light even without a tune. You can add on a BPC tune for good measure.

Don't want to tune at all? You don't have to, but you won't be getting the most out of your investment.

[tdavis42]

Originally Posted by TheAxiom

You can run any header with any (or no tune) you want.

Want the most power? AA/SS headers would PROBABLY net the most, paired with a tune from BPC.

Want to pass the sniffer? AFE headers say they will, and won't trip the light even without a tune. You can add on a BPC tune for good measure.

Don't want to tune at all? You don't have to, but you won't be getting the most out of your investment.

I'm going with the BPC tune but that is my final piece. AA headers should be here next week and I already have the 3IM and PE.

[mike@x-ph.com]

Originally Posted by tdavis42

AA headers are on sale right now for 850 new. Just ordered mine.

Congrats!!

Pictures?

[tdavis42]

Originally Posted by mike@x-ph.com

Congrats!!

Pictures?

None yet..... They arrive Tuesday along with the tune from BPC.

[Taskmaster]

Originally Posted by tdavis42

None yet..... They arrive Tuesday along with the tune from BPC.

BEFORE AND AFTER DYNO!

[Ruddigger]

Originally Posted by TheAxiom

BEFORE AND AFTER DYNO!

Yes. The before is particularly important.

[Taskmaster]

Originally Posted by Ruddigger

Yes. The before is particularly important.

As far as I know, he's automatic, it be invaluable for the majority of the guys out there.

[tdavis42]

Originally Posted by TheAxiom

BEFORE AND AFTER DYNO!

Was waiting for this..... BTW where is your before and after dyno??

[Taskmaster]

Originally Posted by tdavis42

Was waiting for this..... BTW where is your before and after dyno??

I have a before dyno (I have 6 different dynos that I've done), my after one is waiting for a cool day, non-humid day.

[tdavis42]

Originally Posted by TheAxiom

I have a before dyno (I have 6 different dynos that I've done), my after one is waiting for a cool day, no humid day.

It really was a serious question. I never saw any from you that's why I'm giving you shit. Not trying to be dick even though it might have come off that way.

[boro92]

A note about headers that have been discussed in other threads: the AA ones place the O2 sensors in a different location from stock. This affects how the DME will respond to the readings it sees from the O2 sensors, due to a variance in the timing of those signals.

The factory bmw DME for the Z4 3.0 and other cars N52 tubular headers from factory actually account for this in the tune. Doesn't seem like any off the shelf tunes account for this (except maybe BPC)

[STR8-6IX]

Originally Posted by tdavis42

What about running AA headers with no tune? How will that affect the car?

Tune is highly recommended. you wont get all possible gains without it. ECU will not know what to do with the upgrade.

[STR8-6IX]

Originally Posted by boro92

A note about headers that have been discussed in other threads: the AA ones place the O2 sensors in a different location from stock. This affects how the DME will respond to the readings it sees from the O2 sensors, due to a variance in the timing of those signals.

The factory bmw DME for the Z4 3.0 and other cars N52 tubular headers from factory actually account for this in the tune. Doesn't seem like any off the shelf tunes account for this (except maybe BPC)

AA claims you cannot tune headers "for the n52" or something. you cant tune THEIR headers to it, or at least not as well as you can due to the different placement of O2 sensors.

[Taskmaster]

Originally Posted by boro92

A note about headers that have been discussed in other threads: the AA ones place the O2 sensors in a different location from stock. This affects how the DME will respond to the readings it sees from the O2 sensors, due to a variance in the timing of those signals.

The factory bmw DME for the Z4 3.0 and other cars N52 tubular headers from factory actually account for this in the tune. Doesn't seem like any off the shelf tunes account for this (except maybe BPC)

I don't know that they do either, nor does anyone know exactly what type of delay they are measuring.

[boro92]

Originally Posted by TheAxiom

I don't know that they do either, nor does anyone know exactly what type of delay they are measuring.

Yes, I have no idea myself
I cheaped out and just did cat deletes on the stock manifolds (going in for this - next week). Didn't want to mess with that.

[mmmnot]

Originally Posted by TheAxiom

You can run any header with any (or no tune) you want.

Want the most power? AA/SS headers would PROBABLY net the most, paired with a tune from BPC.

Want to pass the sniffer? AFE headers say they will, and won't trip the light even without a tune. You can add on a BPC tune for good measure.

Don't want to tune at all? You don't have to, but you won't be getting the most out of your investment.

I have AFE - it triggered CEL. Needed AA to code it out.

I have personal beef with AA and their support - I would rather run OEM cats than AA if AFE was not in question.