Frank Talk About Headers Requested

Slams beer... Glad we could clear things up. Not trying to blast anyone, just wanted to keep any misinformation from spreading and confusing things.

Another option is the Lethal O/R pipes. They're about $450, have flex sections, and retain the dampers. Seems like a decent deal for 10-15 whp without tuning, but the volume would be outrageous. However, they would retain the "Mustang chasing a Ferrari" character of the exhaust pulses provided by the funky stock headers, even amplifying it.

OP Says "Thanks!"

When I started this thread I had a lot of questions. As I said earlier, I put headers on many cars, but this was the first toy I had severe misgivings about adding headers to.

With over 2000 views and dozens of responses it seems like very few people have put headers on their cars. And it seems there are good reasons for this. A lot of money to buy, ceramic coat, and install headers on our cars, for about 20 h/p. Worth it? Most seem to think "no."

I have lately been running elevated octane (around 97) for now, and there definitely seems to be a few extra ponies over 93. And I am mixing 100 octane race fuel right now - could run 100 percent of this (at $10 a gallon) for probably a solid 15 or so h/p on top of my mods. Maybe about 485-490 rear wheel - which equates to maybe 575 flywheel. So, though a bit pricey, I could buy a lot of this juice for $3k!

Not running the corn because it is so hydroscopic and living in Fla, do not drive the car more than once a week or so.

Bottom line for me? No headers for at least the near future. Looking more to lightening and handling improvements now.

Thanks to everyone who contributed to this thread! :cheers:

nastang87xx said:

........GM has run narrowbands for so long it's not even funny. I think the C7 and the Alpha Camaro are STILL running on narrowbands. :doh:

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Really? Even my 2004 Subaru WRX uses a wideband and adjusts fueling based on comparisons between MAF and O2 sensor readings. That is the first thing I review (calculated fuel trims) to see if I have a small vacuum or boost leak.

I can't believe that any auto manufacturer exclusively uses narrow band O2 sensors for fueling. I figured narrow bands were only used for catalytic converter efficiency these days.

First off, The ford calibration has a virtual VE system that calculates how much air is filling the cylinder as well as flowing through the system due to valve position / overlap and not a result of "lean" combustion. This is documented at HP Tuners. Yes the car has a MAF sensor, yes you can probably drive the car fine as the air coming into the system will be measured. But this also moves the MAF curve slightly due to the improved VE. MAF sensors and the transfer functions are not straight lines. This is a fact.

So you are taking in more air, your VE model is changed slightly, and the internal calibration corrections for cylinder fill are off slightly. Will your engine blow, no not likely. Is it "optimal", no.

If I am going to add long tubes and especially if I'm deleting cats I am also going to confirm my MAF curve. I'm going to be sure my fuel tables are spot on. I am also going to be sure I load up the engine and get everything right on a dyno.

My car hated the lethal off road pipes with a canned tune. I will sell them to anyone local in Ohio cheap. Another member here needed to have Lund add fuel to his tune when he added ARH headers without cats. His car was going lean enough Watson shut it down on the dyno. your mileage may vary

I always thought at WOT, the engine was ignoring O2 readings and strictly reading from parameters loaded into the ecu..

I have been told both, unfortunately by people I would otherwise trust. One said that once it went into PE mode and the torque model locked into the OP mapped point it would use those tables and only take positive trims into that area.

Another tuner equally versed told me the O2s were always active to an extent. He didn't clarify how much if at all it effected PE or OP mode.

I really cant say yet. I am going to try and tune mine with a friends help but it is going to be on a ford performance OS.

AirBusPilot said:

I always thought at WOT, the engine was ignoring O2 readings and strictly reading from parameters loaded into the ecu..

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Correct, Open loop

[MENTION=20919]superman07[/MENTION] are you going to a long tube with the whipple?

If I understand what you’re saying, i should datalog with lund after getting the shifteck midpipe?

Screamer said:

Correct, Open loop

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Does the ECU not apply learned fuel trims across selected airflow ranges? I have very little knowledge of Ford fueling strategies.

Other ECUs I've tuned have four or five fuel/air trims that are applied in open loop.

For example (not literal values):

A/F Trim 1: applies to air flow ranges of 0-10 g/s
A/F Trim 2: applies to air flow ranges of 10 - 50 g/s
A/F Trim 3: applies to air flow ranges of 50 - 100 g/s
A/F Trim 4: applies to air flow ranges of 100 - 200 g/s
A/F Trim 5: applies to air flow ranges greater than 200 g/s

When the ECU determines that parameters are met that forces open loop fueling, the fueling lookup tables were modified by the learned deficient (lean) or excess (rich) fueling in each of those airflow ranges. When the MAF spit out 117 g/s, the ECU would modify the programmed fuel amount using the A/F trim 4.

If the ECU follows this kind of fueling strategy, I would expect it could account for small differences in VE. But, I honestly have no idea how much VE change there is when adding headers, so not sure if it could properly account for them or not.

Fords ECU is torque based, as you request torque you go into through mapped points or infer across multiple until you "snap to" a particular point. I would expect the trims to use the same core logic and not be a pure function of air flow, but I defer to someone that may know exactly.

Always log, its just a good thing to do periodically anyway. Mid-pipe is going to be fine regardless.

Yes, I think I am going to go cat-less so I can also remove COT logic to a degree.

jvandy50 said:

@superman07 are you going to a long tube with the whipple?

If I understand what you’re saying, i should datalog with lund after getting the shifteck midpipe?

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Hey guys.

I know this is an older thread but I’ve just finally made a forum account and plan to be active with it and start a build thread on my 350. Recently bought a 18 after having built a 900WHP 3.6L kenne bell 2015 GT. Am more active on IG previously as rubyredrocket and now as shadowblackbeasts as I also have a 2018 coyote F150 with a whipple.

I had kooks on my GT but decided to give ARH a try this time around

My experience with ARH on the 350 hasn’t been a pleasant one and will likely go back to kooks at some point.

#1 reason is that ARH didn’t take the time to make a specific header for the 5.2, it’s the exact same header for the 5.0 with the 5.0 bolt pattern so you have to move the studs around and use GT gaskets. That’s not acceptable to me on a 60k car for them to not take the time to do it right which kooks did.

Since it’s a 5.0 header it has no provision for the dampers or a flex portion to help with some of the vibration so you better have your tips lined up perfectly in the rear valance or get ready for rattle city.

#2 reason is because they aren’t a thought out header for the 5.2 on the driver side runner #2 is dangerously close to the valve cover and I have no doubt over time will melt that area.

#3 lastly and this is probably not a issue for most but when my headers went on we hit the dyno on a E85 tune from Lund and then had to spend a week chasing down false knock that we couldn’t figure out. Finally found out it was the passenger header. 2 of the runners were barely touching each other and rattling because of the extreme vibration of the voodoo.

ARH did send out a replacement at no cost but did not cover the 400$ I had to pay to swap them.

Overall not happy with the whole thing and plan to go kooks at some point with jet hot coating.
I know ARH is well known for quality and making decent gains but they should have taken the time to design a 5.2 header that took into account the different firing order of our motor and the vibration issues and quality checks and not just send out 5.0 headers and tell the customer make it work. That’s my 2 cents.

Lastly I tried many different set ups with headers to get the right sound and here is my findings

1-LTH with no cats and a Corsa x pipe and stock mufflers the car was loud as hell and raspy,very raspy and metallic sounding in a bad way, but it lost all of that FPC voodoo sound that is one of the best parts of this car. And with the valves closed the valves would rattle and make a terrible sound. If you like nascar loud that was the set up for you.

2- LTH with high flow cats, Corsa x pipe and stock mufflers the metallic sound was mostly gone and the valves didn’t rattle when closed but it still had a lot of rasp and at WOT sounded like every other V8 mustang. No distinct voodoo sound

3- and this is what I settled with - LTH with high flow cats and stock exhaust including resonators (picked up a brand new set) this is the winner to me. Rasp is gone/voodoo FPC tone is back even at WOT just much louder which is what I was hoping for. Keep the beautiful tone of the FPC with that exotic song just much more volume and that’s what I got. Once I figure this whole forum thing out I’ll start trying to get sound clips etc lol. Just bare with me

did any one else catch the flame at 1:31 when he shifted