Headers Advice

[cgundermann]

I have a MK4 with a fuel injected 347. It is a basic kit with the J-pipes for unequal length shorty headers. I have spoken to FFR twice and gotten two separate opinions: one is that Mustang long tube BBK headers without using J-Pipes (and have the O2 bungs) will work, and the other tech stated that only unequal length shorty headers with their J-pipes will work (according to him - equal length shorty headers and J-pipes will not work).

I am using a Pro-M racing computer and wide band O2 sensors and would prefer to have the bungs welded in before ceramic coating. My motor according to The Engine Factory is around 450 horse. I know FFR sells a BBK header - but no O2 bungs.

I know Stainless Headers will build a set, but it is spendy or I can go BBK unequal length shortys and J-Pipes. In terms of power, sound and fitment - what are the experts recommendations? If I go Stainless Headers, because of the price - I would be less inclined to spend the $150 for the jig to ensure side pipe alignment.

Appreciate everyone's input,

Chris

[MPTech]

standard 302 block, correct?
I ran the FFR / BBK Ceramic headers and drilled the holes and had the O2 bungs welded in. Runs great and I like the look better than the J-pipes.

[GWL]

I have a Ford Small Block, 302. I've fitted unequal length Ford Racing Shorty Headers onto GT-40p heads and the fit is fine except the passenger side lower header hits the engine mount a bit. I've raised the engine with two washers and the fit is good. Not running yet and the engine will twist toward that passenger mount when hitting the gas, so I'll wait to see how it works later.

It is best to locate the O2 sensor in the J pipe so it can read all the cylinders on that bank. That is why you wouldn't usually see them on full length headers.

George

[Dan Babb]

Stainless headers will build a set that has a merge in the header for your 02 sensor...but even more spendy.
They show them on their coyote page: http://www.stainlessheaders.com/coyote
I think another member had them build headers for a 302 like this.


I have the FFR 4-into-4 headers on my 347 EFI and just have one tube on each side bunged for the 02 sensor. Not ideal but the car runs great. Other guys have put the 02 sensors down in the side pipe collector (but with the mass-flo EFI setup I have, they state to have the 02 sensor a certain distance from the head and going out to the collector is too far.

[cgundermann]

I appreciate everyone's advice; is it true that the J-Pipes only work with unequal length headers and not with equal length in terms of fitment to the side pipes? Also - shouldn't my wide band O2 sensors be pulling from a collector point and not one exhaust tube? MPTech - are you using the standard Ford ECU and oxygen sensors? I spoke to Stainless Headers and they can weld in a bung for me, but it is not at a collector point...I can also weld one into the FFR/BBK pipes. The Pro-M Racing ECM and wide band oxygen sensors are real precise, that being said - maybe I should go with a J-Pipe for precise metering?

[GWL]

I think you have two questions here.

Do unequal length fit up to the J pipes? I don't know but am thinking they would exit at the same point as the shorty headers. I chose the shorty headers to be able to enlarge the footboxes the most I could.

If you want precise metering, put the bung/sensor in the J pipe. I too have read that putting the sensor too far away from the heads is not recommended. With that said, I'm going to have to lengthen my Ford Racing engine wiring harness to reach the sensors on the J pipe. Working on that now.

George

[rich grsc]

I appreciate everyone's advice; is it true that the J-Pipes only work with unequal length headers and not with equal length in terms of fitment to the side pipes? Also - shouldn't my wide band O2 sensors be pulling from a collector point and not one exhaust tube? MPTech - are you using the standard Ford ECU and oxygen sensors? I spoke to Stainless Headers and they can weld in a bung for me, but it is not at a collector point...I can also weld one into the FFR/BBK pipes. The Pro-M Racing ECM and wide band oxygen sensors are real precise, that being said - maybe I should go with a J-Pipe for precise metering?

BBK equal length headers fit the J-pipe just the same as the unequal length ones, I have them. That being said, changing plugs on the drivers side is a bit of a challenge, but doable. Shorties and J-pipes may be a little quieter (?) than the along tube headers.

[cgundermann]

Thanks everyone - I have O2 gauges to display the values of the wide band sensors (so I want precise metering) - although Stainless Headers can create a beautiful set with a collector/bung - it is a $1000 dollars. I am going to go with BBK unequal length and have my J-Pipes ceramic coated. Appreciate everyone's time!