TK-421
New member
Whoa whoa whoa wait who the hell is saying equal length headers prevents ringland failure? That is a load of shit
Best "bang for the buck" modifications for WRX's and STi's
- Thread starter Alin
- Start date
Whoa whoa whoa wait who the hell is saying equal length headers prevents ringland failure? That is a load of shit
TK-421
New member
Don't see how he is saying that equal length headers themselves prevent ringland failure. Granted some of those listed in conjunction with each other will help prevent ringland failure, does it mean that it will stop it completely absolutely not.
TK-421
New member
That's a load of crap. Header design does not create failure in the Pistons. There are plenty of customers of mine out there that still run the stock manifold with no issues. [MENTION=1172]Alin[/MENTION] being one of them.
TK-421
New member
Subaru has been using this design of header for decades now. It isn't the design of the header that causes these issues. It's a cause of poor quality of materials. And cost cutting in the quality of parts in fueling. Many people such as yourself have switched out the FPR on GR/GV vehicles.
Around 70% of fuel is used for thermal heat dissipation, if fueling is cut by a poor design into a certain cylinder, most people will point the finger at heat in the exhaust collector. Doesn't matter if the header is changed or not, if the heat cannot be controlled the piston will still ultimately fail.
That's the Theory.
Cylinder #4 has longer exhaust manifold runners which leads to higher EGTs
#4 receives fuel later in the path (fuel gets to other cylinders first so the pressure has dropped by the time it gets to #4)
The intake manifold flows more air to #4 so it runs consistently leaner
The factory ECU runs more timing on #4 than the others so it will be the first to knock and trigger the ECU to pull timing (the ECU can hear knock better on #4 than the others because that's where the knock sensor is)
Cylinder #4 has longer exhaust manifold runners which leads to higher EGTs
#4 receives fuel later in the path (fuel gets to other cylinders first so the pressure has dropped by the time it gets to #4)
The intake manifold flows more air to #4 so it runs consistently leaner
The factory ECU runs more timing on #4 than the others so it will be the first to knock and trigger the ECU to pull timing (the ECU can hear knock better on #4 than the others because that's where the knock sensor is)
TK-421
New member
That theory is a NASIOC theory and most of those theories are complete crap.
TK-421
New member
Viking really? Come on man, your gonna believe the garbage that place puts up?
9 out of 10 TUNERS that you talk to will completely echo what I'm saying. It doesn't matter what exhaust manifold you have on the car, the primary thing will be the tune, and fueling.
Trying to justify your research and theory with me isn't going to change things. I build EJ series blocks for a living, I tune cars for a living, I do this everyday.
I am privy to what is called pattern failures.
The stuff that is put on other forums about headers is from people who generally chase horsepower and push their tunes to the edge. Unlike most reasonable people who like to keep things on the conservative edge.
The write up from Viking, please that's a performance shop, they are going to say anything they can to sell you a product.
[MENTION=4577]TK-421[/MENTION] as I said you are the expert here, I cannot argue with the technical stuff but I am trying to share what I have read about the theory, I cannot confirm or not to confirm because I bought the headers. I am just trying to save the pistons to run as long as possible.
I Like the sound of the Headers and the torque produced.
I Like the sound of the Headers and the torque produced.
TK-421
New member
If you honestly want to save the Pistons, look into air pump deletes, run the appropriate weighted oil, don't run Rotella or a thicker weight oil. And do NOT low load/high boost the vehicle. Always gradually increase boost when under 3500 Rpms. The majority of piston failure I have seen from most datalogs is from people that are physically hard on the car when it has some mechanical or tuning issue. And with the people saying they are blowing ringlands on a relatively stock car, it's usually due to them flogging on the car at low RPMS in high load areas in the sport sharp setting.
I have found over the years that more than 60% of the failure rate honestly boils down to driver error.
TK-421
New member
Lower EGT's still will not prevent ringland failure. The whole purpose im trying to get across here is that going equal length header WILL NOT prevent ringland failure. Will it decrease EGT in a certain cylinder and rpm range? Yes, by a lot? No. Will equal over unequal matter? Absolutely not. It's a preference. And generally most people go equal to squeeze as much as they can before having to step things up with a built short block and bigger turbo and supporting fueling mods
Nice info! So no more overtaking on 5th or 6th gear. Interesting tell me more about the air pump delete.
TK-421
New member
If your going to go into boost in low load areas say around 2800 Rpms and your in sport sharp and peak 19 psi right out of the gate, it can create a situation where the stock cast ringlands get stress cracks in them.
I always advise to downshift or stay in sport mode, If under 3500 Rpms I always give a rule of thumb not to exceed 8 to 10 psi after 3500 let her eat.
The air pump is a secondary air injection system that is there for emissions purposes. It will literally pump fresh air into the cylinder heads during the exhaust stroke to help with CO emissions. Does it really work? Maybe. Does it hinder performance and help with creating lean conditions? Damn right it does. You can delete the system with a pair of block off plates and erasing the codes with AccessTUNER or ECUFlash. It's relatively simple, just labor intensive since the air pumps and plumbing work it's a PITA to remove.
Older GD chassis cars like 04 to 06 do not have air pumps, but some 06 years started getting them early
TK-421
New member
Your welcome sir, come the start of April, there will be more articles that I will be writing up, once [MENTION=1172]Alin[/MENTION] brings his car to my garage and we start doing all of his mods, everything from fueling to turbo, to exhaust headers and Upipe to brakes and suspension. With the winter months it's hard to cover certain topics, especially with me being at my winter location and everyone else stuck in the snow
Similar threads
