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#4
Ceramic headers lose less heat from the exhaust gasses. That's helpful if you're feeding a turbo, or to help the cat light off quicker. Less under-hood heat means the intake air stays cooler.
#5
Le Grand Illusion
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The way I've always read it is:
4-2-1 makes good low and mid-range hp and torque... some small gains up top.
4-1 *reduces* low and mid-rpm power/torque, but makes huge gains up top. It's a trade-off... if it's daily driven, I would recommend 4-2-1.
4-2-1 makes good low and mid-range hp and torque... some small gains up top.
4-1 *reduces* low and mid-rpm power/torque, but makes huge gains up top. It's a trade-off... if it's daily driven, I would recommend 4-2-1.
#6
Originally posted by spooncivicb16b
there is no performance difference between stainless and ceramic coated headers right?
there is no performance difference between stainless and ceramic coated headers right?
In addition, high temperatures are good for exhaust gas velocity, which is one of the reasons people are so fond of header wraps, sprays, etc.
BUT most ceramic coated headers are mild steel, which can be prone to cracking, rusting, and other annoyances.
So let me break it down:
Ceramic coating :thumbup:
Mild steel :thumbdown
Stainless steel :thumbup:
Ceramic coated stainless steel :thumbup: :thumbup:
Originally posted by DelSolSIinMD
4-2-1 makes good low and mid-range hp and torque... some small gains up top.
4-1 *reduces* low and mid-rpm power/torque, but makes huge gains up top. It's a trade-off... if it's daily driven, I would recommend 4-2-1.
4-2-1 makes good low and mid-range hp and torque... some small gains up top.
4-1 *reduces* low and mid-rpm power/torque, but makes huge gains up top. It's a trade-off... if it's daily driven, I would recommend 4-2-1.
Second, where the greatest power gains given by a header are located in the power band depends more on when and how the primaries merge than the basic layout.
For example, on many more expensive headers (such as the Spoon header shown below), you may see a 4-2-1 design, but the two merges are done in close succession just before the catalytic converter, in the style of a 4-1.
This tri-Y design creates a middle ground between 4-1 and 4-2-1 headers, and with modification of the distances between the merges you can create almost any desired result.
What you were saying was basically correct, but it is a lot more complicated than you may have thought.
#8
Le Grand Illusion
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Originally posted by qtiger
Well... yes and no. Ceramic coated headers are more heat resistant, and therefore should keep your underhood temps lower.
In addition, high temperatures are good for exhaust gas velocity, which is one of the reasons people are so fond of header wraps, sprays, etc.
BUT most ceramic coated headers are mild steel, which can be prone to cracking, rusting, and other annoyances.
So let me break it down:
Ceramic coating :thumbup:
Mild steel :thumbdown
Stainless steel :thumbup:
Ceramic coated stainless steel :thumbup: :thumbup:
First of all, a street designed 4-1 header should never lose low end power over stock. They may not provide gains anywhere near the magnitude of a 4-2-1 setup on the low end and midrange, but in general the OEM units flow pretty miserably (with the exception of R models) and to lose power an aftermarket header would either have to be A) too large for your setup or B) poorly designed.
Second, where the greatest power gains given by a header are located in the power band depends more on when and how the primaries merge than the basic layout.
For example, on many more expensive headers (such as the Spoon header shown below), you may see a 4-2-1 design, but the two merges are done in close succession just before the catalytic converter, in the style of a 4-1.
This tri-Y design creates a middle ground between 4-1 and 4-2-1 headers, and with modification of the distances between the merges you can create almost any desired result.
What you were saying was basically correct, but it is a lot more complicated than you may have thought.
Well... yes and no. Ceramic coated headers are more heat resistant, and therefore should keep your underhood temps lower.
In addition, high temperatures are good for exhaust gas velocity, which is one of the reasons people are so fond of header wraps, sprays, etc.
BUT most ceramic coated headers are mild steel, which can be prone to cracking, rusting, and other annoyances.
So let me break it down:
Ceramic coating :thumbup:
Mild steel :thumbdown
Stainless steel :thumbup:
Ceramic coated stainless steel :thumbup: :thumbup:
First of all, a street designed 4-1 header should never lose low end power over stock. They may not provide gains anywhere near the magnitude of a 4-2-1 setup on the low end and midrange, but in general the OEM units flow pretty miserably (with the exception of R models) and to lose power an aftermarket header would either have to be A) too large for your setup or B) poorly designed.
Second, where the greatest power gains given by a header are located in the power band depends more on when and how the primaries merge than the basic layout.
For example, on many more expensive headers (such as the Spoon header shown below), you may see a 4-2-1 design, but the two merges are done in close succession just before the catalytic converter, in the style of a 4-1.
This tri-Y design creates a middle ground between 4-1 and 4-2-1 headers, and with modification of the distances between the merges you can create almost any desired result.
What you were saying was basically correct, but it is a lot more complicated than you may have thought.
#9
Originally posted by Slow-N-Low
Ceramic headers lose less heat from the exhaust gasses. That's helpful if you're feeding a turbo, or to help the cat light off quicker. Less under-hood heat means the intake air stays cooler.
Ceramic headers lose less heat from the exhaust gasses. That's helpful if you're feeding a turbo, or to help the cat light off quicker. Less under-hood heat means the intake air stays cooler.
#10
Originally posted by spooncivicb16b
so which will make the vtec crossover more dramatic or smooth
so which will make the vtec crossover more dramatic or smooth
Originally posted by DelSolSIinMD
It *is* more complicated! ... that's interesting, and thanks for the info. I'm looking for headers now, actually, and this gives me more meat to chew on. Sweet! :thumbup:
It *is* more complicated! ... that's interesting, and thanks for the info. I'm looking for headers now, actually, and this gives me more meat to chew on. Sweet! :thumbup: