Full length header test

[Katastrophe]

I'd still be interested in seeing the differences between 1 7/8" and 2"...especially at high RPM.

I know it isn't apples to apples, but a lot of built high revving Honda engines (I'll use that as an example, because I'm familiar with them - specifically the K20) love to have larger headers and exhausts...especially when 8-9K redlines are the norm.

Edit: Whoops. Meant to reply to someone with this comment, but didn't, Haha! Whatever, I'll keep my thoughts and speculation out until we see some numbers.

Sponsored

 

[DWC_SmOziLLa]

I was under the impression that the bolt pattern and mounting flange for the exhaust manifolds is slightly different on the 5.2 versus the 5.0 and that the headers are not interchangeable :shrug:

 

[Voodooo]

I was under the impression that the bolt pattern and mounting flange for the exhaust manifolds is slightly different on the 5.2 versus the 5.0 and that the headers are not interchangeable :shrug:

Correct

 

[Voodooo]

Why do people think bigger is better?

 

[Voodooo]

There's two trains of thought here:

First one would be, "I am buying a header/part and I will tune around the header."

Second one would be, "I have baselined and I understand what my performance goals are and therefore I can build a header/part around my goals, not my goals around the header (or whatever performance part for that matter)."

The second sounds like a more focused strategy. But you're First to Market and it's your money so go for whatever you think is right. I'm just trying to offer suggestions or insight particularly since this is such a new platform. We have NO clue how it's going to respond.

What I am saying is this.
Baseline Dyno pulls
Jlt Dyno pull
Tune Dyno pull
Header Dyno pull
Tune Dyno pull

Nobody is building anything around headers. The engine is already built. We're testing and tuning around a stock engine. Have you ever built a engine from scratch?
You don't build a bottom end with say for example high compression that you plan on running naturally aspirated and port the heads for naturally aspirated along with cams. Then put a blower on it. That's foolish. We're not talking about that here.
I've built many race engines and I love naturally aspirated high compression engines, I've also built forced induction engines and they all require different set ups if you want to reach your goals. Anyone can put a supercharger on a engine and make power. But to tune for it and to get the most from it is another thing. This is my point about header size.

 

[nastang87xx]

Why do people think bigger is better?

Because of marketing.

Baseline Dyno pulls
Jlt Dyno pull
Tune Dyno pull
Header Dyno pull
Tune Dyno pull

That's what I'm talking about. Then you can choose your header based on what happens after that tune pull with the JLT.

Have you ever built a engine from scratch?

Yep.

You don't build a bottom end with say for example high compression that you plan on running naturally aspirated and port the heads for naturally aspirated along with cams. Then put a blower on it. That's foolish. We're not talking about that here.

You're starting to kinda chase your tail here. We know.

It originally sounded like you were going to just pick a header off of preemptive assumptions from engines of past. So we're back on the same page here.

 

[mustang_guy]

Because of marketing.



That's what I'm talking about. Then you can choose your header based on what happens after that tune pull with the JLT.




Yep.



You're starting to kinda chase your tail here. We know.

It originally sounded like you were going to just pick a header off of preemptive assumptions from engines of past. So we're back on the same page here.

Im going off what ive seen for the 5.0s. Not marketing.

 

[Voodooo]

Because of marketing.



That's what I'm talking about. Then you can choose your header based on what happens after that tune pull with the JLT.




Yep.



You're starting to kinda chase your tail here. We know.

It originally sounded like you were going to just pick a header off of preemptive assumptions from engines of past. So we're back on the same page here.

As I said before. I don't think you understand the reasoning of the Tri Y or step headers. It doesn't matter if it's a antique engine or modern engine. If it proves to work then use it.

 

[Grimace427]

Im going off what ive seen for the 5.0s. Not marketing.

Same here, though I tried to find some references but couldn't find them at the time so I didn't post. Every dyno test I've seen comparing 1 3/4" to 1 7/8" showed greater gains with the larger primaries. The differences were small, but there were zero losses anywhere in the powerband with the larger primaries.

 

[BmacIL]

How do you know what to find if you don't know what you're looking for in the first place? Baseline it. Tune it. Analyze the tune. Add a focused purpose build header based on the findings of the tune. I'm not saying don't get headers, just figure out what you're working with BEFORE you choose a header design. I'm sure ARH will do pretty much whatever you want too since you'll be FTM.

There's a great program called GT Power that allows you to model your engine and design your air path based on it. It's surprisingly accurate and surprisingly effective. I agree that you should baseline tune, understand what the current limitations are for breathing, and design your headers around those known limitations. Sure, a nicely manufactured, equal length setup will net some gains. How would you know if it's the right header setup until you've understood where changes are needed? This is called engineering.

 

[nastang87xx]

I'd still be interested in seeing the differences between 1 7/8" and 2"...especially at high RPM.

I know it isn't apples to apples, but a lot of built high revving Honda engines (I'll use that as an example, because I'm familiar with them - specifically the K20) love to have larger headers and exhausts...especially when 8-9K redlines are the norm.

It's not the redline so much as the volume of exhaust gases that are being pushed through the VTec motors when they're spinning that fast. It's not that they don't received a performance benefit with a 1 3/4 or even a 1 1/2 so much as the tradeoff for the increased lower grunt (which isn't much) isn't worth it so it's just better to use a 1 7/8".

 

[nastang87xx]

As I said before. I don't think you understand the reasoning of the Tri Y or step headers.

Actually I do understand the designs but let's not start another argument. We clearly have different ideologies on the process and I'm 100% okay with leaving it at that.

 

[nastang87xx]

Im going off what ive seen for the 5.0s. Not marketing.

]Same here, though I tried to find some references but couldn't find them at the time so I didn't post. Every dyno test I've seen comparing 1 3/4" to 1 7/8" showed greater gains with the larger primaries. The differences were small, but there were zero losses anywhere in the powerband with the larger primaries.

Do you guys have any articles of those comparos? I'd be very interested.

 

[Voodooo]

Some People kill me.

 

[nastang87xx]

Some People kill me.

I could say the same about you wanting to go mad balls on your brake cooling and yet you haven't even found the limits of them yet. But that's none of my business.

Sponsored