Nameless Performance Equal Length Stepped Header

[feldy]

I got to tell ya. I was in my frs on the way up to a autocross two hours from here. Bill had the whole nameless protype header and full exhaust done. While it felt good on the autocross course. man it was loud to much for a daily driver. That's all we were talking about on the highway on how loud it is. Bill if you are on here have you been to the dyno yet? The butt dyno did feel great.

[Hawaiian]

Originally Posted by feldy

I got to tell ya. I was in my frs on the way up to a autocross two hours from here. Bill had the whole nameless protype header and full exhaust done. While it felt good on the autocross course. man it was loud to much for a daily driver. That's all we were talking about on the highway on how loud it is. Bill if you are on here have you been to the dyno yet? The butt dyno did feel great.

You drove mine, how was it compared to my exhaust noise wise?

[wparsons]

Anyone claiming that all the gains are from cat removal clearly knows nothing about fluid dynamics. There is A LOT more to a good header than just hacking off the header.

I don't know enough to design my own header, but I know enough to know that a properly designed/built header will make a bunch more power than something that's just slapped together.

[tennisfreak]

Originally Posted by wparsons

Anyone claiming that all the gains are from cat removal clearly knows nothing about fluid dynamics. There is A LOT more to a good header than just hacking off the header.

I don't know enough to design my own header, but I know enough to know that a properly designed/built header will make a bunch more power than something that's just slapped together.

So you're saying Jason @ Nameless doesnt know what hes talking about?

He told me himself that the majority of the gains come from a catless header and that is what I should get.

I'm not saying a pipe design could not be made to seriously f up the flow (because it could) but the stock headers and many other aftermarket headers are fine designs in themselves and there is no magical redesign of just the pipes that is going to get you a bunch of hp. The majority of the additional HP is from removing the catalytic converter.

[wootwoot]

If only they would log on and help solve some of this worthless banter...

[Calum]

Originally Posted by tennisfreak

So you're saying Jason @ Nameless doesnt know what hes talking about?

He told me himself that the majority of the gains come from a catless header and that is what I should get.

I'm not saying a pipe design could not be made to seriously f up the flow (because it could) but the stock headers and many other aftermarket headers are fine designs in themselves and there is no magical redesign of just the pipes that is going to get you a bunch of hp. The majority of the additional HP is from removing the catalytic converter.

But was the gain in power from removing the cat due to the cat not flowing well, or because it allowed them extend the primaries and/or secondaries farther down stream?

considering what they've gone through to fit this head in the engine bay (they were considering replacing the fans and water bottle if I'm not mistaken) I'd place my bets on the extra room being where they got the gains from.

[autobrz]

I read Jason on the forum say himself that having a proper length tubing was why the catless is better.

[pheoxs]

High flow cats don't impact performance nearly as much as some people expect. The mentality comes from years ago when they had to add cats for emisions and kill performance. Nowadays thats not nearly the same case.

The reason catless (in this case) is so much better is it allows you to route the pipes where you want. If you want a catted header then you need a decent amount of space before the flange to have the cat, and as a result need shorter runners before the merge.

Looking at something like the FA20 and P&L headers, they have the same runner length and just a different end piece for catted vs uncatted and the performance is near identical.

Its not the cat that hurts the performance, its the routing you have to use to physically fit the cat in there that does.

[chanomatik]

Listening to Scooby South's video of how the NP header sounds... I think I may hold off for a while. For daily driving it's overkill.

[Calum]

Originally Posted by Marchy

I love all the people talking like they know what's going on over at the nameless building. I'm not going to say i know what's going on, I don't, but I do know from talking to Matt that they are very busy and guess what, when you are very busy working multiple projects, stuff takes time.

If you don't want to wait for the nameless header, don't, there are options for you. If you want to wait, then do so. Bitching on here, or saying how nameless is miss managing their time is just stupid, and you look stupid doing so insinuating you have any insight on how they handle their time/business.

move on, or wait, those should be your two options.

The message above your avatar says you're a Canadian, but your info says you're in the US. Please, travel to where the beer isn't the same as having sex in a canoe. I think you need it.

[Dimman]

Originally Posted by Calum

But was the gain in power from removing the cat due to the cat not flowing well, or because it allowed them extend the primaries and/or secondaries farther down stream?

considering what they've gone through to fit this head in the engine bay (they were considering replacing the fans and water bottle if I'm not mistaken) I'd place my bets on the extra room being where they got the gains from.

It's about pressure in the exhaust system. Pressure comes from restrictions to flow (cats, small pipes, lots of bends), but also sound pressure which has a reversible wave.

The black magic of headers involves reducing flow based pressure while trying to maintain velocity (which is why bigger doesn't always mean better), and timing the sound-related pressure to optimize scavenging at certain rpm ranges. And the two ways of controlling that are with cam timing/overlap and the time a supersonic wave takes to reach the engine. Since the wave speed is pretty well fixed (egt can change local speed of sound) we can only control how far it goes. There is a slight trade off where reducing flow based pressure (big pipes) also reduces beneficial reversed sign sound based pressure. This is where the 'backpressure for torque myth' comes from. Another pain in the ass is the sound pressure tuning transfers to the intake side and things get even more confusing with cylinder to cylinder interaction of both exhaust and intake runners. The very PITA nature of the acoustics is why most people just focus on flow.

Hopefully they have been making good progress, and haven't ended up chasing their tails by focusing on flow vs acoustics or vice versa.

I wonder if anyone is ever going to figure out termination boxes. Quiet AND powerful NA? Never!

[Calum]

Originally Posted by Dimman

It's about pressure in the exhaust system. Pressure comes from restrictions to flow (cats, small pipes, lots of bends), but also sound pressure which has a reversible wave.

The black magic of headers involves reducing flow based pressure while trying to maintain velocity (which is why bigger doesn't always mean better), and timing the sound-related pressure to optimize scavenging at certain rpm ranges. And the two ways of controlling that are with cam timing/overlap and the time a supersonic wave takes to reach the engine. Since the wave speed is pretty well fixed (egt can change local speed of sound) we can only control how far it goes. There is a slight trade off where reducing flow based pressure (big pipes) also reduces beneficial reversed sign sound based pressure. This is where the 'backpressure for torque myth' comes from. Another pain in the ass is the sound pressure tuning transfers to the intake side and things get even more confusing with cylinder to cylinder interaction of both exhaust and intake runners. The very PITA nature of the acoustics is why most people just focus on flow.

Hopefully they have been making good progress, and haven't ended up chasing their tails by focusing on flow vs acoustics or vice versa.

I wonder if anyone is ever going to figure out termination boxes. Quiet AND powerful NA? Never!

What I said was meant to be a rhetorical question to point out the possibility that it was incorrect to make the assumption that the removal of the cat allowed for big gains because of the restriction to flow and not because of increased tube lengths allowed for better scavenging. I have little doubt that you understand this much more then I do, but I do understand the generalities.

I do appreciate that you typed that though.

Termination boxes are new to me in this context though. Could you expand on that?

[Dimman]

Originally Posted by Calum

What I said was meant to be a rhetorical question to point out the possibility that it was incorrect to make the assumption that the removal of the cat allowed for big gains because of the restriction to flow and not because of increased tube lengths allowed for better scavenging. I have little doubt that you understand this much more then I do, but I do understand the generalities.

I do appreciate that you typed that though.

Termination boxes are new to me in this context though. Could you expand on that?

It's for everyone, Calum. Just expanding a bit on what you post but then I get tech rambly...

Main thing is gains come from both, but everyone focuses on flow because it's easy.

A termination box is a container of fairly large volume that mimics atmosphere to the pressure waves. When waves reach it they diffuse and lose energy. So waves do their normal thing entering, but everything after it is irrelevant to acoustics. So you can tune the back half of the exhaust just based on flow. The power curve and acoustic gains are no longer affected by muffler designs, so you can usually get away with using smaller and much quieter mufflers with minimal power loss.

Started in competitive circle track classes when communities began introducing noise limits for the tracks. Allowed open side pipe tuning to be quieted down, but not choke power or change the curve.

Might not be enough room in the right place under the 86, though.

[Calum]

So infinite baffle to speaker guys... Interesting!