Another one. Exhausted

[monstar]

So to sum up ^^^^

4-2-1 = more beneficial in the rpm ranges the engine will spend 95%+ of it's time in a daily driver, might not sound quiet as good as the 4-1, then again might sound better.

4-1 = better if you have a 4000rpm converter, big gears and drive around with your boot planted 90% of the time with potentially more ground clearance issues.

No see video below drag strip 4500 stall 4-2-1, I’m saying 4-1 is narrower power peaking up high, but area under line past torque peak not better vs 4-2-1.

I don't think you can compare pacemaker style 4-2-1 headers Vs NASCAR headers. Yes they are both 4-2-1 but totally different when it comes to primary/secondary lengths.

NASCAR headers are a piece of art all by themselves.

R07 vs LS3 peak output is the main difference, hence ~1 4/5” OD vs 1 3/4", otherwise about same length per equal length primary section, 17” vs 15”.
View media item 401^^ Pfadt make a set for the Camaro LS3 almost identical spec to R07, Rick Crawford has a set of these on the World record NA Zeta 1 7/8” primaries 3.5” megaphone out. Like NASCAR.

My headers are tuned for different fuel, lower peak hp, so 1 3/4” primaries otherwise same dimensionally including 3.5” megaphone out.
Race setups have shorter mega and secondary than ideal for LS3 daily due to high RPM peak vs full range torque.

 

[426Cuda]

Thanks for the awesome responses guys.
Who else in Oz makes long tube tri-y's other than Pacemaker and Genie? Does Manta?

 

[GMVPSS]

So to sum up ^^^^

4-2-1 = more beneficial in the rpm ranges the engine will spend 90%+ of it's time in a daily driver, might not sound quiet as good as the 4-1.

4-1 = better if you have a 4000rpm converter, big gears and drive around with your boot planted 90% of the time with potentially more ground clearance issues.

I don't think you can compare pacemaker style 4-2-1 headers Vs NASCAR headers. Yes they are both 4-2-1 but totally different when it comes to primary/secondary lengths.

NASCAR headers are a piece of art all by themselves.

or an Australian pro Stock Tri-Y header tuned for 10,500rpm on a 400ci small block.

 

[GMVPSS]

Notice how short the primary pipe are for a 400ci motor. Shorter for more RPM capability.

 

[Not_An_Abba_Fan]

What are wanting from your car? No point in theorizing and calculating then comparing unless you have a goal in mind. Match the headers to how you want the car to perform, don't try and find the headers that are best in theory.

You are spot on in what you say about there being a bees dick difference when it comes to how they perform, they are all very similar, personally I like the 4-1's as they have a longer torque curve and sound better.

Manta don't make any headers, they use a variety of brands to suit applications. They use Hurricane on the VE-VF.

 

[426Cuda]

Thanks NAABBAF, LOL.
I understand what you mean. I'm not looking for the big high end number. What I'm looking for is throttle response, low and mid range torque and finally a nice note. Deep is good.
I realise some of those criteria lend themselves to long tube 4-2-1, whereas the note probably more so 4-1. Ill check out the Hurricane range.
I really appreciate the input, both here and in my PM you responded to.

 

[monstar]

I'm not looking for the big high end number. What I'm looking for is throttle response, low and mid range torque and finally a nice note. Deep is good.
I realise some of those criteria lend themselves to long tube 4-2-1, whereas the note probably more so 4-1. Ill check out the Hurricane range.
I really appreciate the input, both here and in my PM you responded to.

4-2-1 design is all about tractable torque, complementing the uneven firing order of the Big Bang cross-plane crank.
Most notably this design is the top optional offering for the LS7 NA COPO engine, but perhaps the best recent example outside LS verse is at the bleeding edge of race engineering Moto GP racing.
The class leading YZR-M1 inline 4 introduced the benefit of near zero inertial torque offered by a cross-plane crank, in practical terms the tractable torque enabled the bike class dominance attributable to pulling out of fast corners.
View media item 403View media item 402The purpose of Big Bang cross-plane engines is to eliminate high frequency torque fluctuations, the uneven firing intervals are a side-effect, not the objective. The YZR Big Bang pipe design of Moto GP, and what we call tri-y in LS COPO and NASCAR is to correctly scavenge uneven pulses, rather than have them not work for much benefit at all then come together briefly at a high RPM peak.
Flat plane crank '70s mini-van or sports road bike = 4-1.
Cross plane crank modern V8 muscle car or race bike = 4-2-1.

 

[426Cuda]

4-2-1 design is all about tractable torque, complementing the uneven firing order of the Big Bang cross-plane crank.
Most notably this design is the top optional offering for the LS7 NA COPO engine, but perhaps the best recent example outside LS verse is at the bleeding edge of race engineering Moto GP racing.
The class leading YZR-M1 inline 4 introduced the benefit of near zero inertial torque offered by a cross-plane crank, in practical terms the tractable torque enabled the bike class dominance attributable to pulling out of fast corners.
View media item 403View media item 402The purpose of Big Bang cross-plane engines is to eliminate high frequency torque fluctuations, the uneven firing intervals are a side-effect, not the objective. The YZR Big Bang pipe design of Moto GP, and what we call tri-y in LS COPO and NASCAR is to correctly scavenge uneven pulses, rather than have them not work for much benefit at all then come together briefly at a high RPM peak.
Flat plane crank '70s mini-van or sports road bike = 4-1.
Cross plane crank modern V8 muscle car or race bike = 4-2-1.

Fascinating read!

 

[lmoengnr]

Hey Monstar, what's the redline on a YZR-M1?
How does it compare to the redline on an LS?

 

[monstar]

Hey Monstar, what's the redline on a YZR-M1?
How does it compare to the redline on an LS?

Don't know, motorbikes usually rev higher than cars don't they? Don't know how to take most of your questions frankly @imoengnr. Either you're straight up, plain and simple or a cagey HSV (better badged) troll.
Anyways I think the closest comparison is contained per my post immediately above where dimensions for GM (Holden) V8 Supercar entries using R07.2 engine sleeved to 5l at 10:1 CR and limited to 7500 RPM is a closer comparison.
Header design is same as tri-y street headers with differences noted.