Help me choosing between these two manifolds
 

I'm really debated between those two manifolds, I'll not post the brand for more impartiality. Both of them are 4-2-1.
What do you suggest and why? Thank you!
https://i.ibb.co/yNp92jN/img-2400-1-1-600x.webp
https://i.ibb.co/w4dWHMR/P1310665.jpg

The merge looks nicer on the bottom one but wdik?

Whichever has a history of preforming the best.

I'm not an expert on header design, but this page looks like it has a good discussion on header design considerations: https://www.enginelabs.com/engine-te...gn-and-theory/

The main difference between the 2 headers you posted looks to be the length of the primary runners. I'd suggest researching that aspect of the header design.

From what I've seen the longer runner style header is what gives this platform better performance - Think Ace, JDL, Nameless, P&L all longer style runners giving great numbers. I'd go for the bottom set

That's what I read, anyway, while the second one in all the dynos I found gives a great result at high RPM, but a little loss of torque under 3000 RPM, the first one seems the opposite.
Both use 45mm primaries.

UEL because it sounds like a true Subaru

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The first one looks like the prev gen ace which was the best. It's a 4-2-1 while the bottom one is 4-1. The way the latter looks is it dissipates too much heat and hence all the insulation even below the oil sump.
I will go with the former not the latter.

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Look closer, they are both 4-2-1. One should run insulation on the oil pan regardless of header design.

EL, because I own a Toyota! :-D

Well that would be the first one then but UEL sounds more cool.

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Ehm, not my taste, it sounds like an Harley...

Then I guess you have your answer, you're welcome.

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Well the top one is HKS and it's a decent header. I'm not familiar with the bottom. But I'm sure either or will only net very little difference.