HKS EL vs ACE 350 Dyno Comparison
 

There is a post in the Naturally Aspirated 86 FB group right now where someone has dyno'ed the same car with an HKS EL header against the almighty ACE 350. Both headers have a custom EcuTek tune done by an experienced tuner. All conditions are the same (ambient temp, fuel, etc.) Here is the graph:


https://i.imgur.com/j5UqxtF.png


The top line is actually the HKS EL, not the ACE. Needless to say, this is not what anyone would have expected. There is some discussion that the tuner does not know how to tune for the ACE, but the tuner is claiming they have spent several hours on this and can not add any more timing.


The only other real head-to-head ACE header comparison out there is the one @justinco posted here back in 2018. He compared the Revworks UEL against the ACE 350 with the same conditions and everything. The ACE performed noticeably better. I think the Revworks is a fairly typical UEL design so you could expect it to perform about the same as the Tomei, JDL, Gruppe-S, etc. These are @justinco's numbers for the Revworks UEL vs the ACE 350:


https://i.imgur.com/ssu7Xlb.jpg


What does everyone think? Is the HKS EL the new king? Is there some secret the tuner doesn't know that is necessary to unlock the ACE 350's full potential?

I doubt it

I am skeptical, too. I am wondering if something else happened to the car between the install and dyno runs that caused a power loss.


I am curious what some experienced tuners for this platform have to say regarding the numbers they have seen with the various headers out there.

THIS IS JUST MY PERSONAL OPINION: I didn't try the ACE Header, but I saw many dynos that shows that ACE is not a miracle, especially if used with high octane fuel.
In Japan, nobody uses ACE, but HKS or Fujitsubo (the new EPU exhaust with EL long pipes).
On paper, 42.7 mm long primaries should give more torque at low rpms, but sacrifying high rpms against 45 mm of the 2017 headers. Very long secondaries should give good mid range torque.
With ACE, I expect a little more on high rpms, but not as much any classic EL header, almost same low end torque of stock >2017 header and almost no mid range torque hole.
Does this justify the cost? In my opinion, no.

Too bad the Fujitsubo is only available as part of the $3K EPU kit. The HKS is looking pretty good for about $600.

Let's be clear: The guy pushing HKS is an HKS fanboy. The entire car has HKS parts. He sells HKS parts. He owns the company he linked too and omitted that fact.



At first he claimed he did zero tuning in the comparison and is now changing his words.
He has an axe to grind and products to promote. I just don't trust him.

Yes... I found another interesting EL long pipe header, it's the Toda Racing.

On this note, what are some other EL long header comparisons out there? I remember nameless made one some time back, but it's been discontinued for some time.

The elephant in the room that needs a 100% direct comparison is the JDL 4-2-1.

Headers are overrated in this particular platform. I wonder what is the gross margin of an ACE (Taiwan made) header ...

I'll vomit if I look at one more fucking manipulated dyno graph. The legitimate dynos get picked apart by the buzzards who claim they can do better. My extrapolation tells me that nameless and ace are best but by how much on a given day is the question. If you have access to e85 you can circumvent all header arguments

I second E85 being the equalizer. Its the biggest reason I question his results, it should have made equal power at the very least. He isn't the only tuner known for favoring a particular brand while down playing another *cough ACE vs old JDL EL*. Anywho, Tomei vs ACE on E85. We all know which shape is which by now.



https://i.imgur.com/sqRcnXF.jpg

Also what i recall from history, Ace performed poorly with stock tune and with generic OTS tunes. Only when DT invested lot of time to dial specific tunes, it started to shine. Experienced tuner? Maybe. But had he as much time/resources on spending as much time (btw, dyno time is expensive) to properly produce optimum tune instead of doing generic timing/fueling tweaks to more generic base tunes? Tuner claimed having spent several hours? DT worked for more then month and insane amount of dyno runs.

I mean, with my ACE CS400 I only made 176whp and 145 wtq. Still, when I had my HKS header on it felt satisfying. But the ACE "felt" better. As mike from CSG said, it's how the power curve is on what you feel. I still feel that my old Cossie header made the best up top but nothing down low. Either way, you're also comparing a header which is literally $1000 more to the HKS. I think the HKS does good enough. And as @nikitopo said, headers can be over rated. I've seen enough on here saying just to gut the stock header to believe there is something true to that.