/it was just some amazon gold reflective tape. I forget the exact brand.

They downgraded the design to use cheaper components, pre-bent piping, smaller flanges, etc.

Basically, all of the feedback from CSG that resulted in the Ace header continuing to evolve was mostly undone.

Old header (not the latest/best version) vs current Ace header.

https://d2j6dbq0eux0bg.cloudfront.ne...1031667471.jpg

https://d2j6dbq0eux0bg.cloudfront.ne...1031667441.jpg


The performance is NOT the same, and very visible on a dyno.

Can you show us the difference on a dyno?

Source: trust me bro.

I have reason to trust Mike as CSG is the main US retailer for the ACE headers, as well as all the testing and experience they did with them.

I was deciding between the Ace350 and the JDL 4-2-1. Performance wise it's really splitting hairs (that being the old design Ace BTW) so buying a product made in the USA vs one that's not, and saving several hundreds of dollars made the choice easy.

Then again maybe if I was planning on staying NA and really wanted to squeeze every ounce out of the FA20 I would have thought a bit harder about it. Probably come to the same conclusion but it would give me pause

Since someone asked... (this is not my image) This is a later iteration of the A350, but a few revisions before the current.

https://www.trackjunkies.org/uploads...7e912298c3.jpg

I'm looking into replacing my Tomei EL and OP with this one. Ace told me that they have not yet shipped a single unit of this version.


They also told me that stiffer engine mounts and ceramic coating are not needed with this version, but that it may contact the skid plate because of the length of the runners. But the OP should not contact the engine cross member under load/in cornering.

I haven't had issues with any of that with my cs400. Just a single data point

Yeah, I severely doubt a slight increase in bend radius of one part, and a slightly thinner flang material (reportedly) is showing up on a dyno. The tension of the hold down straps would likely make a bigger difference.

If it's true that Ace hasn't yet shipped one unit of this version, it seems the only way anyone could know how it dynos is if they were privy to the results of pulls that Ace themselves have done with it.


I asked Ace for a dyno plot comparing it to stock, but didn't get a response on that. I'm leaning towards taking a chance on this version, based on previous versions' ability to fill in the torque dip.


I'll report back after I've broken in a tune on it and have had it dyno'd.

Are people still trying to get the ACE exhaust in 2022? It offers similar if worse performance than the JDL unit, with higher chances of cracked welds, you basically need engine mounts with it, and it costs SO SO much more if you can even get one.

tl;dr

The "new" A350 is the old "RHD" unit.

Perhaps they haven't shipped it under the new labeling, but I'm an equal opportunity truth dealer, and well.... yeah. These are out there, maybe under the old label.

ACE does outperform the JDL.
You don't need better engine mounds with it.
Cost is the reason they stopped supporting twin owners, because most are cheap.
Welds cracking is not unheard of with any other brand.