So this question has been going through my head, I've been trying to do all the research I can to figure it out and I just can't seem to come to any sort of valuable conclusion. The obvious answer to best headers are long tube which makes sense due to the removal of test pipes. What are better in this case, shorty + test pipes or long tube headers. If anyone has dyno numbers please share

The only reason why this question matters to me is I have to deal with emissions every couple years, so if both make about the same torque I'll gladly just go for the shorties + test pipes out of convenience

 

I’ve heard LTH will make better low-end torque due to them improving the scavenging effect. I’m assuming the convenience part is swapping the cats back in when it’s time for testing but I’d recommend looking into a mini cat like this https://www.urotuning.com/products/f...UaAgeFEALw_wcB

 

This thread post off G35Driver is a really good comparison of shorties vs longtube

Guy compares PPE's design of stepped and non-stepped designed vs momentum headers with Motordyne art pipes (z1 headers)

The DE seem to like non-stepped design. The HR/VHR are a stepped design.

He makes 21 whp and 13wtq peak gains over the shorties.


I was also at one point considering PPE headers or Z1 headers and I asked this forum member over at The370z.com since he's ran both.

 

Were those gains in comparison to the headers+test pipes? Where the gains are only from the type of pipe and not from the removal of the cats?

 

It was momentum headers + motordyne art pipes vs PPE headers. He also does stepped vs non-stepped on his cammed DE

https://g35driver.com/forums/intake-...ml#post6429229