jteran5

I wanted to get everyone thoughts on this. I just ordered an HKS single exit exhaust (31008-BM002). The catback is 85mm but has a stock inlet that enlarges to the full 85mm after about 2in in length. I currently have a 3" ETS test pipe. I don't want a "bottleneck" within the exhaust so should I:

1) cut and weld a 3" inlet and have it enlarge to 85mm, similar to the Driven Fabrication Titan single exit
2) cut and weld a 85mm inlet and just have it bolt up to to the3" test pipe with no transitions and just run an 85mm gasket. Not sure if there would be any downsides to this. flow is only going one way so even without transitions, I should be okay?

I don't see many people running this exhaust. I know Kaizen Tuning used to offer a 3" inlet modification to this catback but they have since closed down. I got a quote from a shop for the custom fabrication and install, it would be $300. Does this price seem decent?

AF13_Evo

Seems like a waste of money... Why not just go with a STM single exit and call it a day? You're spending an extra $300 when you could use that money on something that is made for the application.

jteran5

I prefer the look of an n1 can. And I got the HKS for a stupid low price of $420 NEW so it was a no-brainer for me. Just need to work on the inlet option.

six40

I would personally do a 3" (76mm) flange and then a smooth transition to the 3.35" (85mm) pipe. That way you can use a standard 3" gasket, and have a much higher chance of having a perfect seal. The smooth transition from 76 to 85mm will also help reduce turbulence as opposed to just having a big step.

You can realistically do it both ways, but the way I mentioned it the better of the two (I believe). Definitely jealous of the HKS single exit though. Post some pics/videos when it's all said and done!

jteran5

Thanks. I guess I will go your way. I could have picked up additional 85mm gaskets from HKS but I might as well just stick with a 3" inlet so everything transitions smoothly.

I got the exhaust already and it looks absolutely stunning. I'll try to take some pics of just the exhaust but it won't be installed for another two weeks or so. I am still waiting for the Group N exhaust bushings to have everything done at once. The vendor I ordered from said he should be getting them sometime this week. Then I still have to wait for shipping to the US.