Your stock exhaust manifold revealed

[pepe]

I have thought of buying uel catted JDL black coating. is wasting money?
risk of fire?
Thank you

[steve99]

Originally Posted by pepe

I have thought of buying uel catted JDL black coating. is wasting money?
risk of fire?
Thank you

Thousands of people running aftermarket catless and catted headers on NA and turbo cars without heat shields and not coated.

heat shields and coating likely reduce under bonnet temps in slow driving or heavy traffic but once you get up to highway/track speeds their will be plenty of airflow to cool things

The only fires i know of have been due to leaking fuel lines usually on crappy aftermarket flex fuel kits.

[Zentec]

So are the stock headers equal or un equal length on these cars?

[Cole]

Originally Posted by Zentec

So are the stock headers equal or un equal length on these cars?

You saw the pictures in the second post, right?

[mrg666]

Originally Posted by Zentec

So are the stock headers equal or un equal length on these cars?

It is approximately equal.

[Zentec]

Yes Cole I saw the pics the center ones looked shorter and the outside ones looked longer I couldn't tell that's why I asked.

[Clipdat]

Indeed, the OEM 13-16 exhaust manifold is slightly unequal. That's why with certain exhausts at certain RPMs, you can hear a hint of boxer rumble.

Originally Posted by Zentec

Yes Cole I saw the pics the center ones looked shorter and the outside ones looked longer I couldn't tell that's why I asked.

[Zentec]

Indeed, the OEM 13-16 exhaust manifold is slightly unequal. So the 17s are the same? Or did they up grade them.

[Zentec]

Originally Posted by Clipdat

Indeed, the OEM 13-16 exhaust manifold is slightly unequal. That's why with certain exhausts at certain RPMs, you can hear a hint of boxer rumble.

Did they change this on the 17s?

[Clipdat]

Not sure. I don't recall seeing a 17 manifold w/o the heatshield. I've also never driven a 17 w/ an aftermarket exhaust.

Originally Posted by Zentec

Did they change this on the 17s?

[WNDSRFR]

I'm the guy who started this conversation and after all these years I have to say that I never wrapped the OFH like I mentioned. I was just a little paranoid at the time.

But I'm happy to report that after 110,000 miles of auditory bliss, there have been no problems what so ever.

[Zentec]

Has anyone taken off the stock headers on a 2017 86/brz. They are said to have re designed them on the manuals to get the 5hp and 5trq bump. If so can you post some pics.

If you upgrade the headers do you have to upgrade the over pipe for a n/a application?

[gtengr]

Originally Posted by Zentec

Did they change this on the 17s?

According to Subaru they are equal length on the 17's. The primary diameter went from 42.7 mm to 45 mm, collector shape has been optimized, and the pipe size after the first set of collectors has been increased from 45 mm to 48 mm.

[churchx]

They still have cat that close to cylinders for sake of cold-start emissions and imho not exactly optimal for best scavenging runners length (compering to ones like Nameless/Ace). So it's just very slight improvement over older stock headers.