2.5 NA Exhaust Clearancing

[phil1734]

Since I finally made a user name and most of the 818 knowledge here is lost in build threads thought I'd start dumping what I've learned (particularly because I'm seemingly 1 of around 3 that have a naturally aspirated 818.)

First off - my exhaust didn't fit well at all. This is a '03 2.5. I surface ground ~.010" total off the spacers but was was short of the FFR pipe clearing the chassis. Emailed FFR support and they quickly sent out additional spacers/gaskets to drop everything another .5 inch, which was just enough.

Then when I thought I was in the clear the body work came up and needed some trimming around the cat, as well as a few rough pie cuts to bend the "tip" down (keep the pie cuts as close to the cat as possible to maximize the bend.) Note that none of this is visible while viewing the car from any angle other than the ground.

NCM_0231.JPGNCM_0232.JPGNCM_0233.JPG

Long term plan is to make a set of extended headers that don't require the heavy, clunky spacers and straighten out the exit since it sits at an awkward angle, but it's hard to build an exhaust when the car is stuck on jackstands 30 miles from the welder.

[DSR-3]

Thanks for posting. I had no idea that the spec NA routing was under the chassis.

[THE FURNACE]

There must be enough room to route the exhaust over the chassis, isn't there?

[phil1734]

There is plenty of room without that pesky turbo in the way for just about anything back there. You'll need custom headers since the FFR tube frame is in the way of the formerly swoopy, curvy OEM subframe (probably why FFR didn't do it from the beginning.)