NorCal GOATs Mod Day

The JBA Shorty Headers have been installed! It was a long day of working on the car, but I’m generally pleased with the results.

On Sunday the NorCal GOATs had a Mod Day… it was really great to see everyone get together and wrench on cars! There was a constant stream of cars being works on… from header installs (3), fender grinding/rolling (3), ignition cylinder replacements, front splitter modifications, spark plug/wires, etc. There were over a dozen people working on things at various times. There was also a TV with football games and a great lunch.

On the way to the Mod Day a few of us met up at Stoneridge Mall and made the drive to Tracy via Patterson Pass. The road was great (as always) and made for lots of fun before a long day of work.

I got the G8 up in the air (I’m glad I had the experience from installing the Corsa Exhaust) and started removing the stock manifolds. The engine compartment of the G8 is a bit tight, so I’m really grateful there were some people with smaller hands to get into the tight spaces. After removing the stock manifold on the driver’s side we tried to install the new Shorty Header… unfortunately, there was a problem.

The header was not connecting up to the stock mid-pipe/catalytic converter… the bolts were not going into the flange on the header. We had to remove the mid-pipe, where we discovered that the header had not been properly machined. The holes the bolts go into were not elongated the same on both headers… so out came the dremel! After a little grinding everything fit right and we continued on the install.

Since installing the header to the mid-pipe was easier outside the car, we also removed the passenger’s side mid/cat (while others were grinding on the header). This side was machined properly so went very smoothly. Unfortunately, the driver’s side header/mid-pipe could not be installed as a single piece… this resulted in an exhaust leak when we first fired-up the engine. The leak was quite clear, but it took several different tries at fitting in different orders to get everything right. We even had to drop the exhaust on both sides to get things in right… but this resulted in an opportunity to hear what the G8 would sound like with no exhaust (it was nice)!

Once everything was back together and checked-out I put the car back on the ground and took her out for a test drive. The drive was a short one though, as after a few minutes the engine was acting really rough and threw a Check Engine Light (CEL). I also noticed a noise when turning the car to the right (much more on this in the future). Fortunately, someone at the Mod Day had a DashHawk and was able to check and clear the CEL… turns out there was a “cylinder 2 misfire” caused by a loose spark plug wire. Once it was plugged back in I took the G8 out for a serious test drive.

I don’t know if there was any ‘seat of the pants’ difference with the headers installed, but there is definitely an audible one. The G8 is actually QUIETER now. The sound is much more even… very refined. The car is mild at idle and low RPMs, but still screams at WOT… just what I wanted! I think the ECU tune, that was designed for running the headers, was not at homeostasis with only the exhaust installed, resulting in the louder sounds.

Once my car was wrapped-up I had some more time to talk with some of the other people at the meet. It was really great, lots of information about all sorts of stuff from smog checks to photography. The night wrapped-up and I headed home (and actually made it without any major issues).

Huge thanks go out to those who helped wrench on the G8… I would have never been able to do this by myself!