I finished installing my spark plugs last night. I picked up spark plug #8 on the way home from work.The front two plugs on either side of the engine were no problem at all. The two plugs on either side toward the rear were a little more difficult. Getting the plugs threaded by hand was tough because of the lack of space in the engine compartment by the transmission tunnel. Recall the V-12 was a 60-degree vee while the Small Block Chevy is a 90-degree vee. This was the first time I noticed the difference. I was able to install the plugs with the engine sitting on the motor mounts however. Anybody remember the V-8 Chevy Monza? I heard stories that a guy had to lift the engine off the motor mounts to get the plugs installed. Not so here.
I then moved onto the air filter assembly. One of my Jag-Chevy sources said that an air filter assembly and plumbing from a late 80â€™s TPI Firebird would work on my application. With this information I purchased a complete TPI Firebird intake set up on e-bay. Last night I thought I would lay out the system and run a trial fit in the XJS.
The source was only part correct on the TPI Firebird recommendation. The elbow from the throttle body to mass air flow sensor fits nicely. The rest of the system downstream of mass-air-flow (MAF) sensor will not fit the XJS-SBC swap. The tube from the MAF to the air filter canister is too long, bumps against the A/C compressor and routes the air filter canister toward the front of the car, rather than toward the firewall. The air filter canister itself is too large to fit in the left front corner of the engine compartment. ATTENTION LUMPERS: When it comes to the air intake system â€“just buy the 90-degree elbow from the TPI Firebird.
I have ordered a K&N Filter, aluminum tubing and a coupler. This set up will keep the air filter inside the engine compartment. I had visions of a nice cold air intake using the TPI Firebird set up, but that dream will have to wait. When you consider that the V-12 drew air from inside the engine compartment, this is one area where I am not giving up anything I had before. Things could be a lot worse.