Ok, so I have to study the instructions that came with my Pertronix billet aluminum distributor. It has a fantastic "module" built in, the Ignitor III, which provides TRUE multiple spark output, a rev limiter, and high voltage spark capability when paired with the Flamethrower ignition coil.
The unit came with springs and weights, and some other parts to tune the timing curve and advance to be of greatest synergy with the engine it's installed in. I haven't done anything with it since it was installed. The shop that installed the 421 after the rebuild had "issues" with the vacuum advance, which I have hooked up now because most of the time the GTO is cruising around, going to local car events, and I'm all in on the benefits in efficiency that a vacuum advance can bring.
To his credit, Mr Boneske recommended that I disconnect the vacuum advance at the race track and set the total timing to about 33° I chose to disconnect it to do the total advance, but reconnected it for the trip and left it connected when I made my runs, because at WOT there is very little to no vacuum. What I did notice is the "sputtering" and "surging" sensation in the background of the main feel coming from the engine that I thought was carburetor related because it was gone when I installed the modded carbs I got back from Boneske, well that stuttering was back on the road and highway there and back.
So I think there is a lot of room for improvement in the overall performance and race track performance of the 421.
So now that I've prefaced my "track night report" I will say that the GTO is running better than ever, and the 4/10ths better than ever times reflect that. I also used the line lock for the first time, cleaning and heating the Toyo Proxes TQ drag radials in 2nd gear which seemed to give me enough torque and wheel speed to get the job done. I also did "no lift shifts" tonight, relying on my rev limiter should I miss a shift. I ran 13.6 @ 103 and 13.58 @ 102 No wheel spin on the first run, and a little on the 2nd. I don't have a tachometer, but the soon to be installed Dakota Digital gauges will remedy that, and the control box will allow for a shift light too. On each run I found the rev limiter in 2and or 3rd. Also, the combination of tire diameter on the 17" wheels and the 3.80 ring and pinion gearset make for a very high revving combo. I was concerned about hitting the 5,800 RPM limit in 4th, and I'm sure I was close, but I didn't hit the limiter on any run in 4th gear. The TKO600 5 speed is a MUST with my current combination on the highway, but certainly not at the track. If I find that as we get quicker off the line and down the track that the limiter in 4th is an issue, I may bump the limit a bit or find a taller tire.
Overall I'm very pleased with the performance of the GTO, and very pleased with the work and modifications Mr Boneske did, and the car is running better. I have jets for all 3 Rochesters in the next size up and down from what Boneske installed, so I have some tuning available there. Before I consider rejetting though, I need to get the distributor squared away.
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