Quote:
Originally Posted by John V.
Jim, how long before you started massaging it? Would be cool, at least for me, to learn about the progression of things while the car was still pretty new (first couple years?), when you did them, and how much they helped. How long did it take to go from 13.90 to 13.05, were you still using it as transportation? Was that all with the 3.23 gears? Did you do the Bobcat mods? Stuff like that. Or did the mods come much later after it was retired from commuter duty?
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This will take some time to go through all of the details (and try to remember them correctly). I will also mention some of the problems/failures. For the first four or five years I did not do much to the car. It never had the Bobcat package, but later on it probably had something equivalent. I first raced it at San Fernando, which was at about 1000 feet and had bad air and traction. Absolutely bone stock (Red Lines and all), the best I could get was 14.90 at about 96. One day I borrowed a set of cheater slicks and ran 14.34 at about 97. This was the first year I owned the car. In late '64 I moved to the South Bay area of LA and Lions became my home track. The air was much better there, but the starting line was still a challenge with the limited tire I had. That's where the car ran 13.70 at 101.12, but it was typically in the high 13's. It was very inconsistent with the vacuum linkage as there was no "part throttle" to manage traction, but it ran as well as the mechanical linkage when you could get it to hook up. During that era I updated to the mechanical linkage, added an exhaust bypass in front of the mufflers, and I put in slightly larger jets in the tri-power. I never had the heads off, the distributor was not worked on (it had never been removed) and I did not have adjustable lifters. The valve train geometry was also bone stock, and lifters predictably floated at 5600 RPM.
In '68 or '69 I decided to do a valve job, which grew into doing the short block as well. I won't go over all of the gruesome details of that engine, but I made the mistake of believing what was in the hot rod magazines. I "improved" the car to 14.34 at about 95 mph. I later found out that a single pattern cam (Isky 280) was a mistake on a Pontiac, so I bought what I thought was a 744 cam directly from Pontiac. It turned out that they had the wrong cam in the box: it was letter "E" instead of an "H". Even with the upgrade to 3.90 gears, it ran no better than my first failed rebuild. By that time I was fortunate enough to run into a very knowledgeable Pontiac guy. I bored the block 0.040", got a real 744 cam, and did some minor cleanup to the 1968 #16 heads that I used. Real compression was still about 10.5. This was the configuration when it ran 13.05, and I think the MPH was about 105. I forgot to mention that my "hop up" also consisted of adding a Holley 3310 and an Edelbrock EP4B aluminum manifold. I then switched back to a tri-power ('66 version) - with no other changes - and ran 12.90. I'll continue the progression of performance improvements in later posts. One thing I will say is that after my first failed "hop up", I never made another improvement that did not better the performance.