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  1. Factory Five Roadsters
    I give up trying to solve this myself. After installing new heads (AFRs), and being really pleased with the HP increase, I discovered that once-in-a-while, when putting a heavy foot on the accelerator, it will miss and sputter at about 4500 rpm. If I back off of the throttle a bit and then...
  2. Factory Five Roadsters
    Updated valve seal problem, more pictures Well, I was first going to ask if anyone has seen anything like this and had an idea as to where to start looking for the source of the problem. Since the engine was new (6000 miles now) the number 2 plug showed a malady that I've never seen before...
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