[javadog]

When the Carrera tensioners came out in 1984, they were considered bulletproof, and the final solution to the problem. Years later, with a little experience, we know that they can fail. Porsche had partially solved the problem a few years prior, with some other changes they made. Nowdays, you'll find more than a few of the top engine builders using another solution. Research it, if you want.

As for the airboxes, Porsche made yearly improvements to their CIS systems and the biggest step for the 911, as far as blowing up airboxes was concerned, was the introduction of the later style box that had the improved cold start fuel distribution manifold. I've owned at least a dozen CIS-equipped cars and have yet to have a single problem with an airbox. I think you'll find that by 1983, there wasn't much need for a pop-off valve, unless you were the type of owner that didn't service a car regularly and let things deteriorate to the point of not running before fixing things. I think Pete Zimmerman wrote a piece on why he doesn't like the pop-odd valves. You should look for it and read it.

Porsche installed halogen lights in their US cars in the 1980's. I have a bunch of them sitting on a shelf. GE, Wagner, etc. What you see as an improvment in an H4 or H1 isn't the type of bulb technology used, it's the design of the entire light. The DOT mandated sealed beams for the US. The H4 and H1 lights weren't sealed beams. They were never legal in the US. The lighting standards have since been relaxed and nobody ever cared, really, if you changed the lights. The local police didn't really know the difference. The improvements come from the optics of the light. And, there are trade-offs, which is why the US used a sealed beam light for so long. One seldom-mentioned aspect is the light distribution. The US wanted more of it directed above the road than the Europeans, the better to illuminate the road in dips and to illuminate the overhead road signs, like on an interstate. I've run H4 and H1 lights for decades and there are a few instances where I find them lacking. Choices...

I've never liked third brake lights, as they often interfere with my rear view of the road. The only time I was rear-ended, it was in a truck with a third brake light. Ironic, no? Some people just can't drive.

The advice I was giving has more to do with hindsight, than anything. I have loads of documentation of techincal issues related to Porsches, going back more than 3 decades. I find it humorous at times, to go back and read what was the common wisdom in days past. Straight weight motor oil was mandatory, not the multi-weight oils that came later. Strut braces that kept your front strut towers from collapsing inwards under cornering, never mind that later it was figured out that they moved the other direction. You get the point, I hope.

JR