The real problem I have seen with aftermarket exhausts other than not being drilled out, are that the flanges are both welded to areas that see the same amount of exhaust pressure.? If you notice the stock mufflers ran a pipe down to a low pressure area so there would actually be a flow of exhaust through the intake preheater runners.? Not sure how much flow you get through even if the holes are drilled out.? Anyone know?
Ray -----Original Message----- From: Brian <[EMAIL PROTECTED]> To: [EMAIL PROTECTED]; Air-Cooled Volkswagen Discussion List <vintagvw@lists.sjsu.edu> Sent: Thu, 20 Nov 2008 5:08 pm Subject: Re: [vintagvw] 1600cc Single Port Greg, I still use a 009 distributor with the H30/31 carbed 1600cc engine that came on my '65 convertible since it does not have the off-idle hesitation. However, I removed the 009 that came with my 1500cc 30-Pic-1 carb equipped enginge on my '67 Ghia. I replaced the 009 with a stock distributor and the hesitation almost disappeared. There is one other thing thing that contributed to the hesitation on my Ghia (see below). Someone else has already described the importance of ensuring the preheat tubes on the intake manifold are clear (not blocked). As you know, the end of the preheater tubes are bolted to flanges on the exhaust. If you are using an aftermarket muffler, look into the flanged hole to verify that a hole was drilled into the exhaust pipe. I removed the aftermarket muffler from the Ghia to find that the hole was not drilled; therefore, no heat was transferred into the preheat tube. I'm not sure why they'd go through the trouble to weld the flange on the exhaust and NOT drill a hole into the pipe! Good Luck! Brian ----- Original Message ----- From: "Greg S Tipton" <[EMAIL PROTECTED]> To: <vintagvw@lists.sjsu.edu> Sent: Thursday, November 20, 2008 12:27 AM Subject: Re: [vintagvw] 1600cc Single Port Hello Brian, Thank you for the information. I now understand why the 009 stumbles. I enjoyed reading the articles and I now have a greater understanding of how the two types of advances differ in performance. Another plus is that I now know what is wrong with my Dad's 72 Super Beetle. He also has a 009 distributor. I do not understand why anyone would put the 009 on the car if it has so many problems. By what I read it is more of a step backwards in perfomance rather than enhancing performance. take care, Greg Brian wrote: > Greg, > > The vacuum advance works to advance the ignition timing based on > engine load > (the more load (vacuum), the more ignition advance). The centrifical > advance > distributor (009) advances based on RPM. There are weights attached > that advance > the timing at increasing RPM. With the 009 you may notice flat spots > on acceleration > because the timing does not advance at low RPM. Here's a good > description of the > distributors: > > http://www.vw-resource.com/009_history.html > > There are a few of things you can easily check on a used vacuum > advance distributor > to determine it's condition. > 1) The lobes on the distributor shaft should not be too worn. > With the distributor cap removed, try to wiggle the distributor > shaft side to side; > there should be very little noticeable movement. > 2) With a hose attached to the vacuum canister, suck on the hose and > watch the advance > plate inside the distributor rotate (advance) slightly. > 3) There should be a small braided wire (ground) attached to the > advance plate on one end and a > nut on the other. The nut is held to the inside of the distributor > by a screw from the outside. > If you need a picture of this, let me know. > > Here's more good information regarding different distributors. > http://www.type2.com/~keen/ignition.html > > Brian _______________________________________________ vintagvw site list vintagvw@lists.sjsu.edu http://lists.sjsu.edu/mailman/listinfo/vintagvw _______________________________________________ vintagvw site list vintagvw@lists.sjsu.edu http://lists.sjsu.edu/mailman/listinfo/vintagvw _______________________________________________ vintagvw site list vintagvw@lists.sjsu.edu http://lists.sjsu.edu/mailman/listinfo/vintagvw
