progressive weber, running like crap

Since both carbs give the same results, I doubt it is the carbs. If the engine sat for two years, maybe it is fuel pump related.

Check to make sure the distributor advance mechanism moves ok.

Those carbs are next to impossible to tune for the VW engine, with the manifolds that are readily available. They need a totally different intake design. One you would have to fabricate yourself. And you'd still have too long intakes for that carb design.

They need to be jetted too rich for them to work acceptably throughout the rpm range. And the distributor curve needs to be tweaked, as it does with every 009 out of the box. ;)

Can you explain a bit how to check it? Last time I checked timing, I verified that it was advancing, but I didn't pay particular attention to the advance curve. Looking inside of it, it looks like I'd have to do a bit of disassembly to get into the mechanism.

The thing that gets me is that I believe this carb, distributor, and engine were all working together acceptably well at one point. There was always a bit of a flat spot, but nothing like what I'm experiencing now.

Thanks for the advice, Scott

How old is the gas in it ? All cylinders firing ? What's the timing set at ?

If the timing advances when you rev it up, the basics are ok... still, with the engine off, pop the distributor cap off and turn the rotor by hand. It should turn (a little, like less than 1/8 of a turn) one way against spring tension, and snap back when released.

You can oil the shaft from the top and spray lube the weights too through the points mounting plate. Don't get ANYTHING on the points themselves.

I drained all the gas and replaced with new before starting. As far as I can tell all 4 cylinders are firing (manifolds/exhausts equally warm, plugs show similar color). Timing should be in the neighborhood of 30 degrees maximum advance (it's been about 2 weeks since I last checked it). Certainly not more than 30 degrees, if anything a little less. I'll have to double-check to be sure.

Thanks for the tip, I'll check this.

One bit of information -- I'm *not* using manifold heat with this setup. The very first engine I used a progressive with may have had it, but this particular buggy never has (it has an off-road tri-mill type exhaust). After reading some of the information at aircooled.net, I'm finding the manifold heat sounds like it may have been more important than I'd ever given it credit. I'm still certain that I had the engine running acceptably (albeit with a bit of an annoying flat spot) without heat and with the current jetting, so there's got to be something additional going on. As it stands now, it's flat out undriveable.

Scott

What kind of intake manifold are you using? Does it have heat riser pipes? If so, are they clear, and is the header drilled to send exhaust through them?

Without adequate manifold heat your Weber will ice up. BT, DT, got the t-shirt. Intake icing causes all kinds of odd driveability problems, especially if the humidity is high.

I never had much luck with my progressive weber. In my case the biggest problem was my intake manifold was a total piece of shit. And I had a -009 distributor, which was strike #2. That was enough to make my bug a semi-drivable pile of manure.

Things got a whole hell of a lot better when I junked the Weber and went back to a stock intake, stock 34pict-3 carb, stock exhaust system, and a vacuum advance distributor. In my case, it was the difference between night and day once the work was done.

Good luck with it,

Chris

John Aircooled.Net Inc.