dual weber carbs reply

[scriabin]

Hello all brave 914 owners--

Just one more note I feel should be spoken, as I have not seen it metnitoned in this list: SPARK PLUGS are your Oracle at Delphi, your sage and guru on the mountain. If you have carbs and are 'twiddling' towards better performance, you MUST consult your plugs. They will tell you what you need to know about what jets you need at least as well as your seat-of-the-pants driving intuition. I spent two months properly dialing in a set of dual Dels (so that I would never have to touch them again) and the plugs always gave me the straight answer on what I was doing right and wrong. You need to give consideration to all of the parts in you carbs when seeking a balance: the size of the venturis, pump jets, idle jets, main jets, and air correction jets. All these depend on the size of your jugs, the size of the valves you chose, and the amount of work you had done on your heads, if any (unshrouded, ported, polished, etc.). The needle valve travel distance also, to note, which determes amount of fuel available in the float chamber. Dels offer a great selection of emulsion tubes--my stock ones were perfectly suited though--but I don't know about the selection on Webers, sorry.
Also, know your plugs. Stick with Bosch copper and you'll be just fine, W8CCO for example, or the hotter W7 if you are into an high performance arena using more fuel, or in a very cold climate.
As for the distributors, I've tried the list: 009 is Blah, the range is narrow (very limited advance) and does peak quick, thus good for low end driving, Beetles and Bugs, but not for over 3000rpm driving. The 050 has a more consistent, or 'flat' curve-- typically, usually, just reaching to 27 degrees. It's a good distributor. My favorite is a 914 original though, with the mechanical advance and vacuum advance hooked up. There's no connection for the retard line on carbs, but even my dual Dels have the advance port on the passenger side carb. With a little modification I made my distributor push past the 27 degrees mark, and my 2.2L has maxed out my 120 speedo on the interstate without a single ping.
And know that even with help on the net, you should still own a carb manual for referencing.
P.S. Put some anti-seize on those plug threads if you are going to be checking them so often. And I've found just stiffly hand tightening plugs into the heads to work reliably. I've never put a ratchet to mine, installing or removing them. Anyone got an oppinion on that? just holler back.

[Conrad W Peden]

Amen on the plugs item. I've replied to the carb questions in the past and totally forgot to mention that. I suppose I took it for granted. I have Dells on my 72 1.9L, medium cam, 10 to 1 compression , exhaust was custom 1.75 inch from each cylinder into two 2 in. pipes with a Turbo muffler on each pipe, and I wish I had the original dist. but am using a 009 now that the motor is tired after three years of autocrossing and hard daily driving.
1.9L?!?!? Yeah, its a 96mm big bore kit on a 1.7. Works out to 1911cc.

Now that I think about it the plugs were what told the me the most about the engines diet during its life.

Anyways, you are absolutely right about the plugs

Later,
CWP