Re: Dual Weber Carb Set-Up

Howdy,

I am sure it has been covered a least a million times within these hallowed forum pages...But PLEASE bear with me ...I'm a Speedster Newbie. But VERY familiar with all things VW. My box stock 1600cc with single carb needs a little assistance breathing...And I know from experience that some dual Weber 34s will do wonders. It's been a while since I've "Weberized" a VW motor....like WAY BACK in high school! Has anything really changed? Are they still the carbs of choice for VW/Speedster replica owners? Any recommendations on who offers a nice "turn key" manifold/carb/linkage/air cleaner kit? Any guidance is much appreciated.

DB

Welcome to the maddness! On small engines I like the dual Kadron setup myself

Don't forget that it has to exhale as well as inhale.

Dean -

'Welcome to the Madness' - WRT the dual carb set-up, I've had dual Kadrons on my 1835 for years without a single problem. Reliable, bullet-proof and smooth-running with absolutely minimal maintenance. I have 95K Kilometers (about 67K miles) on this set-up.

As with anything else with these cars, these decisions are a matter of engine application and personal choice. Good luck!

Dean, what Jim said-you can't argue 67k miles of reliability.
Here's a link for Kadrons (and others); might give you insight.
http://www.lowbugget.com/help_section.html
They've got a good rep., are in OC, and will adjust your carb settings per your engine specs.

Dean,
I have a set of Solexs if you're interested. They have Empi manifolds on them. I had them on my old 1600cc set up before I replaced them with Weber 34's and I've since replaced THAT set up with a new engine. Lemme know.

Dean, I've been looking at the Weber 34's at CB Performance. The linkage is part of the air cleaner mounting assembly. Different than the 34's at Weber Direct. I haven't heard a lot of bad stuff about CB and there seem to be a lot of Webers out there. Kadrons are another option for a little more money and these guys have had good luck with them. I'm still looking. Pipe up if you find something. Good luck. Al

Micky. Was there a problem with the Webers or did you just go with a bigger engine? Thanks

Alan,
The Webers were perfect! They went with my 1600cc when Dale S. bought it. Yes, I bought a CB Performance engine.
I was having problems with my Solex's and rejetted and rebuilt them, and then still had trouble getting them dialed in. So I said screw it and went with the Webers. They cut back on power a bit but the mileage was much better. I highly recommend them for the 1600cc. Thats not to say the Kads and Solexs aren't great carbs either, I just had issues with mine, which in the end I think were the cheap ass Empi manifolds. I actually like the look of the Kads and Solexs better.

Thanks , Micky, you've helped with my decision. When I get some scratch in the "toy fund" that is the first order of business.

I had a VERY good experience with Solex PDSIT from aircooled.net, on an 1835cc for a sandrail install. First time I did some work for pay, BTW.

The Aircooled.net Solexes with an SVDA is a nice choice IMHO.

Actually, the more I read about 009 Distributors, the more I long to try an SVDA.

I'm looking for a way to adapt my CB/Dellorto manifolds to an SVDA set-up like I had on my 57 Beetle sedan with dual Solexes (I ran a manifold equilizer tube) so I can run an SVDA disti to overcome the dreaded mid-range flat spot. That's for later this Spring - we'll see.

gn

That's just what I was gonna do but opted for this:
http://www.pertronix.com/prod/new/details.aspx?ID=110
I played with the adjustable advance curve with some success.

~WB

Gordon, the weber set-up available through CB employes an equilizer tube between the manifolds similar to what you describe, something that I don't have on the webers I'm using now. Having little experience with this stuff I never gave it a thought but now that you mention it , it makes sense....I think.

Gordon,
I switched over to a Pertronix flamethrower billet dizzy.
That, along with proper jetting on my Webers, eliminated the flat spot.
The Mallory distributors work well, too.

YOUR MAY NEED TO GO LARGER PUMP SQUIRTER'S IN SIDE YOUR CARB TO LOOSE YOUR FLAT SPOT IT'S MOST LIKELY LEAN SWITCHING FROM YOUR IDLE JET'S TO YOUR MAIN JET'S

ROLAND

Roland:

That's a very common misconception, that the accel jets aren't squirting enough juice when you step gently on the accelerator, but I checked all that eons ago and adjusted accordingly - they're actually over-compensating and it still has a flat spot. Long ago I also added a fuel-air mix gauge and that showed the same thing, so then I got the car up on jackstands, got it running at 3 grand in fourth and watched the timing while simulating "driving conditions". Found the same thing that LOTS of others have also found - for my engine, the 009 advance curve sucks, period.

Thanks for the tip, Bill......I'll be in touch for more info.

gn

Gordon,
I have the AJ Sims setup on my TD w/ the Kadrons ( dual 40's )w/ vaccum port and their Vaccum advance dizzy w/ elec. points on my 1641 and since the day I installed them and did some small adjustments I have not touched - 5,000 plus miles. I like it alot ( no flat spots )and am just now getting ready to send off some new Kadrons for my new 2010 stroker for my speedster to them for the vacuum work and have them jet the carbs and adjust all to their dizzy. I was going to open a new thread about the subject this week to see if there was a less expensive route ( 199.00 for their vaccum advanced dizzy w/ electronic points alone ) and see what others have done. A Samba store has a similar dizzy for 139.00 - anyone use this one yet?
I was going to try to vaccum port my own this time and drilled out the bushing but could get no air coming through and called Sims for advise and of course they would not help - just send it in to them - it can't be brain surgery, but they claim it is... who knows.
Any thoughts?
Dale

It is definitely NOT brain surgery, but every day there are fewer people who actually know how a carburetor works (as opposed to fuel injection) so the Kadron folks think they've got you by the shorts. Baloney.

This "Tuning a distributor to a carb" business is simply setting up the right advance curve to take advantage of the flow characteristics of the carburetor (and the engine cam, too, to a lesser degree). They all flow a little differently between idle, the various transition ports and then the main jet and you want to tailor the amount of spark advance seen by the cylinders at each of those port transitions in the carb. That's about all there is to it, and it IS a lot easier if you have a carb flow bench to work with, but it can be done with trial and error if you know what to look for and feel. (It can also be done mathematically, but I don't have the patience for that anymore).

It can be simplified, somewhat, if you have an air/fuel mixture meter on board while testing. What you generally find with a 009 distributor is that it provides a relatively stable full advance coming on more-or-less predictably, but that it often doesn't come on anywhere near soon enough (or stable enough) and it can't compensate for low to moderate speed, full power demands. In other words, stomp it at 3 grand rpm and it doesn't have enough spark advance to properly ignite the incoming charge and it bogs.

Hop on over to the Shop Talk Forums (STF) and see what others have been doing on this (there is a LOT going on) and then begin to formulate an attack plan. You do NOT want to just run an equilizer tube between manifolds and tap off of that if you plan on running a more-or-less stock SVDA disti, but it is possible to find the disti vacuum port on a weber or Dell and "T" those together and run a line to an SVDA with good success, IMHO. I've been reading stuff on the STF and finding that many people have already done all of the legwork on this and can pretty much recommend what you need to do depending on what carbs you're running.

gn

Gordon, music to my ears about the 009 basically not having the correct curve, no matter what you do to it. That's the same conclusion I came to. That's why I went Megajolt, I can do whatever advance Iwant at whatever rpm and/or load I want, with 1/10th degree accuracy for each 360 degree turn of the crank:

http://www.autosportlabs.net/Main_Page

I think a lot of my problem was the 009 wore out over time. Shot!
The engine started pinging more and more under the least load.
With the new dizzy, I've got the advance under control more or less and the pinging is virtually gone. I still get a touch under heavy heat soak conditions but not too much. I still can't run as much advance as you guys can. 25 BTDC is about all I can go.(providing my degree pulley is accurate)

~WB

32.5 degrees max advance, Bill! No pinging ever, unless it idles for like a half hour in 90 F plus weather. It has a lot to do w/heads, CR, cam, lifters, intake, exhaust, basically the whole top end. But it also has to do with the basic inaccuracy of the distributor. Mine was +/- 5 degrees, yes 5, at 3000 rpm. That means my timing varied as much as 10 degrees, which is JUNK and UNACCEPTABLE. One or two, even three I could live with, but 10! No F***in way!

Gord; my SVDA (which I got from Aircooled.net) is only hooked up to the left Dell (the right one doesn't have the vacuum thingie) and it works fine in my car. Something to think about....

Hola, Ricardo!

Remind me again....What are you running for displacement and carb size?

How was Mardi Gras?

gn

I have a 1915 cc with stock cam and 40 by 35.5 valve CB 044 heads. It has 1.25 rockers. My Dells are 40's.

Mardi Gras was the pandemonium it always is; estimated attendance this year was 750,000. I basically run for cover and hide in my apartment; it's funny how some of the locals just take off for that week.

Dean
looking forward, a good running 1600 may soon leave you wanting more POWA.

Previous posts outlined the increasing complexity level just with rebuilding/upgrading/tuning carbs. Bigga carbs need changed intakes need betta exhaust and you're $500 carb upgrade budget is soon over a grand.

If your 1600 is stock and fresh, it a prime candidate for turbo. If you're handy, thats a ballpark figure.

TheSamba has several ongoing turbo discussions.

Dave's right about the turbo; low compression ratio is one of the pre-requisites and a stock 1600 certainly has that but....you need to make sure your bottom end is bulletproof and somehow I think that a totally stock 1600 is not going to be able to handle that for an extended, reliable period of time.