Home Kadron vacuum port

[vwfan65]

CIP1.com sells both the Bruck and the OEM mex. SVDA. They also give a chart detailing the differences between them as far as degrees of mechanical and vacuum advance (which I posted above albeit not very well). The two are slightly different, but the Bruck works fine for me so far. It looks and feels solid. I have used quite a few Mexican parts, and too many have been crap for me, so paying more for the Mexican product when I am tight on cash wouldn't fly. Had I wanted to spend more, I would probably have just bought A.J. Simm's dizzy and port procedure. Different strokes for different volks.

[vwfan65]

[myolbug]

[Bruce]

[myolbug]

Taken from http://www.oldvolkshome.com/ignition.htm#A6164

[vwfan65]

Sorry for the delay, but I have been busy. As reported in various other threads, the "plug the bottom hole and tap the blind port" procedure does give an adequate vacuum signal to an SVDA. Mine pulls almost no vacuum at idle, then quickly jumps to about 9 inches of vacuum at the first crack of the throttle plate, then quickly tapers down as the throttle is opened wider. This works great with my Bruck SVDA. The SVDA absolutely gives a noticable performance increase as reported everywhere else. I have no concern about fuel vapor, as I pulled the vacuum line from my friends 34 pict-4 right after it ran, and noticed fuel vapor there as well. Not to mention what the pro mechanics at my work told me about the nature of the material used in vacuum diaphragms (fuel resistant, see above).
As it was reported in another thread about the aircooled.net product, this procedure also gives quick and wild pulsing of the vacuum signal as it is only hooked up to two cylinders. My signal did smooth out quite a bit when I hooked up both carbs via a tee connector, but I just did it for a few seconds, and quiclky went back to making the one work by itself as the vacuum signal was off and I had limited time to work. I will continue to test with my vacuum gague and try to get a correct signal using both carbs at the same time. Just for the hell of it, I also took readings from a Kadron that did not have the bottom hole plugged, just the plug tapped. As expected it pulled some vacuum at idle, then dropped, and picked up again as the throttle opened. This is clearly not correct for our application.
I also made sure that the plug and tap procedure has nothing to do with the idling circuit by studying diagrams in my Haynes, and "solex- selection and tuning of the carburetor". I just don't get that whole argument, The passage is connected to NOTHING. The two holes are connected to NOTHING. I tested that passage with a vacuum pump and gague, there is nothing else involved. After the tap and plug alone, my carbs ran exactly the same on my 009. I ran the tapped carb set with the vacuum port plugged on my old 009 before switching to the Bruck. I made no changes in tuning or anything else other than the plug and tap of the carb. I noticed NO difference whatsoever on the engine scope or temp gague pre tap and post tap. The plug and tap alone did not change the way my carbs ran on my engine AT ALL.
It seems to me that nobody has really ever done this "right". Based on my own experience and what others have reported, I personally believe that all available products are just professional rig jobs. I guess that is why an OEM distributor may not work well. If the vacuum signal is a bit off, so too must be the dizzy? It seems that nobody has yet to produce a smooth vacuum signal that matches that of a 34 pict on a stock 1600. If I ever do I will share it. Until then, I am content with my own personal rig job and the money I have saved.
If anyone wants to save about $100, feel confident in doing the "plug and tap" procedure. It is what almost every shops does, and it DOES work fine. If this is not for you then by all means have a pro do this, and rest well knowing that you have purchased a professional product with customer service that will give optimal results. If $100 was not a lot of money to me, I could be without my carbs, and I did'nt enjoy doing this sort of thing myself, I may have payed someone for their procedure, but that is not the case for me.
Just to spite some of the egos around here, I will keep working on getting a stock type vacuum signal from both carbs at the same time on my engine. I am confident it will not be hard to do. I will start playing around with vacuum restrictors and the like. I already have both carbs plug and tapped, but I need to study my buddies stock 1600 34 pict engine some more. I hope my thread has helped a few, everyone else can go jump in the lake. More soon...

[vwfan65]

Well, I have done two things. I ported both carbs. One just has the plug drilled and I have it capped with a vacuum cap, but the other has the tap and bottom hole plugged. It ran fine with just the one tap and plug hooked up like everyone else (except those that sell different procedures) said it would. Only one shop in my area will tap the Kadron, and I found out that they do it this way as well. I did not have time to do a full tune up and thorough road test with gauges as I was doing an engine rebuild as well. I just got everything hooked up, let it idle for a couple minutes and then drove it to my parking spot to finish next weekend. I know that I did this a bit backward, but after reading some of the other posts on the topic, I really want to see what kind of vacuum signal both carbs will give off if they are both tapped with nothing plugged and then run to a T adapter before the SVDA. Anyone else already tried that? I will have to unplug the one carb, but I have both of the ports in place already.
I cannot believe that the passage behind that plug was meant for nothing. It is connected to nothing else at all. I tested it with a vacuum gauge and pump, it goes nowhere but the two holes that exit around the throttle plate. That had to be engineered for some reason. Maybe for another application- but it is a carb after all, not the Winchester House. More results next weekend

[vwfan65]

Another guy told me he had AJ's procedure with a Bruck SVDA and it worked good as well.

[a_67vdub]

FWIW I have AJ's carbs with Johns SVDA and it works like a champ. It might not be perfect, but it's still a lot better than the 009 it replaced.



Steve

[vwfan65]

AJ and John's are different. They both insist on using their dist., and say no other will work because of their custom advance curve. I spoke to AJ on the phone a while back, and he told me that his product gives a very immediate and substancial vacuum advance boost that quickly tapers off as RPM increases. As you can see from my previous post, the OEM distributors are not designed to work that way.
One thing that occurs to me is that it seems to me that both of these guys are just trying to address the terrible flat spot just off idle with Kads and an 009, not give a set of Kads an OEM type of vacuum signal, hence the need for their dist. I am trying to get an OEM type of signal, so I can use an OEM type distributor.

[vwfan65]

Interesting... that is probably why a "special" dist. is needed. I wonder if anyone has tried just drilling and tapping both carbs at the plug without plugging any of the passages? That would involve all 4 cylinders at least. When I get to my car and tools this weekend, I will get into this quite a bit. Here are the vacuum charecteristics for two of the popular OEM replacements from CIP1.com:



VW Mexico Vacuum distributor Bruck Vacuum distributor
ENGINE
RPM Degrees of advance Degrees of advance
800 0 0
1000 0 0
1200 1 1
1400 2 2
1600 5 4
1800 5.5 5
2000 6 6
2200 6.5 6
2400 7 7
2600 7.5 7.5
2800 8 7.5
3000 8.5 8
3200 9 9
3400 9.5 9
3600 10 10
3800 11 11
4000 11.5 11

Vacuum advance Inches of Vacuum Inches of Vacuum
1 Degree 3.5 inches 4 inches
2 Degree 4 inches 5 inches
3 Degree 5 inches 6 inches
4 Degree 6 inches 7 inches
5 Degree 8 inches 8 inches
6 Degree 9 inches

[Matthew]

Check out this thread. Max Welton has some intresting test results on aircooled. net's vacuum port. I wonder if his is different than AJ's port?

http://www.thesamba.com/vw/forum/viewtopic.php?t=127416&highlight=

[vwfan65]

Don't expect anyone who owns a shop to help us by condoning the posting of detailed pictures. Although not illegal in any way, or even all that immoral to me, who would be happy with someone breaking their near monopoly of the procedure? All of the secrecy tells me personally that it is not really very difficult. Ask any body or machine shop how to do one of their procedures and they will gladly tell you in infinate detail how it is done and all of the tools they use just to demonstrate how difficlut it really is (subsequently earning your business). I once asked the owner of my favorite body shop how to color sand because I wanted to try my first two stage paint job myself. He laughed and told me, daring me to try it myself (we are friends). I later wound up paying him over $300 to hand polish my paint job after I botched it.
Anyone can drill out the existing plug on the blind passages, or into the throttle body, but the real trick is getting those passages to send the same vacuum signal on two cylinders that a stock solex sends on all four. Different flow rates, manifold, and choke tube size also affect the whole thing. I don't personally care how I get there, as long as it works and does not afect anything else adversely. Anyone that wants some good info about Solex carbs in general should visit: http://failsure.net/oacdp/pdfs/solex.pdf
This manual should help some of the clueless understand carb operation.

[Matthew]

Someone is going to sue you for displaying pictures of YOUR carbs? I just don't get it. I'm sure there is much more to the procedure than a few lousy pictures is going to unveil. Why should AJ get upset for showing pictures of YOUR carbs? As far as I can see since they belong to you and you can do whatever you please with them. If people realize that there is more to the procedure than they think then it would give AJ more business, not take away from it. Besides, last I heard there was no patent on the Kadron vacuum port process. Even if there was a patent, you are not infringing on anyones rights by displaying a picture of said product. There are plenty of pictures on the internet of patented merchandise.

[71surfbus]

John that`s what I mean, DON`T DO IT!! Just like when I listened to my friend on how to build my motor the Frist time (B.S. before Samba). It was all his fault, he told me what to do!! Or mabe you could just send them a release of Liable, so they can`t come back and sue you

[pribs67]

I have a set of Kadrons I just had AJ's shop do for me that I haven't installed yet. To me it was worth the $40 to not screw up my carbs (since I don't have the proper tooling and experience), and they needed other work anyway. On the other hand, I do see the point about wanting to do-it-yourself and the shipping downtime is pretty lame, especially if your carbs are your only intake system on your only car.

Given that, if AJ will give me permission I will take pictures of the vacuum port on my carbs and post them. This is again only if AJ will allow it.
_________________
Jonathan Pribble

1967 Beetle - Wolfgang Otto
1970 Beetle - Der Haufen

"How you uh, how you comin' on that novel you're working on? Huh?"

[vwfan65]

Thats also great that you want to build your own brick wall. Nothing wrong with that. But, if you get done and find the wall starting to sag or tip over in a few years, I would suggest you find someone other than the bricklayer to give you tips on how to repair it.

Believe me, I understand that. I have mucked up as many things as I have gotten right on the first try. I think I made my favorite body shop rich by fixing my first several paint jobs even though I was being guided by a pro the whole time. (body work is one of the few things I tell people not to try themselves unless they have serious amounts of time, $$$, and patience) Sometimes there is NO substitute for experience. As a cook, I also know that nobody gets a new recipe right on the first try, thats just the nature of the beast.

[a_67vdub]

vwfan65 - I for one don't think you are doing anything wrong by asking questions and doing your own research on the passages in the carb. In fact, this thread has been relatively tame compared to past threads on the subject. The past threads get heated when people expect to get a lesson complete with pictures and a video and a money back guarantee. They often times forget that the people giving advise and information are here because they want to be here, not because they have to.

Thats also great that you want to build your own brick wall. Nothing wrong with that. But, if you get done and find the wall starting to sag or tip over in a few years, I would suggest you find someone other than the bricklayer to give you tips on how to repair it.



Steve

[vwfan65]

I'm still working on it. I had to send some parts for my rebuild back to the shop due to defects, so I have been delayed. My buddy has a 1600 34 pict-3 with a new Bruck SVDA bought from CIP1. The Bruck is marketed as an OEM quality, german manufactured replacement, but the vacuum advance is slightly different from the new OEM Mexican SVDA. CIP1.com gives details on both on their online store.
My friend's car runs great with the Bruck. I'll just keep at it until I get my vacuum signal to match his using a simple vacuum gague. So far I have done the "plug the bottom hole with solder and tap the port" thing. It is completely reversable, so I did not see the harm. I will report back in a week or two. The only thing that occured to me is that now no air can pass through the carb from the bottom hole through the top hole when the throttle plate is closed as it normally would. I do not think relevant amounts of air are involved in that way, but never the less the fact remains and I will keep that in mind. A few more thoughts...
If I need a brick wall, am I obligated to hire a bricklayer?
Is it the bricklayer's right to be the only person who knows how to lay bricks?
Is it wrong for me to try and learn how to lay bricks myself?
Should I feel bad about building my own brick wall because I took business away from a bricklayer?
If someone wants to share the bricklayer's "trade secrets" with me should I cover my ears and run away?

No, no, no, no, and no.
If I am being honest, I would say- Screw the bricklayer, I am building my own damn brick wall.
If the procedure or product is not patented it is fair game. That is the law. I have the right to compete for my own business, and that is what I do every time I choose to do something myself. I am not saying that the bricklayer has to be happy that I am building my own wall, or that he has to help me, but don't anybody piss on me for doing things myself. That IS my right.

[TedzBug]

and personally i like to do things myself also..... The reason i bought a TIG learned how to weld for free from someone who has taken training and worked in welding for years.... And built my own suspension for my rock-crawler jeep a few years ago. When i could have purchase the suspension from a catalog and just installed it.....Did they miss my sale...Probly not.
_________________
'75 Super Beetle
http://www.pbase.com/tedzillich/1975_super_beetle