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brewtech
Samba Member
Joined: April 30, 2007
Posts: 105
Location: Los Angeles
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 Posted: Sun Jan 15, 2012 4:38 pm Post subject: Dual Kadrons are running great but I need some tuning help |
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Hi guys, I just put together a dual kad setup from the kaddie shack, and I'm experiencing a bit of a flat spot/ power drop when I accelarate. If I drive it on the streets without asking for power i can actually drive ok. But lets say I'm already on the freeway in 4th, if I accelarate i can feel a rough spot and the only way to overcome it is to floor the pedal which then smooths out the rev. Do you guys think, perhaps my accelator pumps are not max squirting while I rev up? Or perhaps my jetting ain't right. I'm kinda lost right now. Exhaust is a bit smelly, but not the crying type. I could sure use some help.
Specs:
I think I have 1600dp
sync'd dual kadrons
Pertronix Flamethrower SVDA dizzy with electonic ignition
Valves adjusted
New plugs/cap/rotor
Fuel Press. Reg.
30 deg timing at full throttle |
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[email protected]
Samba Member
Joined: August 03, 2002
Posts: 12785
Location: Salt Lake City, Utah
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| Posted: Sun Jan 15, 2012 4:57 pm Post subject: Re: Dual Kadrons are running great but I need some tuning he |
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which fuel pressure regulator do you have?
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Altema
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Joined: June 20, 2010
Posts: 2904
Location: Lower Michigan
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| Posted: Sun Jan 15, 2012 4:58 pm Post subject: |
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Just a few questions:
When you say the exhaust is smelly, do you mean the sooty smelly kind and black soot inside the tailpipes? If so, they are jetted too rich and the accel pump will cause it to bog. Best way to check jetting is to pull the spark plugs (not when engine is hot, of course) and see if they are an even tan color. Dark brown or black means your jetting is too rich, white means too lean.
30 degrees total is fine, but that's with the vacuum advance line disconnected, right? If the vacuum line was on when max timing is set, then you will have mechanical plus vacuum advance, and that vacuum advance will go away when you accelerate.
Jetting seems like the primary issue, but make sure there are no timing issues to complicate matters.
Paul |
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DarthWeber
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Joined: November 24, 2007
Posts: 7543
Location: Whittier,CA
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| Posted: Sun Jan 15, 2012 5:04 pm Post subject: |
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1600 huh? Are you sure there isn't a 2276 hiding under that tin?? 
Have you visually checked (engine off) the accel pump tubes to make sure they are both squirting equal amounts? Make sure the ends of the tubes are not down in the venturis or gas will siphon out and you won't get a full shot. Before you installed the Kads did you remove the accel pump covers and carb tops to check for dirt? Yes I know Jeff just rebuilt them and he does stellar work....but did you check?
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| Mitey62 wrote: |
| Swapped the Compufire for a Bosch blue and some points I had sitting around, started 1st crank. Took her out for a drive, pulls harder, more RPM, and runs smoother. I think I'll be sticking with points from now on. |
| RockCrusher wrote: |
JB weld the case halves....that'll keep the fretting to a minimum.  |
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brewtech
Samba Member
Joined: April 30, 2007
Posts: 105
Location: Los Angeles
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| Posted: Mon Jan 16, 2012 3:23 pm Post subject: |
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| Thanks for the replies. I was busy effing around with the carbs and fuel reg. I think I got it pretty close to smooth revs all the way through, and the rough spot is minimal. I did time it with the dizzy Vac line disconnected. Am I knit picking or am I right for wanting seamless revs? Anyway, I did notice that the accelarator pump on the left hand side carb has almost no resistance when I turn it in. The right hand side has a nice resistance to it and by comparison I'd have to say that either the arm has come off or its not working properly. My fuel reg is a cheapy one that I have to replace with a nice Holley model. My smelly exhaust has also calmed down alot ever since I made the accelarator pump adjustment. Its now a nice carburated AC smell. It hauls on the freeway with almost no stumble, still I think it can improve. I really wish there was a way to know size motor I really have without pulling a head. I do have a lope in the exhaust while idling, could be cammed diff from stock. One more question, Is it okay to have only one carb hooked up to the dizzy, or should I Tee it to both carbs? |
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brewtech
Samba Member
Joined: April 30, 2007
Posts: 105
Location: Los Angeles
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| Posted: Wed Jan 18, 2012 12:30 am Post subject: |
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| DarthWeber wrote: |
1600 huh? Are you sure there isn't a 2276 hiding under that tin??
Have you visually checked (engine off) the accel pump tubes to make sure they are both squirting equal amounts? Make sure the ends of the tubes are not down in the venturis or gas will siphon out and you won't get a full shot. Before you installed the Kads did you remove the accel pump covers and carb tops to check for dirt? Yes I know Jeff just rebuilt them and he does stellar work....but did you check? |
What do mean by the tubes not being down in the Venturis? I'm becoming more and more acquainted with my carbs, but I'm still experiencing that loss of power upon accelaration. I did not check anything. I just bolted them on and began to try to smoothen it out. I figured I wouldve had this figured out by now. I will try more Accelator pump adjustments just to see if I get somewhere. |
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gearhead91
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Joined: May 02, 2010
Posts: 46
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| Posted: Wed Jan 18, 2012 10:18 am Post subject: |
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| the accel. pump tubes are the little brass looking ones just above the venturi. if you look down the throat of the carb from the top you will see them, there is only one in each carb. |
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andk5591
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Joined: August 29, 2005
Posts: 16757
Location: State College, PA
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| Posted: Wed Jan 18, 2012 3:42 pm Post subject: |
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.oops
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
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Last edited by andk5591 on Wed Jan 18, 2012 3:44 pm; edited 1 time in total |
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andk5591
Samba Member
Joined: August 29, 2005
Posts: 16757
Location: State College, PA
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| Posted: Wed Jan 18, 2012 3:43 pm Post subject: |
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how are you adjusting the accel pumps? And make sure they arent dribbling when its running. Should see a nice stream from both when you blip the throttle. I would have thought that they would have been set correctly from Kaddie Shack........
And I also STRONGLY suggest that you properly synch your carbs.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them... |
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borninabus
Samba R&D Dept.
Joined: May 18, 2006
Posts: 4536
Location: Arizona Highways
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| Posted: Wed Jan 18, 2012 4:31 pm Post subject: |
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| brewtech wrote: |
| Is it okay to have only one carb hooked up to the dizzy, or should I Tee it to both carbs? |
you should T it to both carbs.
that could be your whole problem.
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brewtech
Samba Member
Joined: April 30, 2007
Posts: 105
Location: Los Angeles
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| Posted: Wed Jan 18, 2012 6:32 pm Post subject: |
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| gearhead91 wrote: |
| the accel. pump tubes are the little brass looking ones just above the venturi. if you look down the throat of the carb from the top you will see them, there is only one in each carb. |
Gotcha, I was looking in there and saw the tubes. The thing that's confusing me is, MAKE SURE THEY ARE NOT DOWN IN THE VENTURI. Did he mean to make sure mine haven't dettached from the carb and actually fallen into the venturi or did he mean to make sure they are not pointing down into the venturi. Mine are attached and pointing downward into the venturi. Straight down. I'll check soon if they are dripping or not. I'm adjusting the accelarator pumps by turning in the nut at the arm. I did lean it out a bit today, and noticed and improvement, but of course this happened 5 minutes before I arrived to work. Gonna see if anything has changed once I drive home tonight. I will make sure to "T" the vaccum line. Thanks. |
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Altema
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Joined: June 20, 2010
Posts: 2904
Location: Lower Michigan
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| Posted: Thu Jan 19, 2012 4:09 am Post subject: |
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| brewtech wrote: |
| gearhead91 wrote: |
| the accel. pump tubes are the little brass looking ones just above the venturi. if you look down the throat of the carb from the top you will see them, there is only one in each carb. |
Gotcha, I was looking in there and saw the tubes. The thing that's confusing me is, MAKE SURE THEY ARE NOT DOWN IN THE VENTURI. Did he mean to make sure mine haven't dettached from the carb and actually fallen into the venturi or did he mean to make sure they are not pointing down into the venturi. Mine are attached and pointing downward into the venturi. Straight down. I'll check soon if they are dripping or not. I'm adjusting the accelarator pumps by turning in the nut at the arm. I did lean it out a bit today, and noticed and improvement, but of course this happened 5 minutes before I arrived to work. Gonna see if anything has changed once I drive home tonight. I will make sure to "T" the vaccum line. Thanks. |
By "down in the venturi", he means to make sure the tip is above where the venturi narrows because there is suction at this point which can draw fuel out of the accelerator nozzle. The nozzle should be pointed down, preferably so it squirts at the edge of the throttle plate where sits when closed. The goal is to get the shot in the opening when the throttle first tips open, rather than run down the side of the carb or splash onto the throttle plate.
Paul |
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andk5591
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Joined: August 29, 2005
Posts: 16757
Location: State College, PA
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| Posted: Thu Jan 19, 2012 4:58 am Post subject: |
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Kaddie Shack should be aware of the accel pump siphon issues - But as mentioned - you should not see any dripping or flow from them when the car is running or when its at a mid or higher throttle position other than when you first hit the throttle.
As far as vac line to one or more carbs - I have dual kads/SVDA on 3 cars and only run a single line. I had done some testing a couple years and found no need to run a line to both.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them... |
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brewtech
Samba Member
Joined: April 30, 2007
Posts: 105
Location: Los Angeles
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| Posted: Thu Jan 19, 2012 2:50 pm Post subject: |
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| Okay Thanks! I'll look again. I'm thinking I'm not Sync'd properly. I decided to lean the carbs out a bit via the Mixture Screw. The idle improved and I noticed more pep, The exhaust is still a bit smelly, since a motorist was kind enough to let me know by waving his floppy hand in front of his face. I'm thinking it's too rich, what's the best way to get a good fuel mixture? I am a newb to the dual carb thing as if you couldnt already tell. |
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andk5591
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Joined: August 29, 2005
Posts: 16757
Location: State College, PA
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| Posted: Thu Jan 19, 2012 4:12 pm Post subject: |
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#1 Are you running a balance tube. Not real important - some do - some don't - I don't. Personal opinion is if they are set up right, you don't need it - but that is my opinion.
#2 What linkage are you using? Personal preference is Scat, but some folks like Kad or others. I like how well I can adjust mine.
#3 to set idle mix - download the setup procdure from here http://kaddieshack.com/, There is a procedure also on Lowbugget.com thats pretty much the same.
#4 Kaddie Shack also has a synch procedure on the download, but I dont agree with it myself. I have had them come from a shop (not Kaddie Shack) pretty close and pretty far off. I use this method - http://www.thesamba.com/vw/forum/viewtopic.php?t=2...p;start=20
I think that once you get through this you should be pretty good. I would assume that the carbs were jetted for your application and should be pretty close. But it's nice to know what they are anyway.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them... |
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brewtech
Samba Member
Joined: April 30, 2007
Posts: 105
Location: Los Angeles
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| Posted: Thu Jan 19, 2012 7:43 pm Post subject: |
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| andk5591 wrote: |
#1 Are you running a balance tube. Not real important - some do - some don't - I don't. Personal opinion is if they are set up right, you don't need it - but that is my opinion.
#2 What linkage are you using? Personal preference is Scat, but some folks like Kad or others. I like how well I can adjust mine.
#3 to set idle mix - download the setup procdure from here http://kaddieshack.com/, There is a procedure also on Lowbugget.com thats pretty much the same.
#4 Kaddie Shack also has a synch procedure on the download, but I dont agree with it myself. I have had them come from a shop (not Kaddie Shack) pretty close and pretty far off. I use this method - http://www.thesamba.com/vw/forum/viewtopic.php?t=2...p;start=20
I think that once you get through this you should be pretty good. I would assume that the carbs were jetted for your application and should be pretty close. But it's nice to know what they are anyway. |
#1 I do have a balance tube. I'll see about plugging them somehow.
I did tell him I have a 1600dp. If I possibly have a 1500cc or 1641cc or anything else I suppose that swapping jets would be in order. Thanks for the link. |
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andk5591
Samba Member
Joined: August 29, 2005
Posts: 16757
Location: State College, PA
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| Posted: Fri Jan 20, 2012 5:40 am Post subject: |
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Not telling you to bag the balance tube. Just that I found I didnt need it - but most folks run with it.
As far as jetting - I have the luxury of tuning on a chassis dyno and/or using an Air/fuel meter to set my jetting. Theres a whole process for reading plugs or using a meter to properly jet. In general, VW people tend to run rich. Not the most efficient way to go, but it hides a lot of problems LOL. The first thing for you though is to get what you have set up properly, then start messing with jets if you need to.
_________________
D-Dubya Manx clone - 63 Short pan,1914.
Rosie 65 bug - My mostly stock daily driver.
Woodie 69 VW woodie (Hot VWs 7/12).
"John's car" 64 VW woodie - The first ever
Maxine 61 Cal-look bug - Cindy's daily driver.
Max - 73 standard Beetle hearse project - For sale
66 bug project - Real patina & Suby conversion
There's more, but not keeping them... |
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