Wideband Results

[MikeyM73]

Hey all,

Just an update on this - I made it to Santa Cruz a few weeks back as Clatter had graciously offered to hang and play VW so we ended up pulling the Pertronix and, as others have said, the quality was not all there. Long story short, we ended up taking it all apart, shaft and all, cleaned and deburred everything that moves, greased it up, and reinstalled. Works MUCH better now and I definitely think the vacuum advance is my issue. My old VA can started moving at 8-9". The can I currently have on starts moving at 2-3". The one Clatter has on a spare dizzy he has moves as soon as you barely suck on the diaphragm nipple. I think that's what I need to fix my issue. The VA can made a drastic improvement along with freeing up a hard moving advance plate. As soon as I can find a suitable diaphragm that starts moving as soon as you look at it, I'll install it into a dizzy that we built from a spare unit he had. I have one VA pod coming in today so we'll see how that goes.

Thanks,
Mikey
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'73 Pop-top Westy, found sitting in a field for 10+ years, cleaned up, rebuilt furniture, reloved. Original 1.7 block/fully polished crank, 93mm 1.8L balanced AA pistons & cylinders, new 1.8L balanced rods, HAM 42/36 heads, Scat C25 cam & lubalobe lifters, Dual HPMX40s, R2C filters w/ Outerwears pre-filters, functioning thermostat & flaps, Pertronix Flamethrower III, 4-1 exhaust w/ Cherry Bomb 2" turbo muffler & OEM heater boxes, averages about 19-22ish on the highway.

[Xevin]

Nice!! Time to update your sig line Hope to see you soon buddy. Let me know if you are on the hunt for any parts.
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Keep on Busin'

[MikeyM73]

Hey Kevin,

Good to hear from you. I do need... A part. I need a vacuum advance pod that moves as soon as you barely suck on the port. There are 2 mounting bracket types that I know of - either the 2 hole or 4 hole; large diaphragm, dual vacuum, etc. I can make any of them work. A friend of mine went to Bugorama last weekend and said he'd look for a few old dizzys so I have to check in with him to see if he had any luck.

Thanks,
Mikey
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'73 Pop-top Westy, found sitting in a field for 10+ years, cleaned up, rebuilt furniture, reloved. Original 1.7 block/fully polished crank, 93mm 1.8L balanced AA pistons & cylinders, new 1.8L balanced rods, HAM 42/36 heads, Scat C25 cam & lubalobe lifters, Dual HPMX40s, R2C filters w/ Outerwears pre-filters, functioning thermostat & flaps, Pertronix Flamethrower III, 4-1 exhaust w/ Cherry Bomb 2" turbo muffler & OEM heater boxes, averages about 19-22ish on the highway.

[Xevin]

Did you say you need a DVDA can?
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Keep on Busin'

[MikeyM73]

I can make any of them work. As long as the pull rod has the hole instead of the ball and the diaphragm starts to move at the slightest, lightest, amount of suckage.
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'73 Pop-top Westy, found sitting in a field for 10+ years, cleaned up, rebuilt furniture, reloved. Original 1.7 block/fully polished crank, 93mm 1.8L balanced AA pistons & cylinders, new 1.8L balanced rods, HAM 42/36 heads, Scat C25 cam & lubalobe lifters, Dual HPMX40s, R2C filters w/ Outerwears pre-filters, functioning thermostat & flaps, Pertronix Flamethrower III, 4-1 exhaust w/ Cherry Bomb 2" turbo muffler & OEM heater boxes, averages about 19-22ish on the highway.

[oprn]

The point that it starts to move is not really as relevant as the pressure it takes to get full motion. You need to have a match between the available maximum carb vacuum at normal cruise speed and the full range of the pot.

I think that is the mistake that a lot of guys make. They hook up a vacuum pot to their carb(s), see that it starts to move in the driveway with a timing light and think "It's working, I'm good." when in actual fact it never ever reaches the proper full stroke on the road.

Another thing you will learn is the vacuum it takes to start the pot moving when it is not attached to the distributor is not the same value it takes installed. Not only is there and increase in drag from the distributor point plate but often the spring in the pot has to be compressed some to install the pot due to the distance between the pin the pot arm hooks up to and the distributor body.

The end result being that, yes it is moving but you are never getting to the full 10 or 11* of additional advance that you need, when you need it.

Personal experiance has taught me that this process of matching the vacuum pot to the carbs is not an easy bolt on and go thing but takes a lot of time and tinkering to get right. I fully understand the "Just bolt on a 009 and go, that's all you need!" mentality. Results are less than satisfactory for sure but it saves a lot of headache trying to get vacuum to work efficiently.
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We had the stone age, the bronze age, the industrial age and now we are in the age of mass deception and mind control for corporate profit. (The mass media age)

[MikeyM73]

Yea... tell me about it . I'm living that now. I'd like to get it as perfect as possible but, now, understand that my valve size to engine size combo might not be ideal for a bus. That said, it's MUCH better than it was before (the hesitation during progression)... like almost gone. I get what you're saying about the engine load,, distributor components affecting vacuum, etc. as opposed to on the bench.

The most I can get out of the ported vacuum ports on my 40s is about 3-4".. tops. With my vacuum gun connected to the vacuum advance can, installed on the dizzy in the bus, it starts to move about 3-4" but I'm still not getting much, added advance from the vacuum advance. Still, after freeing up the mechanicals in the dizzy, it did help and did allow for some pull... I'm just trying to make it better to cover that flat spot.

Is there any way or info on how to match up a vacuum advance can with a specific cam and carbs?

Thanks,
Mikey
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'73 Pop-top Westy, found sitting in a field for 10+ years, cleaned up, rebuilt furniture, reloved. Original 1.7 block/fully polished crank, 93mm 1.8L balanced AA pistons & cylinders, new 1.8L balanced rods, HAM 42/36 heads, Scat C25 cam & lubalobe lifters, Dual HPMX40s, R2C filters w/ Outerwears pre-filters, functioning thermostat & flaps, Pertronix Flamethrower III, 4-1 exhaust w/ Cherry Bomb 2" turbo muffler & OEM heater boxes, averages about 19-22ish on the highway.

[Alstrup]

Anything´s possible, - to a degree. If you really really want to use an analog set up on the ignition side I suggest you use one of the early distributors (VJU4 BR8 I believe. Someone correct me if I´m wrong on the part #) That can be adjusted to respond at very low vacum.
That said, with the options available today, and you want super sensivity on the vacum side, you might wanna go a little more modern and get a programmable unit. As I have mentioned before, the 123 bluetooth is a good middle of the road unit which most can figure out working with. If you want to go detailed there are several fair priced 3D units out there to choose from. Look for units that have at least 10 rows of Map options. Then you can really dial your engine in if you put some effort into it. BUT, it can´t cure a poor set up or a bad combo.
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https://www.thesamba.com/vw/forum/viewtopic.php?t=435993

[Lingwendil]

VJU4BR8 (0 231 115 040 alternative/later part number) is a great choice for the adjustable can- I'm running one on my car now and I'm just at 30MPG HWY with it. It has the same mechanical advance curve as the 019 too so works well, if a little archaic. Works well with the chinese IDF clones on my 1776, was able to dial in the vacuum advance easily.

I still haven't finished my programmable ignition setp with the Daytona TCS-1, and to be honest I'm in no big hurry because the VJU4BR8/040 distributor is so simple and works so well. That, and I don't have any decent distributors on hand I'm willing to modify for locked out advance at the moment.
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73 super beetle thread http://www.thesamba.com/vw/forum/viewtopic.php?t=649622 Back on the Road!

Modify your Kadrons for SVDA http://www.thesamba.com/vw/forum/viewtopic.php?p=8115884#8115884

Cast iron VJU4BR8 SVDA reference thread- https://www.thesamba.com/vw/forum/viewtopic.php?t=...mp;start=0

Need replacement filters for original Kadron aircleaners? WIX #42087 is a perfect fit, as is Napa Gold #2087!

[Clatter]

Since Bosch vacuum cans are getting hard to find in good shape
(And ethanol fuels kill rubber)
Can't help but think there's cans from a different car somewhere...

Mallory can reminds me of something from GM:

Getting OT here, but not really i guess.
Like when Mikey showed up,
Have to dial in your advance before tuning with a wideband!
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Bus Motor Build

What’s That Noise?!?

[Alstrup]

[Dougy Dee]

BUT, at the end of the day it gets to look a little too much Gyro Gearloose for my liking.[/color]
[/quote][/quote]

Most of Gyro Gearloose's elaborate inventions weren't too reliable. Often failed and upset him...

[daos]

delete

[Janne71]

Hi
What jetting did You end up with? Throw my kads away and put idf 40 vent 28 on it. Going to put new linkage because my kads linkage didn’t work out. Tried it and it’s really a different between them. 30 mpg is really good numbers man. Use VJUR4BR8 AND ITS FABULOUS

//Jan

[daos]

would like to get input on my setup.

2007cc stroker with twin Dellorto 40s, mildly ported stock heads, web 163 cam, 1.3 lifters, 9.5 CR, 1 3/8 quiet pack (upgrading soon to 1 1/2) and black box.

currently running with 52 idles only. set LBI, managed to get idle speed at 900rpm and idle AFR at 12.5-13 (around 3 turns out on the mixture screws which is also the recommended base setting for dells). BB timing is set at 10° for 400, 700 and 1000 rpm ranges. rest of the map is standard dual carb provided by CB.

unsure about the vacuum setting, the dells have a vacuum port under each butterfly, these are connected to a small plenum and then to the BB. i tried adjusting using vacuum with the tube from one barrel but the idle speed gets so low the engine just dies and there is still slight vacuum. but it seems happy enough with the above settings.

driving - can get up to around 2800-3000 rpm with gentle acceleration before the idles reach their limit. if i try to put my foot through it at any point after around 1600 rpm it just falls on its face. on light throttle, around 50mph in 4th gear, AFR is around 15 ish. up a hill in 3rd it goes to 14.5-15. do i need to adjust the timing map at this point to get the AFR leaner at light cruise?

i'd like to try 50 idles, need to order those. i have a set of 54 and 56, plan to try the 54s to see what changes.

[Alstrup]

Send a screen shot of your map to my Email.
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https://www.thesamba.com/vw/forum/viewtopic.php?t=435993

[Lingwendil]

[Janne71]

Ok I’ll have to get intakes not leaking to the heads. Chinese sh…

[BIGMIKEY]

Last summer I installed a fresh 1600 with rebuilt 36mm Dellorto DRLA carburetors on straight manifolds in my 1973 Beetle. The carbs initially had what the Superformance book says is the original setup. 30Mm venturis, 122 mains, 60 idles 180 airs, 50 accelerator, 9164.2 emulsions. The engine ran well and drove well and I probably would have left it as it was had I not read the Wide Band tuning thread. Rather than just start out asking questions I decided to try and understand how to tell what jets I needed by reading and searching the thread.

I bought a wide band AFR gage and began tuning the jetting and have reached a point where it seems that I am getting close to my final jetting sizes.

I am joining the thread to see what advice you all can give me.

With the Innovate MTX-L Plus Air Fuel ratio gauge and with help from the Wide band thread I ended up with the following configuration.

1973 beetle 4 speed - 4.125:1 R&P
1600, stock dual port heads with the step
Flat top pistons no dish
.06” deck height
Compression 125 – 135.
stock dished cam, stock lifters
stock oil pump
7:1 compression ratio

Dellorto 36DRLA on straight manifolds. (still no idea who made them)
28mm venturis
1 5/8” velocity stacks with 1.75” clearance to top of air cleaner lid.
118 mains, 52 idles, 180 airs, 9164.2 emulsion, .50 accelerator jet, 150 needle and seats,
floats set 6.5mm/13mm
1 3/8” 4 into 1 exhaust with hideaway muffler
stock diameter aluminum degreed pulley.
SVDA 034 distributor, points, (043 905 205)
Anti pulse valve
Timing 28-30° BTDC hose off, 40° BTDC hose on.
2.5psi fuel pressure

In this configuration the engine runs very well. Responsive to throttle and has lots of power. Really nice to drive. Best of all my gas mileage has improved to a best of 30.2 mpg.

On a flat level road at 3000rpm(55 in 4th) I am seeing 16.4 to 17.1 and pretty stable.
WOT is at 13.1 – 12.5 in 3rd gear uphill pull to 4000rpm.

Appreciate any input.

Mike T

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BIGMIKEY

Deserter Series 1 project.
https://www.thesamba.com/vw/forum/viewtopic.php?t=787047&highlight=

1973 Beetle Driver, Marina Blue.

[oprn]

Looks to me like you have nailed it as far as the carbs go!

The only improvement I would suggest is cut the steps out of the heads, get the deck down to 40 thousands and shoot for between 8.2 and 8.5 C/R. A C/R of 7.0 is pathetic.
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We had the stone age, the bronze age, the industrial age and now we are in the age of mass deception and mind control for corporate profit. (The mass media age)