Hello! Log in or Register   |  Help  |  Donate  |  Buy Shirts  See all banner ads | Advertise on TheSamba.com  
TheSamba.com
 
bigger venturi for 34 pict 3
Page: 1, 2, 3, 4  Next
Forum Index -> Performance/Engines/Transmissions Share: Facebook Twitter
Reply to topic
Print View
Quick sort: Show newest posts on top | Show oldest posts on top View previous topic :: View next topic  
Author Message
joemama
Samba Member


Joined: February 09, 2006
Posts: 915
Location: La Crescenta, California
joemama is offline 

PostPosted: Fri Jan 10, 2020 9:51 am    Post subject: bigger venturi for 34 pict 3 Reply with quote

Wondering if anyone sell one?
Back to top
View user's profile Send private message Gallery Classifieds Feedback
andk5591 Premium Member
Samba Member


Joined: August 29, 2005
Posts: 16205
Location: State College, PA
andk5591 is offline 

PostPosted: Fri Jan 10, 2020 10:35 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Check with John at aircooled.net. I think he was doing something with those
_________________
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...
Back to top
View user's profile Send private message Send e-mail AIM Address Gallery Classifieds Feedback
rayjay
Samba Member


Joined: March 26, 2008
Posts: 574
Location: Buford GA
rayjay is offline 

PostPosted: Fri Jan 10, 2020 11:01 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

I wonder if you could modify the stock one to match these grooved ones ?

https://www.thesamba.com/vw/forum/viewtopic.php?t=...p;start=20
Back to top
View user's profile Send private message Classifieds Feedback
Brian
Samba Moderator


Joined: May 28, 2012
Posts: 8131
Location: Oceanside
Brian is offline 

PostPosted: Fri Jan 10, 2020 3:13 pm    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

34pict3 vent is not a removable item, you'd have to ream it out. I had this done by Tim at Volkzbitz
_________________
Wash your hands

'69 Bug
'68 Baja Truck
'71 Bug
'68 Camper

Only losers litter
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
joemama
Samba Member


Joined: February 09, 2006
Posts: 915
Location: La Crescenta, California
joemama is offline 

PostPosted: Fri Jan 10, 2020 4:49 pm    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Brian. Were you happy with the results? I am thinking of doing it for a mild 1776 with Engle 100, running stock muffler and vaccum advance distributor.
Thanks.
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Brian
Samba Moderator


Joined: May 28, 2012
Posts: 8131
Location: Oceanside
Brian is offline 

PostPosted: Fri Jan 10, 2020 5:20 pm    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

It was on a 2007cc single port, it was pretty cool. Wouldn't do it again unless I had my own dyno and days to spend tuning it properly, doing more head work, more tuning and etc.
_________________
Wash your hands

'69 Bug
'68 Baja Truck
'71 Bug
'68 Camper

Only losers litter
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
busdaddy
Samba Member


Joined: February 12, 2004
Posts: 43422
Location: Surrey B.C. Canada, Land of the giant flying moose!
busdaddy is online now 

PostPosted: Fri Jan 10, 2020 5:34 pm    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

I've had the venturi out, you have to remove that dime sized plug that sometimes falls out of the back of the carb, that's what holds it down IIRC.

https://www.thesamba.com/vw/forum/search.php?searc..._chars=200
_________________
Rust NEVER sleeps and stock never goes out of style.

Wanted, OG paint 1971 Niagara blue decklid.

Stop dead photo links! Post your photos to The Samba Gallery!
Back to top
View user's profile Send private message Gallery Classifieds Feedback
ccowx
Samba Member


Joined: May 15, 2015
Posts: 268
Location: Whitehorse Yukon
ccowx is offline 

PostPosted: Sun Jan 12, 2020 12:57 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

I will be curious to see how this works. I have a very similar engine and carb, but have not been able to fire it up. Mine is an 1835 with an Engle 100 cam, header(with pre-heat), '205AN distributor (recurved) and a 34-3 I have reamed out myself. It actually was not hard to do, it just took a couple of hours of careful work with a dremel tool. If you take out the plug and the butterfly/shaft, it is fairly easy. My venturi is 28mm and I am hopeful that I have the radius' not too far off!

I tried to remove the venturi, but even with the plug out it did not want to come out for me.

Chris
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
FreeBug
Samba Member


Joined: March 12, 2012
Posts: 3379
Location: deepest, darkest Switzerland
FreeBug is offline 

PostPosted: Sun Jan 12, 2020 1:29 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

busdaddy wrote:
I've had the venturi out, you have to remove that dime sized plug that sometimes falls out of the back of the carb, that's what holds it down IIRC.

https://www.thesamba.com/vw/forum/search.php?searc..._chars=200


This. Harder to remove than on a PDSIT, but removable nonetheless
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Alstrup
Samba Member


Joined: July 12, 2007
Posts: 4286
Location: Videbaek Denmark
Alstrup is offline 

PostPosted: Sun Jan 12, 2020 5:32 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Hello.
When the plug and shaft is out it is easy to remove the venturi. Occasionally it is beneficial to het the body a little to loosen it, but normally a gentle tap with a big screwdriver will send it on its way.
I will not say that it is impossible to ream the venturi out with a Dremel, but thge risk is that you move the break point too much. If that happens the signal to the aux venturi gets significantly changed and you can end up with a carb that is difficult to jet.
28-28,5 mm venturi generally works well on engines in the 70 - 85 hp region. Also, with that size the vacum signal is still "trustworthy" At even 29 mm venturi it begins to alter the vacum signal. (It should not have anything to do with each other since the vacum is basically run with/on the idle circuit, but it does.)
29/30 mm venturi is only interesting at at least 1835 cc and 90-110 hp.
2 l plus engines can be run with no venturi, but the jetting becomes rather funky. Also, if you want it to work well you should really use a programmable ignition such as the CB Black box. With this you can iron some of the issues out and make it work well. - It can be done with a regular 009, but it is very difficult. With a programmable it is so much easier.

As a rule of thumb sgl port engines want a 10% smaller square venturi for the same displacement. If you keep the factory steel intake there is no idea in going larger than 28 mm (on a street engine) because the manifold will not be able to flow more. In fact the difference between a 26 and a 28 mm venturi is minor. Converting to a better manifold and everything changes.
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
joemama
Samba Member


Joined: February 09, 2006
Posts: 915
Location: La Crescenta, California
joemama is offline 

PostPosted: Mon Jan 13, 2020 12:24 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Here is my carburetor
Image may have been reduced in size. Click image to view fullscreen.

removed spring
Image may have been reduced in size. Click image to view fullscreen.

removed screws
Image may have been reduced in size. Click image to view fullscreen.

you have to use a screwdriver that fits well, the screws are tough to remove because they are peened over to keep from backing out
Image may have been reduced in size. Click image to view fullscreen.

butterfly removed
Image may have been reduced in size. Click image to view fullscreen.

removed linkage from throttle shaft
Image may have been reduced in size. Click image to view fullscreen.

removed electric idle solenoid
Image may have been reduced in size. Click image to view fullscreen.

pulled throttle shaft out
Image may have been reduced in size. Click image to view fullscreen.

you can see the venturi, as well as the plug that keeps it in
Image may have been reduced in size. Click image to view fullscreen.

drilled a small hole thru the plug and used a slide hammer to pull the plug free. I can reuse the plug with some jb weld to plug the hole I drilled and to hold the plug in
Image may have been reduced in size. Click image to view fullscreen.

removed the top of the carburetor, you can see the venturi
Image may have been reduced in size. Click image to view fullscreen.

used a wood dowell and hammer, tapped different spots around the venturi, and drove it out
Image may have been reduced in size. Click image to view fullscreen.

looking at the venturi, looks like I need to find someone with a lathe, and enlarge this area by 2mm (is that correct, Allstrup?)
Image may have been reduced in size. Click image to view fullscreen.

Also, here is the manifold I plan to use, its from a '71, I cleared the heat risers with a drill motor and a wire cable
Image may have been reduced in size. Click image to view fullscreen.

measuring across the intake it is 1" 4/10, which is about 36mm. Im hoping that is large enough to handle the 28mm venturi
Image may have been reduced in size. Click image to view fullscreen.

If I can get verification that this is the area I need to enlarge, and doing just that is what I need to do, I will proceed.
Thanks.
Image may have been reduced in size. Click image to view fullscreen.


Image may have been reduced in size. Click image to view fullscreen.
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Alstrup
Samba Member


Joined: July 12, 2007
Posts: 4286
Location: Videbaek Denmark
Alstrup is offline 

PostPosted: Mon Jan 13, 2020 4:09 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Yes, but the best way is to continue the taper to the bottom or at least close to.
There is no need to drill the plug. Just take a big screwdriver and give it a couple of punches from the inside and it will come out.
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
Rome
Samba Member


Joined: June 02, 2004
Posts: 6223
Location: Pearl River, NY
Rome is offline 

PostPosted: Mon Jan 13, 2020 4:52 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Thanks for the detailed procedure, joemama.
Back to top
View user's profile Send private message Gallery Classifieds Feedback
gt1953
Samba Member


Joined: May 08, 2002
Posts: 12753
Location: White Mountains Arizona
gt1953 is offline 

PostPosted: Mon Jan 13, 2020 6:55 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

I have always wondered why Solex did not make a larger single center mount carb. Like say a 38 Pict.
_________________
Volkswagen: We tune what we drive.
Numbers Matching VW's are getting harder to find. Source out the most Stock vehicle and keep that way. You will be glad you did.
68 type 1
72 type 1
73 type 1
72 Squareback
({59 Euro bug, 62, 63, 67, 69 type ones 68 & 69 type two, 68 Ghia all sold})
Back to top
View user's profile Send private message Gallery Classifieds Feedback
rayjay
Samba Member


Joined: March 26, 2008
Posts: 574
Location: Buford GA
rayjay is offline 

PostPosted: Mon Jan 13, 2020 7:11 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

gt1953 wrote:
I have always wondered why Solex did not make a larger single center mount carb. Like say a 38 Pict.


VW was probably the leader of the pack when it came to FI on production cars so would have no need to spend money on further carb development.
Back to top
View user's profile Send private message Classifieds Feedback
joemama
Samba Member


Joined: February 09, 2006
Posts: 915
Location: La Crescenta, California
joemama is offline 

PostPosted: Mon Jan 13, 2020 8:07 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

a few years back there was a kit on the market for a single Kadron. I always thought that would have worked well.
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Alstrup
Samba Member


Joined: July 12, 2007
Posts: 4286
Location: Videbaek Denmark
Alstrup is offline 

PostPosted: Mon Jan 13, 2020 11:32 am    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

joemama wrote:
a few years back there was a kit on the market for a single Kadron. I always thought that would have worked well.

It does, and it donīt.
In warm and dry climates like Southern CA,Arizona, NM, Texas and similar it works quite well. In slighty more chilly climates like here for instance, the warm up period is just downright impossible. Makes the engine jerk and buck until some heat comes into the manifold. Next it was soon found out that it was not the carb that was the problem, its the manifold and end pieces. A 34 mmn Solex Pict3 or 4, can supply 100 hp (street) with no other mods than the venturi change and a rejet, and a proper aircleaner. (Going extreme it will handle up to about 120 hp.)
A modified 34 Solex with a 37 mm butterfly and a custum venturi along with a modified CB/Empi center section and modified end castings (or a set of Wensings new larger I.D. castings) will support 120 hp and up to about 130 in the extreme.
With this solution "everything still fits" and you do not need to fight with a flimsy linkage and what not as with the Kadron conversion. Thatīs why I for one abandonned the centermount Kadron solution
Back to top
View user's profile Send private message Send e-mail Gallery Classifieds Feedback
joemama
Samba Member


Joined: February 09, 2006
Posts: 915
Location: La Crescenta, California
joemama is offline 

PostPosted: Mon Jan 13, 2020 1:51 pm    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Alstrup, sorry if I am being dense, but I want to be sure
Image may have been reduced in size. Click image to view fullscreen.

Are you saying That I need to open up both these areas, the "belt" at the narrow part of the venturi, and also the slightly beveled area from there down to the end of the venturi?
Thanks.
Back to top
View user's profile Send private message Gallery Classifieds Feedback
rayjay
Samba Member


Joined: March 26, 2008
Posts: 574
Location: Buford GA
rayjay is offline 

PostPosted: Mon Jan 13, 2020 3:44 pm    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Imagine that the inside of the venturi is the top surface of an airplane wing. An airfoil in other words. You want a smooth radius so that the air stays attached. So really you want to blend both the top transition to the new larger bore and the bottom. Really, there should be no parallel portion of the venturi.
Back to top
View user's profile Send private message Classifieds Feedback
joemama
Samba Member


Joined: February 09, 2006
Posts: 915
Location: La Crescenta, California
joemama is offline 

PostPosted: Mon Jan 13, 2020 4:18 pm    Post subject: Re: bigger venturi for 34 pict 3 Reply with quote

Currently the part where the pen is pointing to, is practically a flat belt, with a sharply defined top and bottom edge. So sounds like along with widening the hole to 28mm, those sharp edges should be smoothed out and blended in.
Thanks.
Back to top
View user's profile Send private message Gallery Classifieds Feedback
Display posts from previous:   
Reply to topic    Forum Index -> Performance/Engines/Transmissions All times are Mountain Standard Time/Pacific Daylight Savings Time
Page: 1, 2, 3, 4  Next
Page 1 of 4

 
Jump to:  
You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot vote in polls in this forum

About | Help! | Advertise | Donate | Premium Membership | Privacy/Terms of Use | Contact Us | Site Map
Copyright © 1996-2020, Everett Barnes. All Rights Reserved.
Not affiliated with or sponsored by Volkswagen of America | Forum powered by phpBB