Home  |  Forums  |  914 Info  |  Blogs
 
914World.com - The fastest growing online 914 community!
 
Porsche, and the Porsche crest are registered trademarks of Dr. Ing. h.c. F. Porsche AG. This site is not affiliated with Porsche in any way.
Its only purpose is to provide an online forum for car enthusiasts. All other trademarks are property of their respective owners.
 

Welcome Guest ( Log In | Register )

2 Pages V  1 2 >  
 Reply to this topicStart new topic
> How to make your CB carb linkage NOT SUCK!
Aaron Cox
post Jan 18 2009, 07:15 PM
Post #1


Professional Lawn Dart
***************

Group: Retired Admin
Posts: 24,541
Joined: 1-February 03
From: Corona, CA
Member No.: 219
Region Association: Southern California
Ok, I have tried lots of Carb Linkages over the years, and CB performance tends to be revered near the top end with regards to value and performance. There are a few other linkages out there that I like also...

So fast forward 5yrs, and the CB performance linkage has accrued some sucky slop from years of ball in hole wearing. Slop = bad, causing the carbs to not be synched during mid throttle....

Mind you this is the second or third crossbar replacement... even with grease, the hole gets ovaled and sloppy.

So, how do we fix this? How can we improve upon their design, BUT not go purchase ANOTHER linkage?

Well, simple my friends. A little machining, and parts selection and bobs your uncle!


Step 1, Purchase spare set of CB linkage base plates. Proceed to lop off the uprights near flush with the ridge for the air cleaner.
Attached Image
Attached Image

Step 2: Bring beer to a buddy, and he will let you use his mill. Or will even mill things for you (IMG:style_emoticons/default/smile.gif)

Attached Image

Step 3: Order a bunch of parts from mcmaster.com, Heim Joints, Shoulder Bolts, and Springs (IMG:style_emoticons/default/smile.gif)... Followed by - Find out that mcmaster carr will send you homo pinkish red heim joints and laugh at yourself.

Step 4: Drill and Tap Base plates for heim Joints

Attached Image
Attached Image
Attached Image

Step 4: Measure 3x, and cut your new extra long cross bar to length, drill and tap ends to fit the shoulder bolts.

Attached Image

Step 5: Install stainless springs, Stainless Shoulder bolts, and use blue loctite on all threads.


Attached Image

Step 6: Install onto car, note what a great success it is, and drink copious amounts of beer to give yourself a pat on the back.

Attached Image


The setup works great.
It gets rid of the big extension lever on the offset version of the CB plates.... Gets rid of the worn ball and socket pivot, And self centers like the original linkage did.

Hindsight, I would order bearings instead of heim joints next time, and possibly order slightly stiffer springs, or possibly add tension springs on the other side of the heims to increase centering ability.

Enjoy (IMG:style_emoticons/default/smile.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
So.Cal.914
post Jan 18 2009, 07:32 PM
Post #2


"...And it has a front trunk too."
*****

Group: Members
Posts: 6,588
Joined: 15-February 04
From: Low Desert, CA./ Hills of N.J.
Member No.: 1,658
Region Association: None
(IMG:style_emoticons/default/smilie_pokal.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Aaron Cox
post Jan 18 2009, 07:33 PM
Post #3


Professional Lawn Dart
***************

Group: Retired Admin
Posts: 24,541
Joined: 1-February 03
From: Corona, CA
Member No.: 219
Region Association: Southern California
Additional:

The goal was to mimic the TRIAD design, but improve on it also. Ideally, you use the centering spring technology used on CB's design, but improve upon it with heim joints like Triad uses.

A marriage of 2 good systems = a better system for less money.
245 for a linkage is too much.... The way i did it, can be made for ~ 60 bucks or so.


Triad Linkage
(IMG:http://www.triadwestperformance.com/Images/linkage-large.JPG)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
r_towle
post Jan 18 2009, 07:35 PM
Post #4


Custom Member
***************

Group: Members
Posts: 24,705
Joined: 9-January 03
From: Taxachusetts
Member No.: 124
Region Association: North East States
Nice job. I had a setup like that on a race car...it was an old school linkage...
The one thing to watch (at least on a hypo motor) was that the motor itself, therefore the position of the carbs, expands up to a half inch.

Rich
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
KaptKaos
post Jan 18 2009, 07:40 PM
Post #5


Family
****

Group: Members
Posts: 4,009
Joined: 23-April 03
From: Near Wausau
Member No.: 607
Region Association: Upper MidWest
Great thread! Who wrote it? :ducks:
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Aaron Cox
post Jan 18 2009, 07:40 PM
Post #6


Professional Lawn Dart
***************

Group: Retired Admin
Posts: 24,541
Joined: 1-February 03
From: Corona, CA
Member No.: 219
Region Association: Southern California
QUOTE(r_towle @ Jan 18 2009, 05:35 PM) *

Nice job. I had a setup like that on a race car...it was an old school linkage...
The one thing to watch (at least on a hypo motor) was that the motor itself, therefore the position of the carbs, expands up to a half inch.

Rich


Good point-
Thats what the springs are there for. I designed upwards of 3/8" expansion into the bar. As the motor grows, the spring force lessens and the bar still stays centered (IMG:style_emoticons/default/smile.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
r_towle
post Jan 18 2009, 07:56 PM
Post #7


Custom Member
***************

Group: Members
Posts: 24,705
Joined: 9-January 03
From: Taxachusetts
Member No.: 124
Region Association: North East States
Welcome back from your self imposed exodus.
Are you finally and Engineer?

Rich
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
scotty b
post Jan 18 2009, 08:30 PM
Post #8


rust free you say ?
***************

Group: Members
Posts: 16,375
Joined: 7-January 05
From: richmond, Va.
Member No.: 3,419
Region Association: None
HIGH FIVE


Attached image(s)
Attached Image
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
FourBlades
post Jan 18 2009, 08:56 PM
Post #9


From Wreck to Rockin
****

Group: Members
Posts: 2,056
Joined: 3-December 07
From: Brevard, FL
Member No.: 8,414
Region Association: South East States

Classic thread???? (IMG:style_emoticons/default/piratenanner.gif) (IMG:style_emoticons/default/smilie_pokal.gif) (IMG:style_emoticons/default/piratenanner.gif)

John
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Jake Raby
post Jan 18 2009, 09:05 PM
Post #10


Engine Surgeon
*****

Group: Members
Posts: 9,398
Joined: 31-August 03
From: Lost
Member No.: 1,095
Region Association: South East States
Cool! One of the things on my task list has been to make a production unit "update kit" to do this with the CB linkage easily. It does make a world of difference.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Aaron Cox
post Jan 18 2009, 10:25 PM
Post #11


Professional Lawn Dart
***************

Group: Retired Admin
Posts: 24,541
Joined: 1-February 03
From: Corona, CA
Member No.: 219
Region Association: Southern California
All you need is a few poor college kids who like beer to machine kits for you (IMG:style_emoticons/default/laugh.gif) the hardest part of mass producing a kit would be the custom bar lengths....

Only took a few hours start to finish
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
So.Cal.914
post Jan 18 2009, 10:56 PM
Post #12


"...And it has a front trunk too."
*****

Group: Members
Posts: 6,588
Joined: 15-February 04
From: Low Desert, CA./ Hills of N.J.
Member No.: 1,658
Region Association: None
I am going to make one. (IMG:style_emoticons/default/smile.gif) Very cool idea.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
craig downs
post Jan 18 2009, 11:14 PM
Post #13


Senior Member
***

Group: Members
Posts: 769
Joined: 25-November 05
From: mira loma ca.
Member No.: 5,189
Region Association: Southern California
Awesome
I miss your project threads, they are always fun to follow along. I hope you have more up your sleeve.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
'73-914kid
post Jan 18 2009, 11:31 PM
Post #14


Senior Member
***

Group: Members
Posts: 1,473
Joined: 1-November 08
From: Vista, CA
Member No.: 9,714
Region Association: Southern California
Hmmm....I just bought a bought a complete CB set.
Brand new, and after daily driving use, how long is the linkage going to last?
This would be any easy thing for me to make, but I would like to find out how long it will be before I get the fitting ovalling out.

But first, I'll need to get my engine so, but everything actually seems pretty strong and tightly clearanced, so I'm not sure what I'll do..... (IMG:style_emoticons/default/unsure.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
Aaron Cox
post Jan 19 2009, 01:02 AM
Post #15


Professional Lawn Dart
***************

Group: Retired Admin
Posts: 24,541
Joined: 1-February 03
From: Corona, CA
Member No.: 219
Region Association: Southern California
QUOTE('73-914kid @ Jan 18 2009, 09:31 PM) *

Hmmm....I just bought a bought a complete CB set.
Brand new, and after daily driving use, how long is the linkage going to last?
This would be any easy thing for me to make, but I would like to find out how long it will be before I get the fitting ovalling out.

But first, I'll need to get my engine so, but everything actually seems pretty strong and tightly clearanced, so I'm not sure what I'll do..... (IMG:style_emoticons/default/unsure.gif)


You'll notice some slop after a year or more.....

You could always just replace the bar and balls when it happens....


BTW - why does CB performace REAM you on shipping? 12 bucks to ship a cross bar.... and they dont tell you what it costs up front.... (IMG:style_emoticons/default/blink.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
PeeGreen 914
post Jan 19 2009, 01:07 AM
Post #16


Just when you think you're done...wait, there is more..lol
**********

Group: Members
Posts: 10,219
Joined: 21-September 06
From: Seattle, WA... actually Everett
Member No.: 6,884
Region Association: Pacific Northwest
Nice work Aaron (IMG:style_emoticons/default/beerchug.gif) It's always fun making things (IMG:style_emoticons/default/piratenanner.gif)
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
ConeDodger
post Jan 19 2009, 01:10 AM
Post #17


Apex killer!
***************

Group: Members
Posts: 24,028
Joined: 31-December 04
From: Tahoe Area
Member No.: 3,380
Region Association: Northern California
Great thread but it looks like SirAndy took that second pic with his old camera! (IMG:style_emoticons/default/shades.gif)
User is online!Profile CardPM
Go to the top of the page
+Quote Post
ottox914
post Jan 19 2009, 07:19 AM
Post #18


The glory that once was.
***

Group: Members
Posts: 1,302
Joined: 15-December 03
From: Mahtomedi, MN
Member No.: 1,438
Region Association: Upper MidWest
QUOTE(ConeDodger @ Jan 18 2009, 11:10 PM) *

Great thread but it looks like SirAndy took that second pic with his old camera! (IMG:style_emoticons/default/shades.gif)


Dd you read step 2 carefully- bring beer to a buddy. It doesn't mention who was to consume the beer. Shame to waste it on the photographer!
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
biosurfer1
post Jan 19 2009, 11:33 AM
Post #19


Teener fo Life!
****

Group: Members
Posts: 3,020
Joined: 3-August 03
From: Roseville, CA
Member No.: 977
Region Association: Northern California
QUOTE(Aaron Cox @ Jan 18 2009, 11:02 PM) *


BTW - why does CB performace REAM you on shipping? 12 bucks to ship a cross bar.... and they dont tell you what it costs up front.... (IMG:style_emoticons/default/blink.gif)


No kidding Aaron...I bought my fuel pump for them and they charged $35 shipping for a $50 pump. When I called to ask "WTF" she said they made a mistake and she would credit the difference back to me. My mistake was I didn't ask what the credit would be....it was $17 so shipping was still $18 for an item that would have EASILY fit in a $5 flat rate box from USPS.

I hate when companies do that!
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
rhodyguy
post Jan 20 2009, 10:11 AM
Post #20


Chimp Sanctuary NW. Check it out.
***************

Group: Members
Posts: 22,240
Joined: 2-March 03
From: Orion's Bell. The BELL!
Member No.: 378
Region Association: Galt's Gulch
springs allowing for side loading suck. much like the stock cb. next time drill, tap and the bar ends using bolts with jam nuts to keep the bar where you want it when the engine is heated up. just like a triad. so...orginal linkage cost, make a throttle cable holder(we've been down this path), eventually have to endure a shitty carb snapping and poping engine, $60+ on improvements, beer, for those of us who are unable to impose upon a friend add what ever the market will bear for machining and you'll almost have a triad. mine is powder coated your's isn't. hi aaron.
User is offlineProfile CardPM
Go to the top of the page
+Quote Post
« Next Oldest · 914World Garage · Next Newest »
 

2 Pages V  1 2 >
Reply to this topicStart new topic
2 User(s) are reading this topic (2 Guests and 0 Anonymous Users)
0 Members:

 

Display Mode: Standard · Switch to: Linear+ · Switch to: Outline

Track this topic · Email this topic · Print this topic · Subscribe to this forum

- Lo-Fi Version Time is now: 9th May 2025 - 09:57 AM
Invision Power Board v9.1.4 © 2025  IPS, Inc.
All rights reserved 914World.com © since 2002
914World.com is the fastest growing online 914 community!
We have it all, classifieds, events, forums, vendors, parts, autocross, racing, technical articles, events calendar, newsletter, restoration, gallery, archives, history and more for your Porsche 914 ...