Absolute Pace

Welcome to Club Cobra.

You are currently viewing the world's largest resource for Shelby related information as a guest which gives you limited access to view most discussions, articles and access our other FREE features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload your own photos and access many other special features. Registration is fast, simple and absolutely free so please, join our community today!


Go Back   Club Cobra > Club Forums > Australian Cobra Club

Welcome to Club Cobra!  The World's largest non biased Shelby Cobra related site!

  •  » Representation from nearly all Cobra/Daytona/GT40 manufacturers
  •  » Help from all over the world for your questions
  •  » Build logs for you and all members
  •  » Blogs
  •  » Image Gallery
  •  » Many thousands of members and nearly 1 million posts! 

YES! I want to register an account for free right now!  p.s.: For registered members this ad will NOT show

MMG Superformance
Nevada Classics
Keith Craft Racing
Main Menu
Nevada Classics
Nevada Classics
MMG Superformance
Advertise at CC
Banner Ad Rates
MMG Superformance
Keith Craft Racing
September 2018
S M T W T F S
            1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29
30            
  #1 (permalink)  
Old 08-05-2017, 07:03 PM
snakesaway's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Jun 2014
Location: Melbourne, Vic
Cobra Make, Engine: Evans and Wooley, 302 Windsor, Supra turbo 5sp
Posts: 92
Not Ranked     
Default Mild 302 carby size and fuel consumption

Hi all,

I currently have a mild 302 windsor that runs the following configuration.
30 thou over bore
Edelbrock Performer RPM manifold
Scorcher distributor
Cam is TRW TP205 (intake lift .472 duration 290) (exhaust .406 lift & 300 duration)
Holley 600 or 650 CFM carby

I have couple of issues

Not sure what CFM the carby is. As some highly intelligent individual in the past has filed off the model number on the choke tower The size comes from talking to AFD and using the numbers from the primary and secondary butterflies as a guide to CFM size.

I am getting about 20lt per 100 km which I feel is probably a bit high. I was speaking to my uncle who over the years has owned a wide and weird collection of vehicles, he too feels it is high.

I have a vacuum whistle that is coming from the carby once it is heated up.

Therefore with these to issues in mind I guess I have 2 options.

A carby rebuild. Hopefully to find out more info as to the carby size, jet size and accelerator pump size. Fix the whistle (gaskets) and perhaps armed with current jet size and accelerator pump size if these are wrong put the correct ones in and possibly improve fuel economy not that I ever expect it to great.

Or a new carby if so what are peoples recommendations I have looked at Holleys website and it recommends a carby between 570 and 650 CFM. They have various model Street Avernger, Brawler, Classic, Quickfuel and Slayer. I went through them all and are suitably confused as to what CFM or type to use. So if people some experience with any of the above your thoughts would be appreciated.

Cheers

Andrew
Reply With Quote
Sponsored Links
Sponsored Links
  #2 (permalink)  
Old 08-06-2017, 06:40 AM
LoBelly's Avatar
Senior Club Cobra Member
Visit my Photo Gallery

 
Join Date: Feb 2006
Location: Melbourne, VIC
Cobra Make, Engine: RMC, carb 347 TopLoader and Jag running gear ~ so old school I time it with an hour-glass :D
Posts: 1,285
Not Ranked     
Default

Hello Andrew

In very round figures, at 6000 rpm the 302ci is pumping about 525cfm, about 612cfm @ 7000rpm.
(1 cfm = 1728cim)

The Holley recommendation therefore appears to correct (as you'd expect).

When it came time to replace my aged and wobbly 700 double pumper I looked at the cost of refurbishing myself against a factory refurbished carburetor and decided that with the state of my carburetor and the number of things I wanted replaced - getting a refurbished carburetor was cheaper.

Holley has an ebay store where they sell factory refurbished carbs, I bought one, it arrived looking new and it has worked very well after a bit of tuning.

http://stores.ebay.com.au/Holley-Performance

Your main choice will be between vacuum secondaries or a double pumper.

There are some nice 600 double pumpers or vac secondary 4 barrels currently listed that I think would suit nicely.

Personally I would keep it simple and get something like this:
Holley 0-4776S 600CFM Shiny Double Pumper Factory Refurbished 4bbl

If you're worried about the fuel economy then maybe look at the vac secondary equivalent.

Come to the AGM and talk carburetors - you'll get plenty of input.

Apologies to all the carburetor gurus for the forgoing massive over-simplifications.

Good luck Andrew.

LoBelly
Reply With Quote
Reply


Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are On
Pingbacks are On
Refbacks are On



All times are GMT -7. The time now is 08:53 PM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Search Engine Friendly URLs by vBSEO 3.6.0
The representations expressed are the representations and opinions of the clubcobra.com forum members and do not necessarily reflect the opinions and viewpoints of the site owners, moderators, Shelby American, any other replica manufacturer, Ford Motor Company. This website has been planned and developed by clubcobra.com and its forum members and should not be construed as being endorsed by Ford Motor Company, or Shelby American or any other manufacturer unless expressly noted by that entity. "Cobra" and the Cobra logo are registered trademarks for Ford Motor Co., Inc. clubcobra.com forum members agree not to post any copyrighted material unless the copyrighted material is owned by you. Although we do not and cannot review the messages posted and are not responsible for the content of any of these messages, we reserve the right to delete any message for any reason whatsoever. You remain solely responsible for the content of your messages, and you agree to indemnify and hold us harmless with respect to any claim based upon transmission of your message(s). Thank you for visiting clubcobra.com. For full policy documentation refer to the following link: CC Policy