Club Cobra Keith Craft Motorsports  

Go Back   Club Cobra > Engine Building, Tuning, and Induction > Weber Tuning

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

Keith Craft Racing
Nevada Classics
Main Menu
Module Jump:
Nevada Classics
Nevada Classics
Keith Craft Racing
Advertise at CC
Banner Ad Rates
MMG Superformance
MMG Superformance
Keith Craft Racing
MMG Superformance
April 2020
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    

Kirkham Motorsports

Like Tree11Likes
  • 2 Post By 1985 CCX
  • 1 Post By 1795
  • 1 Post By crazycasey
  • 1 Post By 1795
  • 2 Post By Morris
  • 1 Post By crazycasey
  • 1 Post By razerwire
  • 1 Post By razerwire
  • 1 Post By Gaz64

Reply
 
LinkBack Thread Tools Display Modes
  #1 (permalink)  
Old 02-19-2020, 11:07 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jan 2020
Location: Cotati, CA
Cobra Make, Engine:
Posts: 11
Not Ranked     
Default Weber Air Filters

Hey gang,

Im setting up some 48 IDAs for a 289 in a Mustang, that will eventually make its way into a 289 FIA car. The Mustang has little more room for an air cleaner than I would assume the Cobra would have, so the discussion may be relevant.

What are you all running for air cleaners? Most of the photos I see have either the screen that pops into the velocity stack (sold by Redline), or the mesh screen that pops over the velocity stack (black band around the bottom). Based on my rudimentary measurements, I dont think I have room for something like a K&N (even the shortest one). Ive seen a few people running the foam disc type filters, though Ive heard theyre terribly restrictive. Ive seen no one running UNI filters, which surprises me because they actually work pretty good on motorbikes. Is there anything that Im missing?

What would also be great, is if folks would post what effect whatever type of filter they ended up going with had on their jetting.

Thanks for reading!

Casey
Reply With Quote
Sponsored Links
Sponsored Links
  #2 (permalink)  
Old 02-19-2020, 11:29 AM
1985 CCX's Avatar
CSX2375R Comp289
Visit my Photo Gallery

 
Join Date: Mar 2005
Location: Manchester, NH
Cobra Make, Engine: AK1085 and CSX2375R: Competition tribute in vintage Hertz Gold
Posts: 15,800
Not Ranked     
Default

I run mine open, screens could help but its about the air intake and velocity.
There are folks that run the filters and I am unsure of how that works. I find restricting the air flow causes flooding. When I use a nylon sock with a fine mesh it is fine around town, problem comes when you hit the units wide open.
=FLOODING

So I am in year 6 with wide open stacks, screens would keep out large rocks but the fine dust dirt is no doubt the biggest issue.

My $0.02
1795 and crazycasey like this.
Reply With Quote
  #3 (permalink)  
Old 02-19-2020, 01:09 PM
t walgamuth's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: Jan 2018
Location: Lafayette, IN
Cobra Make, Engine: Looking to buy
Posts: 896
Not Ranked     
Default

I have K and N on mine but have not actually been able to run it that way. I can testify that they do stick up pretty high.
__________________
Cobra loving, autocrossing Grandpa Architect.
Reply With Quote
  #4 (permalink)  
Old 02-19-2020, 01:48 PM
1985 CCX's Avatar
CSX2375R Comp289
Visit my Photo Gallery

 
Join Date: Mar 2005
Location: Manchester, NH
Cobra Make, Engine: AK1085 and CSX2375R: Competition tribute in vintage Hertz Gold
Posts: 15,800
Not Ranked     
Default

It's a situation if your car sits the motor like an original.
Weber's sit high in a FIA/SS buggy spring frame, cleaners might not clear the hood.
Mine are the slightly taller alloy horns however it only leaves a 1" gap for cleaners to mount.
Reply With Quote
  #5 (permalink)  
Old 02-19-2020, 01:56 PM
1795's Avatar
CC Member/Contributor
Visit my Photo Gallery
Gold Star Contributor
 
Join Date: Aug 2013
Location: Bristol, NY
Cobra Make, Engine: SPF MKII Riverside Racer FIA
Posts: 1,754
Not Ranked     
Default

Like Jeff (1985 CCX), I run with them open, albeit mine is just a race car. I was running the mesh screens initially but was told that even they are restrictive and will cost you about 50 HP. I can attest to that, as after I removed the screens there was a huge gain in performance.

If you will be driving in sandy areas or on gravel roads you might want some filtering. With a race car I am rebuilding the engine every couple of years so getting a little dust in there is not as concerning.
crazycasey likes this.
__________________
Reply With Quote
  #6 (permalink)  
Old 02-20-2020, 08:35 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jan 2020
Location: Cotati, CA
Cobra Make, Engine:
Posts: 11
Not Ranked     
Default

Quote:
Originally Posted by 1985 CCX View Post
When I use a nylon sock with a fine mesh it is fine around town...
So I am in year 6 with wide open stacks...
Are you talking like, women’s hosiery? Could be a good idea to keep some in the glovebox for when you encounter a dusty road I suppose...

In 6 years have you experienced any real detriment to running open stacks? More frequent oil changes maybe? Any compression loss?

Quote:
Originally Posted by 1795 View Post
With a race car I am rebuilding the engine every couple of years...
So, I am VERY curious about this. Back in the day folks ran chrome (chromoly) rings in dusty conditions. They’d last longer than cast rings, but would also wear the cylinders faster. My 289 has plasma moly rings that are supposedly pretty unforgiving in dirty conditions...

When you rebuild so often, are you able to “ring and bearing”, or are you finding the added abrasive in the system is wearing bores and journals too? What about valve guides? I would be very curious to take apart a motor with a couple years of use in dusty conditions just to see how much of the cautionary aspect of filtration holds true.
BigGuy likes this.

Last edited by crazycasey; 02-20-2020 at 09:39 AM..
Reply With Quote
  #7 (permalink)  
Old 02-20-2020, 02:53 PM
1795's Avatar
CC Member/Contributor
Visit my Photo Gallery
Gold Star Contributor
 
Join Date: Aug 2013
Location: Bristol, NY
Cobra Make, Engine: SPF MKII Riverside Racer FIA
Posts: 1,754
Not Ranked     
Default

Have not run in any real dusty conditions. Typical rebuild/refreshing is rings, bearings, valve springs and seals. Running an aggressive cam at high rpms on a continuous basis is tough on the springs, bearings and rings.

Jeff i right in that if you have an original style transverse leaf spring suspension, there is not a lot of clearance to the hood from the horns.
crazycasey likes this.
__________________
Reply With Quote
  #8 (permalink)  
Old 02-20-2020, 05:43 PM
CC Member
Visit my Photo Gallery

 
Join Date: Dec 2003
Location: Gurnee, IL
Cobra Make, Engine: Kirkham #259
Posts: 1,194
Not Ranked     
Default

Filters should always be used on motors....even if it’s a air box around the Weber’s with a filtered input opening.....

All of our race motors used filtration on air intake and we rebuilt based on the leak down test after every race.....usually every 10 hours we’d rebuild the motor because the valve would leak the most....which is dirt coming in thru the air intake .....once our leak down got to 15% to 20%...we’d rebuild motor....ingesting dirt/dust & reversion is the common component for loosing HP.....
Gaz64 and crazycasey like this.
__________________
Morris
Reply With Quote
  #9 (permalink)  
Old 02-20-2020, 09:23 PM
CC Member
Visit my Photo Gallery

 
Join Date: Sep 2008
Cobra Make, Engine: csx4163 full comp alu. body
Posts: 358
Not Ranked     
Default

ITG filters are used by some. I have them on my engine. I wish I could find older thread with pictures of the engine showing filters, on and off, taken on Kroyer chassis dyno. Pictures had closeup in high definition.
Reply With Quote
  #10 (permalink)  
Old 02-21-2020, 07:20 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jan 2020
Location: Cotati, CA
Cobra Make, Engine:
Posts: 11
Not Ranked     
Default

Quote:
Originally Posted by razerwire View Post
ITG filters are used by some...
Are they run in a manner similar to this?

(Im trying to glean some more info from this gentleman over on the VMF forum.
Attached Images
 
Reply With Quote
  #11 (permalink)  
Old 02-21-2020, 08:21 AM
1985 CCX's Avatar
CSX2375R Comp289
Visit my Photo Gallery

 
Join Date: Mar 2005
Location: Manchester, NH
Cobra Make, Engine: AK1085 and CSX2375R: Competition tribute in vintage Hertz Gold
Posts: 15,800
Not Ranked     
Default

FYI SAI did not use filters either
Reply With Quote
  #12 (permalink)  
Old 02-21-2020, 09:00 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jan 2020
Location: Cotati, CA
Cobra Make, Engine:
Posts: 11
Not Ranked     
Default

Quote:
Originally Posted by 1985 CCX View Post
FYI SAI did not use filters either
Neither did they wear rubbers, I’d wager.

I mean, I’m not trying to be a jerk...just pointing out that the thinking has changed on some things...
1985 CCX likes this.

Last edited by crazycasey; 02-21-2020 at 10:13 AM..
Reply With Quote
  #13 (permalink)  
Old 02-21-2020, 10:43 AM
CC Member
Visit my Photo Gallery

 
Join Date: Sep 2008
Cobra Make, Engine: csx4163 full comp alu. body
Posts: 358
Not Ranked     
Default

Yes, I lightly oil them and have washed them. Four dealers in States now. Part number JC70/JC71
crazycasey likes this.

Last edited by razerwire; 02-21-2020 at 10:48 AM..
Reply With Quote
  #14 (permalink)  
Old 02-21-2020, 01:39 PM
BigGuy's Avatar
CC Member/Contributor
Visit my Photo Gallery
Gold Star Contributor
 
Join Date: Dec 2003
Location: Macedonia, OH, OH
Cobra Make, Engine: CSX4xxx, Alum. Shelby 427 w/ Webers, and 1959 Corvette Convt.
Posts: 16,057
Not Ranked     
Default

Is that part number for the screens or filters?

Thanks,
__________________
Jon
-----------------
Reply With Quote
  #15 (permalink)  
Old 02-21-2020, 04:53 PM
CC Member
Visit my Photo Gallery

 
Join Date: Jan 2020
Location: Cotati, CA
Cobra Make, Engine:
Posts: 11
Not Ranked     
Default

Quote:
Originally Posted by razerwire View Post
Yes, I lightly oil them and have washed them. Four dealers in States now. Part number JC70/JC71
Do you run the bases with a grommet like the picture I posted, or do you bolt them to the velocity stack hold-down/jet well location? I ask because I only have 1 of clearance over the stacks at my tightest spot, and I know ITGs want a 3/4 gap between the stack and the inside of the filter. If I set them where they want to be, the bases are going to be sitting right on top of the jet well screens. If I bolt the bases to the carb bodies, Im going to be a little tight on the clearance to the inside of the filter (about 5/8 according to the dimensions published online).

Thanks for your help!
Reply With Quote
  #16 (permalink)  
Old 02-21-2020, 05:50 PM
CC Member
Visit my Photo Gallery

 
Join Date: Sep 2008
Cobra Make, Engine: csx4163 full comp alu. body
Posts: 358
Not Ranked     
Default

https://imgur.com/a/f7J6D
If you click on pictures they get bigger. one side of filter/screen hooks on and three quick screws hold it on. Hope I answered both questions. Foam and screen are bonded
crazycasey likes this.
Reply With Quote
  #17 (permalink)  
Old 02-22-2020, 03:04 AM
Gaz64's Avatar
CC Member
Visit my Photo Gallery

 
Join Date: May 2008
Location: Brisbane, QLD
Cobra Make, Engine:
Posts: 2,371
Not Ranked     
Default

Quote:
Originally Posted by crazycasey View Post
Do you run the bases with a grommet like the picture I posted, or do you bolt them to the velocity stack hold-down/jet well location? I ask because I only have 1 of clearance over the stacks at my tightest spot, and I know ITGs want a 3/4 gap between the stack and the inside of the filter. If I set them where they want to be, the bases are going to be sitting right on top of the jet well screens. If I bolt the bases to the carb bodies, Im going to be a little tight on the clearance to the inside of the filter (about 5/8 according to the dimensions published online).

Thanks for your help!
You would do better with something like this:
https://www.merlinmotorsport.co.uk/f..._tray_dims.pdf
Allows the base to be fitted flat without the screens, don't need them since they will be supplied with filtered air.

Also allows much easier jet removal than some other setups.
crazycasey likes this.
__________________
Gary

Gold Certified Holden Technician
Reply With Quote
  #18 (permalink)  
Old 02-22-2020, 08:32 AM
CC Member
Visit my Photo Gallery

 
Join Date: Jan 2020
Location: Cotati, CA
Cobra Make, Engine:
Posts: 11
Not Ranked     
Default

Quote:
Originally Posted by Gaz64 View Post
You would do better with something like this:
After looking at some of these pics I’m amazed at how much room some of the Cobras have. I have 1” at the lowest point from the top of my stack to the underside of the hood. Going by the measurements online, if I flat mount the bases (I’m going to have to dimple them or something to clear the needle valve plug) I will have 5/8” above the stack and the filter itself will just touch the bottom of the hood. Certainly not ideal, but I don’t see any other way to do it other than to try and lower the engine.

Last edited by crazycasey; 02-22-2020 at 08:35 AM..
Reply With Quote
  #19 (permalink)  
Old 02-22-2020, 09:59 AM
CC Member
Visit my Photo Gallery

 
Join Date: Sep 2008
Cobra Make, Engine: csx4163 full comp alu. body
Posts: 358
Not Ranked     
Default

Would there be enough material to mill top of manifold to lower carbs?
Reply With Quote
Reply

Thread Tools
Display Modes

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 02:03 AM.


Powered by vBulletin® Version 3.8.0
Copyright ©2000 - 2020, 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
Links monetized by VigLink