Results 1 to 6 of 6

Thread: new carb size ?

  1. #1
    Junior Member SHOW GUEST
    Join Date
    Mar 2009
    Posts
    2

    new carb size ?

    My 3500lb street strip 69 camaro has a Demon 850 mechanical secondary carb. I want to convert to e85. The 460" BBC has 13.0/1 pistons, 610 lift 255 duration cam and 410 gears. Should I consider a smaller, larger, or the same size carb? Thanks for your help.

  2. #2
    Senior Member RACING JUNKIE jmarksdragster's Avatar
    Join Date
    Jul 2007
    Location
    Florida
    Posts
    635
    If you still drive it on the street stick with the Demon. We did some dyno testing with a 1.500 venturi sleeved RS Demon I converted to run E85, made very good power.
    Mark Whitener
    http://racingfuelsystems.myfunforum.org
    __________

    Good work isn't cheap, and cheap work can't be good.

  3. #3
    Junior Member SHOW GUEST
    Join Date
    Mar 2009
    Posts
    2
    Thank you, sounds like good advice.

  4. #4
    Junior Member APPRENTICE
    Join Date
    Apr 2009
    Posts
    11

    I know the thread is sort of old but,

    I've considered the same thing myself and had a few questions.

    How much does jetting usually change when going to e85?
    How about air bleed changes?
    What is the range of CR that you should shoot for?

    Thanks, Steve

  5. #5
    Senior Member RACING JUNKIE jmarksdragster's Avatar
    Join Date
    Jul 2007
    Location
    Florida
    Posts
    635
    You can't just change jetting to go to E85, the metering blocks and boosters need mods in almost all cases to get enough fuel through. Jetting on an 850 will be high 90's to 100 with the appropriate mods to the carb. E85 does not need much emulsion either. And so far we've run up to 14.5 to 1 with no issues.
    Mark Whitener
    http://racingfuelsystems.myfunforum.org
    __________

    Good work isn't cheap, and cheap work can't be good.

  6. #6
    Junior Member APPRENTICE
    Join Date
    Apr 2009
    Posts
    11
    Thanks for the reply Mark, that's exactly what I wanted to know.

    Steve


Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Copyright © 2005-2016 RacingJunk.com All Rights Reserved.

Designated trademarks and brands are the property of their respective owners. Use of this Web site constitutes acceptance of the RacingJunk.com
Terms of Use, Classifieds Disclaimer, Privacy Policy, and Cookie Policy