[phpBB Debug] PHP Warning: in file [ROOT]/includes/bbcode.php on line 112: preg_replace(): The /e modifier is no longer supported, use preg_replace_callback instead
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4752: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3887)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4754: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3887)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4755: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3887)
[phpBB Debug] PHP Warning: in file [ROOT]/includes/functions.php on line 4756: Cannot modify header information - headers already sent by (output started at [ROOT]/includes/functions.php:3887)
Racing Fuel Systems • View topic - 750 Mighty Demon hard to start

750 Mighty Demon hard to start

Re: 750 Mighty Demon hard to start

Postby rgalajda » Sat Sep 11, 2021 10:02 am

I was looking back at your posts to see if you mentioned IFR size . was it .033" ? and .076" IAB
I would think that is to lean . Even if it idles ok after warmed up ( heat soaked ) it's probably to lean for start up.
Some 750 holleys came originally with IFR .038" and .070" IAB . The bigger the venturi , the bigger the IFR. Grumpy cams ( low vacuum ) require more idle fuel. Less signal to pull the fuel.
I would go to at least IFR .036" - >038" and .070" IAB. That would be close to what the 750 Mighty Demon had originally.
As someone else mentioned , check the passage is drilled ( clean ) while your at it.

As for chokes. Even at 90 degrees ambient temp a properly set electric choke will still close on a cold engine ( just not as tightly ) and open very quickly on start up greatly assisting the start up of a grumpy cam.
rgalajda
 
Posts: 373
Joined: Sat Mar 20, 2021 8:21 am
Location: Ontario,Canada

Re: 750 Mighty Demon hard to start

Postby 2x4b4fun » Sun Sep 12, 2021 2:56 pm

User avatar
2x4b4fun
 
Posts: 18
Joined: Fri Jan 15, 2021 11:01 pm

Previous

Return to Holley

Who is online

Users browsing this forum: No registered users and 1 guest

cron