A/F ratios

Old 02-22-2008, 05:03 PM
  #1  
suicidebomb
Senior Member
RACING JUNKIE
Thread Starter
 
Join Date: Jul 2007
Location: Independence, Missouri
Posts: 1,181
Default A/F ratios

How lean can one go and still not get into detanation in a N/A engine on methanol? For instance in my sbc 406 about 4.75/1 is as lean as i have tried. I still get quite a bit of oil dilution, so i assume I am still pretty rich, but I am afraid to go much leaner for fear of burning a hole in a piston. does anyone know if I can go, say 5/1 or maybe a little more 5.25/1 and still be safe, and maybe solve some of the dilution or at least cut back on it some.
suicidebomb is offline  
Old 02-22-2008, 05:15 PM
  #2  
johnracer
Senior Member
DYNO OPERATOR
 
Join Date: Aug 2005
Location: Rifle Colorado
Posts: 585
Default

I don't really know about a/f ratios, but, if it were mine. I'd tune it to run the best and quit worrying about it...
johnracer is offline  
Old 02-22-2008, 06:43 PM
  #3  
suicidebomb
Senior Member
RACING JUNKIE
Thread Starter
 
Join Date: Jul 2007
Location: Independence, Missouri
Posts: 1,181
Default

4.75/1 was its best E.T. and speed to date, and I would like to try it leaner, but I am worried about burning my engine down. However, I still appreciate your input, thanks.
suicidebomb is offline  
Old 02-22-2008, 10:50 PM
  #4  
zipper06
Senior Member
RACING JUNKIE
 
Join Date: Jan 2006
Location: La.
Posts: 2,890
Default

Originally Posted by suicidebomb
4.75/1 was its best E.T. and speed to date, and I would like to try it leaner, but I am worried about burning my engine down. However, I still appreciate your input, thanks.
Where did you get these #'s from?, you need to run an EGT and keep the #'s around 1100 degrees on topend. if you go leaner than that you will burn something down.

JMO

Zip.
zipper06 is offline  
Old 02-23-2008, 03:15 AM
  #5  
johnracer
Senior Member
DYNO OPERATOR
 
Join Date: Aug 2005
Location: Rifle Colorado
Posts: 585
Default

Don't be afraid to lean it out. You'd have to go really, REALLY lean to hurt it unless you're running nitrous or some sort of forced induction with a lot of boost....
johnracer is offline  
Old 02-23-2008, 03:21 AM
  #6  
johnracer
Senior Member
DYNO OPERATOR
 
Join Date: Aug 2005
Location: Rifle Colorado
Posts: 585
Default

Another thought, if you're injected, the oil delution could be the barrel valve adjustment, or running the engine too cold w/carb or injection...
johnracer is offline  
Old 02-23-2008, 04:24 AM
  #7  
Tod74
Senior Member
RACING JUNKIE
 
Join Date: Sep 2007
Posts: 4,137
Default

Like ZIP said you need an EGT.
Tod74 is offline  
Old 02-23-2008, 04:35 AM
  #8  
suicidebomb
Senior Member
RACING JUNKIE
Thread Starter
 
Join Date: Jul 2007
Location: Independence, Missouri
Posts: 1,181
Default

Where can I get an EGT?
suicidebomb is offline  
Old 02-23-2008, 04:37 AM
  #9  
Tod74
Senior Member
RACING JUNKIE
 
Join Date: Sep 2007
Posts: 4,137
Default

http://www.ronsfuel.com/accessories.cfm
Tod74 is offline  
Old 02-23-2008, 08:41 AM
  #10  
zipper06
Senior Member
RACING JUNKIE
 
Join Date: Jan 2006
Location: La.
Posts: 2,890
Default

Also here for duel setup $300.00

Zip.

http://www.exhaustgas.com/ProductDet...ID=sub2&RepID=
zipper06 is offline  

Contact Us - Archive - Advertising - Cookie Policy - Privacy Statement - Terms of Service - Do Not Sell My Personal Information -