Vince, How do you know your carbs haven't already been updated? I have owned many 300-Cs and the modifications had all been made. There was a carb modification kit in 1957 that dealers used to cure 'stumbling on turns' complaints in the early carbs. If your 300-C is later production, I would venture to say the mods have already been made, especially if you have no 'stumbling on turns'. Gary Hagy 300-C coupe 300-C conv. In a message dated 12/15/2008 8:58:05 A.M. Mountain Standard Time, vhelbling@xxxxxxxxxxxxxxx writes: I would like to try the modifications described in the Chrysler TECHNICAL BULLETIN #364 (or 384) dated 7/18/57. The change involves installing (4) metering rods #75-1160. Does anyone know a source? Or can anyone tell me the diameter of the rod at high speed (small diameter) and low speed (large diameter). Is there a cross reference chart available that shows chrysler numbers vs carter numbers on the metering rods. Does anyone have any info how this change worked in their car, especially regarding idle? I think I read somewhere that this change was incorporated into carburetors for 1958. Anyone have any advice? I have the motor on a running stand in the garage and will happily post results if I can get enough parts and info to try it. If the change is already in the 58 carbs, I could trade my spare 57 carbs. Vince in tampa bay [Non-text portions of this message have been removed] ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/Yahoo! Groups Links **************Make your life easier with all your friends, email, and favorite sites in one place. Try it now. (http://www.aol.com/?optin=new-dp&icid=aolcom40vanity&ncid=emlcntaolcom00000010) [Non-text portions of this message have been removed] ------------------------------------ To send a message to this group, send an email to: Chrysler300@xxxxxxxxxxxxxxx For list server instructions, go to http://www.chrysler300club.com/yahoolist/inst.htm For archives go to http://www.forwardlook.net/300-archive/Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/Chrysler300/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/Chrysler300/join (Yahoo! ID required) <*> To change settings via email: mailto:Chrysler300-digest@xxxxxxxxxxxxxxx mailto:Chrysler300-fullfeatured@xxxxxxxxxxxxxxx <*> To unsubscribe from this group, send an email to: Chrysler300-unsubscribe@xxxxxxxxxxxxxxx <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/