The later model carbs have a big issue of a vacuum leak in the hose that goes to the lower front of the carb (where the power valve lives) When it leaks vacuum, the carb dumps extra gas. Earlier ones had the port internal with less chance of leakage (and easier to overhaul too!) I got a steady 18 mpg with my '73 J4000 on 33" tires with a '77 AMX 304, TH400 auto, QT with PT/OD kit and 3.73 gearing (seems to be the magic mix for AMCs that freeway cruise a lot AND haul loads) I can hardly wait to see how it goes with EFI in the replacement trucks! Oh, and for vehicles that prefer hi-test, I suggest LPG conversions if the cost isn't close to equal or more than gas in your area! Jim Blair, Lynnwood, WA '87 Comanche, '83 Jeep J10, '84 Jeep J10 From: "jerijan baldwin" <jerijan@xxxxxxxxxxx> Subject: Re: [Amc-list] Question on 2BBL aftermarket carbs - 91 GW To: "'AMC/Rambler owners, drivers and fans.'" <amc-list@xxxxxxxxxxxx> Message-ID: <CFB87EAE6F78476F99B2EBB55AD20E42@thehoneymooner> Content-Type: text/plain; charset="us-ascii" There is a conversion Edlebrock 4V for the GrandWagoneer...everyone I know who's had experience with it (I have not) has been quite happy since the over the road MPG increases with the 4V when you keep your toes out of it... (Apparently the smaller primary venturis are responsible for that effect although it does kind of contradict what you'd expect). Put your toes into it and you'll have no misunderstanding about what else that carb does... Power increase is enourmous (according to said feedback), 'good running' traits (as in 'smoothness', reliable adjustments remaining in adjustment, emissions, etc, etc) are exponential, but the payoff is single digit MPG (which on the GrandWagoneer is legendary already). If I could find a decent used conversion, I'd do it in an instant because the 2V carb is a crappy one and ANY increment in MPG on the GrandWagoneer is a blessing. I don't use mine unless there is an absolute need to (like 55 feet of snow or something) because I do believe the oil companies already have all the support and gold they will ever get from me and then some. Since their profits are obscene (incremented hugely over the base cost of crude) it is my policy to admire the Hoggiest members of my fleet whilst they are at rest (and this, sadly, includes my '62 Ambassador; I could never get that thing to do much better than 14 (if that) and, to make matters worse, it just loves 'Ethyl' (Ok, it ain't tetraEthylLead anymore, but Hi-Test all the same)... How I do wish there were a way to make that car cheaper to operate, but...Oh, well... *sigh* When gasoline was $0.35 a gallon, that Ambassador was fine and fun. Now it's just 'Fine'. Jj _________________________________________________________________ Need to know the score, the latest news, or you need your Hotmail®-get your "fix". http://www.msnmobilefix.com/Default.aspx -------------- next part -------------- An HTML attachment was scrubbed... URL: http://splatter.wps.com/pipermail/amc-list/attachments/20080229/c59a4479/attachment.htm _______________________________________________ Amc-list mailing list Amc-list@xxxxxxxxxxxx http://splatter.wps.com/cgi-bin/mailman/listinfo/amc-list