[73XR-7owner]

i live at 2500 feet of elevation. the car was tuned for connecticut, probably a hundred feet above sea level. i've noticed some hesitation until the car is well warmed up, like half an hour of running. could it be the elevation? think it's too lean for these mountains?

if so, the next question is, how difficult is the adjustment? should i try it myself or take it to my mechanic?

and then there's gasoline. i'm running citgo 93 octane. the previous owner said it prefers sunoco 94, but the nearest sunoco is 40 miles away. at ten miles to the gallon, i'd spend all my gas and time driving back and forth to the pumps. does anyone know of a website or elsewhere that lists the comparative qualities of various gasoline brands? my three choices locally are citgo, getty, and exxon.

 

[clevelandcougar]

The problem is more than likley the elevation. I live in Northern Colorado right up against the Rocky Mtns @ 5200+ elevation. Try richening up the fuel mixture. If that doesn't work, adjust the timing 1 degree for every 1000 feet of elevation (can't remember if you should advance or retard, thinking that it's retard). You may need to rejet your carb, I have never done this and don't know how complicated it would be. Good Luck

_______________
'67 XR 7, 351 4V

 

[73XR-7owner]

thanks, cleveland...

adjusting the timing hadn't occurred to me and i doubt that's something i want to try. i also wonder if that would solve the hesitation but lead to other problems. once it warms up, it runs fine, very well in fact. would adjusting the timing negatively affect the performance when it's warmed up?

 

[Dom]

I have the same problem, I would like to try to adjust my timing, but the problem is that there are no marks on my block or timing chain cover. There is a mark on my crank pulley. How would I adjust it, and if I was going one way (retarting or advancing) how much would I move it?

 

[sixt9coug]

hm timing before the days of a timing light for me was done by turning the distributor until the RPMs rise to a peak. or until the engine just runs smoothest. or get a vacuum guage and hok it up to a port and turn the dist until you get th highst reading, then bak it off JUST A LIL BIT. on a 351 W i think you turn it cockwise to advance. thats what i do. but i have a tming light and i finaly used se white out o mark my balancer, so can actally see the marks on it now.

 

[sixt9coug]

damn i can't type LOL

 

[73XR-7owner]

new info on my setup...

the owner (finally) wrote back and told me he had the choke adjusted lean and a summer thermostat installed. first of all, i never heard of adjusting the choke lean, rich or otherwise. i thought it was either choked or not choked. he also said he doesn't advise adjusting the carb settings. i'm doubtful myself.

the thermostat could be the culprit though. my highest summer temperature is mid-80s. most of the year we are in the 60s or 70s. his summer is much warmer and he never drove it in winter, so it could take longer to warm up with that thermostat.

any hints on adjusting the choke?