The Stovebolt Site Forums The Shop Area Engine Shop Adjusting for different elevation and other issues

I recently got transferred from southeast Oklahoma to White Sands Missile Range in New Mexico. I'm planning to bring my 58 out in the next month or two. In Oklahoma the elevation was about 770 feet above sea level. Here at White Sands we're at about 4100 feet, with a climb up to around 5800 feet going through the pass to get to the nearest city of Las Cruces.

Is a simple carb adjustment all I'm looking at to keep things running right, or will I need to adjust timing and possibly rejet the carb? Original 235 and Rochester carb.

I'll also be switching from straight gas to E10, since that's all that seems to be available out here. I've read a lot of you guys are using E10 with no problems. I've still got the original gas tank in my truck. Is the E10 going to act like a solvent and cut loose nearly 60 years worth of gasoline varnish from the inside of the tank and gum everything up? Will the Rochester carb handle E10 with no problems?

We lived in N.M.for years(7000 feet). Dads 50 was just fine(no fussing with any thing) I live at 5000 feet here in sunny Utah. Often drive over a 10000 foot pass to visit friends. Still tune to the book and still have a stock Rochester. A non issue. You will notice a small drop in power, thin air. No need to re-jet. Might need to make a small adjustment to timing, if it pings. And you might not need to do anything.

Thanks Steve. Growing up I'd always heard that people had to stop and readjust things on long trips where major elevation changes were involved. I've never taken my truck out of SE Oklahoma before and all the newer fuel injected stuff adjusts automatically, so it's something I've never dealt with.

Normally it helps to lean out the carb with the idle screw(that only addresses the idle circuit) and advance the timing slightly, say 3 degrees. One can also mill the heads .060" or so, or get higher CR Pistons.