Which Carb at 9000 ft?

[NewBird13]

Hey guys
Just got a steal on a rebuilt 390 but I need to get carburtor for it.
I live in Colorado at about 9000 ft above sea level. Does anyone have any suggestions on which carb would suit my needs? Leaning on the daily driver side so mpg is some what of a consideration but not essential.
Thanks

[Dan Leavens]

Sean at 9000 ft you need an " air induction " system not a carburetor LOL

[ncbird]

high altitude package

Having grown up in denver when carbs were the standar new cars coming into the state were spec'd with a "high altitude pkg". This was typically the same carb as normal but with smaller jets and possibly meteing rods. Some as I recall either had different vacuum advance and maybe weights. You might try the ford dealer in Grand Junction and see if any "senior" techs still remember. The other thing I would do is call Bandimere auto parts in Denver and ask for advice. They have been Colorado's strength in drag racing etc for decades including development of the nhra Bandimere drag strip.
I do remember a bar in crested butte with a fire pit in the middle of the floor and intereting little road that cut from there to Aspen. Grant

[c4clewis]

If you are going to be driving it down the mountain at any time, you might just consider a fuel injection system for driveability. I've heard nothing but good things about some of the newer plug & play systems like the Holley EZ EFI. All it takes is to switch out the carb (which you are planning on doing anyway), installing an O2 sensor in the exhaust, and some wiring. They are pretty slick systems.

[NewBird13]

I just checked them out, they are pretty slick!

[Guest]

Carb ...

As mentioned below, fuel injection would be the way to go if your going to see major changes in altitude. I also live in CO (7200') and am in the process of changing all my classic cars to EFI. In addition to automatic adjustment for altitude changes you get the added benefits of excellent cold start and idle, better fuel economy, and improved torque and HP over the entire rpm range. Mike

[NewBird13]

Yeah Im thinking that may be the way to go. Gaffney what are you using to do the conversion?

[simplyconnected]

Mike, I am pretty interrested too.
EFI does a great job of maintaining 14.7:1 air-to-fuel ratio, regardless of all other conditions. That produces optimum power across the whole rpm range.

The system will need a throttle body, throttle position sensor, injectors, a high pressure fuel pump, and usually a return line to the fuel tank. Oxygen sensors are relatively easy to install. Just buy a standard steel bung to weld into your exhaust pipe, and screw the sensor in.

With EFI, there is no choke and remote start systems work exceptionally well because the system requires no foot operation to open/close a choke. EFI systems automatically alter your spark and injector timing. Two more benefits emerge with EFI; no more vapor lock because the fuel is under positive pressure with a return line, and engine flooding is a thing of the past.

I'm all for it if the price is right. - Dave

[vote4pedro]

I was thinking about EFI on my 60' cuz it's always been easier for me then messing with carbs. Maybe i'm too new school but i don't mind the wiring and i like tuning with a computer.

the only reason i don't want to EFI is i would have to put a fuel return line in.

pete

[Guest]

Injection ...

Yeah Im thinking that may be the way to go. Gaffney what are you using to do the conversion?

I've been gathering components for over a year now for several different projects and am on my fourth book on system design and tuning. It's a fairly steep learning curve if you want to put together you own system from available oem and aftermarket pieces, but there are several plug and play returnless systems available. The FAST E-Z setup is one of the best proven systems out there and MSD has their Atomic system which is very similar to the FAST. Both are self learning and do not require laptop tuning. These systems run in the $2 to 2.5K range with everything you need for an easy one day install and be up and running.They both have four V throttle bodies with four built in injectors and are a wet intake, batch fire type setup. I picked up a FAST throttle body on ebay for cheap less the control unit and harness and will be trying to make it work with a modded GM computer for one of my vehicles the rest will be MPI setups scratch built. Time will tell how it will work out, but I should learn a lot along the way. Mike

[Astrowing]

In looking at several ford carb specs, it looks like they went down 2 thousanths for jets for every 5000 feet altitude.