73c20jim
Full Access Member
- Joined
- Jun 11, 2018
- Posts
- 2,282
- Reaction score
- 2,924
- Location
- Tombstone, AZ
- First Name
- Jim
- Truck Year
- 1973, 1973
- Truck Model
- C20 2WD Custom Deluxe. C10 2WD Base Model
- Engine Size
- 350 CID 195/260 HP Goodwrench crate, 400 CID 2bbl
I found out that all engine tuning specs are for sea level.
I'm at 4800 feet. All my driving is at this level, give or take a few hundred feet.
How much vacuum do I lose at this elevation?
ANSWERED: 1 inch of vacuum lost for each 1000 ft of elevation. I will be 4.8 inches of vacuum low.
How much more timing advance do I need? Some say bump it from 12 to 14.
ANSWERED: One degree advanced for each 1000 feet of elevation.
What else does altitude affect in tuning?
Truck is carburated with HEI ignition.
Do you agree with these answers.
I'm at 4800 feet. All my driving is at this level, give or take a few hundred feet.
How much vacuum do I lose at this elevation?
ANSWERED: 1 inch of vacuum lost for each 1000 ft of elevation. I will be 4.8 inches of vacuum low.
How much more timing advance do I need? Some say bump it from 12 to 14.
ANSWERED: One degree advanced for each 1000 feet of elevation.
What else does altitude affect in tuning?
Truck is carburated with HEI ignition.
Do you agree with these answers.
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