Quote:
|
Originally Posted by Jacob
Brian,
Wouldn’t a turbocharger negate any difference in air density?
Here at 5000ft, my ‘83TD (4 speed conversion) runs about 27mpg beating around town and better than 30mpg on the highway to San Antonio if I can stay under 80mph.
Jacob
|
A turbo
could negate any difference in air density, however, the turbo doesn't know that you are now at 5000 feet with an atmospheric pressure of 12 psi. It reaches it's maximum boost of 13 psi and you get a total absolute pressure in the manifold of 25 psi. Compare this to sea level where you get a total absolute pressure of 27.7 psi. The difference, 10%, is much less than a n/a engine would suffer.
If you wanted to have the exact same power at 5,000 feet, you'd need to crank up the wastegate to provide 15.7 psi. If the ALDA could provide sufficient fuel, and this is doubtful, the vehicle would perform exactly the same as it would at sea level. But, it would not be adviseable to return to sea level with the boost set at 15.7 psi.