Mike @ New Era

iTrader: (10)

Yeah I do lol. However, we don't have any customers local that drive their heavily modified supercharged vehicles during winter time. And I am yet to drive my truck through a winter here, that will change next year though. I just mainly know this from my experience tuning cars/trucks all over the world in all different environments.

ou812sm

iTrader: (16)

Can someone explain D/A and how it will effect boost

Vortec350ss

iTrader: (20)

D/A is density altitude. The bottom line is cars perform better in more dense air. The higher in elevation you get, the more thin the air is. Things like temperature, barometric pressure, and Humidity also have a huge effect on the density of air. DA converts current air conditions to an equivalent altitude. Since we see such low temps and high baro pressure during the winter we reguarly see very negative relative altitude. Basically, this AM being so cold it would be like driving your car in a -3200' valley... and believe me when I say I could tell! It makes a HUGE difference in how a car performs. Since a blower compresses what is available to it, when the air is 5% more dense, it will make 5% more boost on top of its more dense starting point (rough math and its not exact of course... but you get the idea). Its the exact opposite effect in the dead of summer with the heat and humidity we see here.

Here is a full description of it:
Density altitude - Wikipedia, the free encyclopedia

A negative DA is a racers best friend!

ou812sm

iTrader: (16)

Ah OK got it thank you