Spring build comes early
#231
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Scrapping out my tune and starting over from scratch. Wow, was I off with this new setup. All numbers in the upper left histogram are to be between -5 and +5
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Will finish this up next week.
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Will finish this up next week.
#233
Senior Member
True Car Nut
#240
DINOSAURUS BOOSTUS
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The basics...
Dan had tuned his car when it had rockers. It was also tuned for summer/fall. Now it'* winter (much colder) and the density of the air is different. Then along comes Dan and he changes the amount of air that flows through his motor by camming it. Now his tune is way out of whack for the cam and weather changes. He'* saying it'* time to tune it from step one.
This is a good approach whenever you make a good change to the car.
This helps back up what was mentioned earlier in the thread. We like to say rockers and a cam are similar for power etc. Realism that they are very different. Rockers open the valves further (lift) to allow more air into the cylinders. A cam changes timing, lift, and duration as well as overlap of the intake and exhaust valves. A cam changes everything about the motor and the way it runs.
Dan had tuned his car when it had rockers. It was also tuned for summer/fall. Now it'* winter (much colder) and the density of the air is different. Then along comes Dan and he changes the amount of air that flows through his motor by camming it. Now his tune is way out of whack for the cam and weather changes. He'* saying it'* time to tune it from step one.
This is a good approach whenever you make a good change to the car.
This helps back up what was mentioned earlier in the thread. We like to say rockers and a cam are similar for power etc. Realism that they are very different. Rockers open the valves further (lift) to allow more air into the cylinders. A cam changes timing, lift, and duration as well as overlap of the intake and exhaust valves. A cam changes everything about the motor and the way it runs.