Can you hear the difference between low and high compression
Originally Posted by stockA4
Dynamic vs static compression via the Intake Valve Closing point determines whats trapped at low speed so in the video with the cam being the same all the compression lost was also dynamic. An early exhaust opening point makes it sound tougher and then there's that overlap lol
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Joined: Jul 2019
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From: Tasmania Australia
A friend of mine told an amusing story of his friends girlfriend they were stopped at the traffic lights recently listening to a vehicle with a hot lumpy idle beside them waiting for the lights to change, she commented with surprise that there must be something terribly wrong with the car to sound like that. He her partner was trying unsuccessfully to explain to her that it was normal for that car and more than that, it was even desirable.
She was not easily convinced, in her mind the car was just not running well. She finally conceided that some may like it but added; "well I hope you never get a car like that"
She was not easily convinced, in her mind the car was just not running well. She finally conceided that some may like it but added; "well I hope you never get a car like that"
Last edited by TimsLS1; Feb 21, 2020 at 04:37 PM.
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From: St. Louis
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Darth, were you able to run both setups on 93 pump?
On the 12.6 build, I popped a hole in one of the heads, and that kind of spiraled out from there, but it was not related to compression or fuel. It was related to a pushrod mis-installation.
Launching!
Joined: Jun 2020
Posts: 214
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From: San Diego
With compression comes good race gas.
You can smell 110 leaded fuel compared to unleaded fuel.
My road race engine has 13 to 1 compression.
So to start it and save the battery and starter there is a procedure.
Leave Ignition off.
Spin starter till there is oil pressure.
Then while it is still spinning on the starter turn on ignition.
Fires right up.
The throttle response is amazing on the race car.
Maybe a lot of that is the very small flywheel with a dual disc 7 inch clutch.
With a dog ring box the clutch is not used on upshifts just on heal toe downshifts and in the pits.
In the pits is where it experiences the most clutch wear.
Throttle by wire cars are just programmed with lazy throttle response.
But that can be modified.
Scca let some classes mod the throttle by wire just so the engine would rev quicker for heal and toe down shifts.
You can smell 110 leaded fuel compared to unleaded fuel.
My road race engine has 13 to 1 compression.
So to start it and save the battery and starter there is a procedure.
Leave Ignition off.
Spin starter till there is oil pressure.
Then while it is still spinning on the starter turn on ignition.
Fires right up.
The throttle response is amazing on the race car.
Maybe a lot of that is the very small flywheel with a dual disc 7 inch clutch.
With a dog ring box the clutch is not used on upshifts just on heal toe downshifts and in the pits.
In the pits is where it experiences the most clutch wear.
Throttle by wire cars are just programmed with lazy throttle response.
But that can be modified.
Scca let some classes mod the throttle by wire just so the engine would rev quicker for heal and toe down shifts.
Last edited by Passmenow; Feb 24, 2022 at 09:38 AM.
