Turbo?
cobraprince
08-06-2008, 07:18 PM
I am very new to turbos. And I have a lot of questions regarding them. Do I HAVE to increase the compression of my engine to add a turbo? And is there a specific type of turbo that I HAVE to use with my car? I have 1978 plymouth Volare with a slant six(225) in it.
KManiac
08-06-2008, 07:54 PM
Basic Turbo 101:
A turbo charger uses waste exhaust gases to drive the impeller of a pump that increases the pressure of the intake gases going into the cylinders. The increase pressure in the cylinders from the turbo act like a temporary increase in mechanical compression ratio when under boost.
Do you HAVE to increase the mechanical compression ratio before you install a turbo charger? NO! Keep it the same or even decrease it a little if you want. Remember, the higher your mechanical compression ratio, the more stress is placed on the internal engine parts when a turbo is installed. Changing (decreasing) the mechanical compression ratio will require either installing a new head with larger combustion chambers or installing new pistons with concave dishes in the top or decreased deck height. Either way, decreasing or changing the mechanical compression ratio will require significant engine work.
I have not heard of anyone installing a turbo charger on a slant 6 before, but I am sure it has been done. Do research with after market turbo manufacturers to find the right set up for you.
A turbo charger uses waste exhaust gases to drive the impeller of a pump that increases the pressure of the intake gases going into the cylinders. The increase pressure in the cylinders from the turbo act like a temporary increase in mechanical compression ratio when under boost.
Do you HAVE to increase the mechanical compression ratio before you install a turbo charger? NO! Keep it the same or even decrease it a little if you want. Remember, the higher your mechanical compression ratio, the more stress is placed on the internal engine parts when a turbo is installed. Changing (decreasing) the mechanical compression ratio will require either installing a new head with larger combustion chambers or installing new pistons with concave dishes in the top or decreased deck height. Either way, decreasing or changing the mechanical compression ratio will require significant engine work.
I have not heard of anyone installing a turbo charger on a slant 6 before, but I am sure it has been done. Do research with after market turbo manufacturers to find the right set up for you.
cobraprince
08-06-2008, 11:37 PM
Thank you so much for you help. But I have one last question. Would decreaseing the engines compression help a lot in horsepower, engine life, or both?
KManiac
08-07-2008, 09:33 AM
Lowering the compression ratio will decrease the power output, lower combustion chamber temperatures, put less stress on the components and make it easier to run on regular gas. Raising the compression ratio will increase the power output, raise the combustion chamber temperature, put more stress on the components and require premium fuel.
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