What is the CFM
Thread Starter
Instructor
Joined: Apr 2008
Posts: 240
Likes: 0
From: Peachtree City GA
What is the CFM
Im building a 406, vortec head with TPI Vortec Baseplate,
The formula Calls for a Single Plane with a Holly 750, I have the 85 c4, What set up in fuel Injection, is equal to that?
IE: mini Ram? Hiflow runners, 36 lb injectors? Does anybody know....
The formula Calls for a Single Plane with a Holly 750, I have the 85 c4, What set up in fuel Injection, is equal to that?
IE: mini Ram? Hiflow runners, 36 lb injectors? Does anybody know....
Racer
Joined: Oct 2007
Posts: 250
Likes: 1
Hello,
The injectors have nothing to do with the CFM.
The CFM is Cubic Feet per Minute of airflow. Check with your throttle-body manufacturer for the cfm of your throttle body (i am assuming you are running a larger than stock throttle body (bigger than 48mm)). You will need to check with the manufacturer of you plenum, runners and base to get s cfm estimate.
Your best bet is to take your Intake, runners, plenum, throttle-body and Mass Airflow Sensor (if equipped) to a engine shop that has a flow bench. The should be able to flow one side at a time and add the two together. Have them also do this without the MAF sensor (because this could be your restriction). These numbers tell you what you have got exactly. You then take your manufacturers specs and look for your 'bottle-neck'. If you are close to what you want to flow, The engine builder may be able to port your current components to get you where you want to be. This MAY be cheaper than buying more runners, plenum, base etc, etc...
I hope this info helps, Take Care, -John
The injectors have nothing to do with the CFM.
The CFM is Cubic Feet per Minute of airflow. Check with your throttle-body manufacturer for the cfm of your throttle body (i am assuming you are running a larger than stock throttle body (bigger than 48mm)). You will need to check with the manufacturer of you plenum, runners and base to get s cfm estimate.
Your best bet is to take your Intake, runners, plenum, throttle-body and Mass Airflow Sensor (if equipped) to a engine shop that has a flow bench. The should be able to flow one side at a time and add the two together. Have them also do this without the MAF sensor (because this could be your restriction). These numbers tell you what you have got exactly. You then take your manufacturers specs and look for your 'bottle-neck'. If you are close to what you want to flow, The engine builder may be able to port your current components to get you where you want to be. This MAY be cheaper than buying more runners, plenum, base etc, etc...
I hope this info helps, Take Care, -John
Thread Starter
Instructor
Joined: Apr 2008
Posts: 240
Likes: 0
From: Peachtree City GA
Thanks John, I have everything Stock ( 85 C4)at this Point, As far as I know, the car does have a 52mm TB, I have no idea what other changes then previous owner might have done.
I have purchased a 400 motor with the intentions of building. As i buy parts for the build, i just dont want to waste money.
I have purchased a 400 motor with the intentions of building. As i buy parts for the build, i just dont want to waste money.
