question for 82 owners
Thread Starter
Instructor
Joined: Nov 1999
Posts: 147
Likes: 0
From: Portland, Oregon
question for 82 owners
The inside of the runners were rough sand casted
and have very large peeks caused by casting seams that cuts
the flow down to around 125 CFM of just matching the valves
and cam.
What is 125 CFM? and what does CFM stand for?
and have very large peeks caused by casting seams that cuts
the flow down to around 125 CFM of just matching the valves
and cam.
What is 125 CFM? and what does CFM stand for?
Le Mans Master
Joined: Apr 2001
Posts: 5,000
Likes: 1
From: Minneapolis, Mn USA
Re: question for 82 owners (Chas 95)
The 82 L83 intake manifold is cast with ports that are extremely small. This help with flow velocity at lower RPMs and is what gives the engine it 285 ft lbs of torque rating at 2800rpm but is what also part of what keeps HP low at 200 HP at 4000rpm.
CFM is Cubic Feet per Minute
There is an X-Ram manifold on the market that has larger ports and reportedly gives a horsepower increase. I think the twin throttle bodies only allow like 550 CFM flow so in order to feel the manifold increase, you need to bore the throttle bodies, upgrade the cam, and probably enlarge the exhaust side with a set of headers too.
Really it is all just basic engine hop up theory applied to fuel injection principles. Elementary
Someday Ill probably go TPI or the Holly/Edelbrock FI route.
Brent...
[Modified by MN-Brent, 12:50 PM 11/28/2003]
CFM is Cubic Feet per Minute
There is an X-Ram manifold on the market that has larger ports and reportedly gives a horsepower increase. I think the twin throttle bodies only allow like 550 CFM flow so in order to feel the manifold increase, you need to bore the throttle bodies, upgrade the cam, and probably enlarge the exhaust side with a set of headers too.
Really it is all just basic engine hop up theory applied to fuel injection principles. Elementary
Someday Ill probably go TPI or the Holly/Edelbrock FI route.
Brent...
[Modified by MN-Brent, 12:50 PM 11/28/2003]
Advanced
Joined: Nov 2001
Posts: 81
Likes: 0
From: Bay Minette ALabama
Re: question for 82 owners (MN-Brent)
Or you can port match the intake to the head yourself with a die grinder and smooth out all the casting imperfections. This is what I did and made a nice performance increase. Also you can modify the swirl plates to increase airflow from the TB's. The only cost to you would be your time doing it compared to the 400.00 cost of the X-ram.
Just my .02
Ed
Just my .02
Ed
Race Director
Joined: Jun 2001
Posts: 16,483
Likes: 1
From: The Only Corvette in Gila Bend, Az.
St. Jude Donor '09
Re: question for 82 owners (Eds82)
There's tons of great info, and people at the Crossfire web site.
http://www.crossfire.homeip.net:81/
Join up and jump right in..... :seeya
http://www.crossfire.homeip.net:81/
Join up and jump right in..... :seeya
