Heads and cam
Thread Starter
Melting Slicks
Joined: Nov 2002
Posts: 2,471
Likes: 2
From: 1993 Quasar Blue 'vert Scottsdale AZ
Heads and cam
First of all, the stupid question of the day. What does CNC stand for? My heads are being CNC ported and I realized that I don't or can't remember what that stands for. Also, I'm having a new cam installed. I told the shop to use a Hotcam unless they had something different that was similar but better (emissions friendly). They discussed it and since my car is a '93 (speed density), the Hotcam is the best way to go. You all agree?
Le Mans Master
Joined: Jan 2003
Posts: 8,596
Likes: 19
From: Portland Oregon
Originally Posted by Lichen
First of all, the stupid question of the day. What does CNC stand for? My heads are being CNC ported and I realized that I don't or can't remember what that stands for. Also, I'm having a new cam installed. I told the shop to use a Hotcam unless they had something different that was similar but better (emissions friendly). They discussed it and since my car is a '93 (speed density), the Hotcam is the best way to go. You all agree?
Basically it means that the milling machine that is doing the work on your heads is controlled by a computer that has a program to port your heads.
A HOT CAM is a good choice, it works well in most mild performance applications and is a proven package when matched with the proper springs. You will still require a custom chip in the ECM to get the full benefits from your cam and head package.
Race Director
Joined: May 2001
Posts: 14,165
Likes: 9
You will need a custom computer program to get the most out of your mods but you will be very happy with the Hot Cam. There are certainly more powerful cams out there but if emissions are a concern you can't go wrong with it. I don't know of any better cam for power AND emissions than the LT4 Hot Cam. GM designed that cam specifically for that engine and they have a lot more R&D budget than most places do I imagine. It's not the ultimate, but it is damned good for a wider range of applications that most cams are.
As for the heads, people will argue the merits of CNC vs hand porting from now until eternity. Personally I believe in CNC. If you really know what you are doing you can hand port a head better than a CNC, BUT there is the problem. You can also REALLY dick up a set of heads in a heartbeat. A CNC machine is used to basically copy a good hand port job and the results are nearly 100% consistent. It saves a lot of time and it takes a lot of the guess work out of the job. FYI most heads that are CNC'd have some finish hand porting done, the CNC just does the bulk of the work without the fear of the "Bubba" factor. However a bad finish job can dick up a set of CNC'd heads pretty quickly too!
As for the heads, people will argue the merits of CNC vs hand porting from now until eternity. Personally I believe in CNC. If you really know what you are doing you can hand port a head better than a CNC, BUT there is the problem. You can also REALLY dick up a set of heads in a heartbeat. A CNC machine is used to basically copy a good hand port job and the results are nearly 100% consistent. It saves a lot of time and it takes a lot of the guess work out of the job. FYI most heads that are CNC'd have some finish hand porting done, the CNC just does the bulk of the work without the fear of the "Bubba" factor. However a bad finish job can dick up a set of CNC'd heads pretty quickly too!
