ZCar Forum banner
Status
Not open for further replies.
1 - 4 of 4 Posts

· Registered
Joined
·
1,351 Posts
Discussion Starter · #1 ·
I have a 78 Zed. I had some difficulty imaging how a hi=-perf cam would work. From what I know itholds the valves open a little loinger than witht he stock cam, as the lobes are bigger, or "lumpy". So, is it true that the engine sucks more air throught the intake valves, thus the AFM senses it and sends a tronger signal to the ECU, which increases the duration of the injection pulse... is it something like that, or am I missing something..
 

· Registered
Joined
·
2,676 Posts
on the right track...

There are lots of ways to make a cam "hotter" Usually the profile of the cam lobe is altered, it is actually made smaller not bigger as a lot of people think. The fat end of the lobe can be turned down so that when the lobe pushes down on the rocker arm it pushes it farther which opens the valve further. The gap left from the removed part of the lobe is usually taken up by thicker lash pads as to not upset the geometry of the valve train. Also the shape of the lobe can be varied to open the valve faster, and keep it open longer depending on the type of grind that is done to it.
 

· Registered
Joined
·
3,207 Posts
Re: on the right track...

Hi John.
Without meaning to ignore your orignal question I want to state that the best aftermarket Cam is actually the stock cam of the later 260. Its 'duration and lift' are ideal for higher reving engines....5500 to 8300 rpm. later. shane-
 

· Registered
Joined
·
567 Posts
Re: on the right track...

Huh? The 260 cam was same lift with not enough extra duration to make any measureable difference. Far from a 8300 rpm cam.
May be the best "junkyard" cam....
 
1 - 4 of 4 Posts
Status
Not open for further replies.
Top