4age head swap, Worth it? Options

[BigJ]

Ok another question i have about fixing up my 7afe is this: I found most the HP internals as far as the bottom end is concerned but what about the top end. I looked into the 4age head swap but that seemed like a bunch of crap. Changing to 4a pistons and all that other mess. The "G" head is toyotas performance head right. Couldnt i just make my "F" head a performance head? I mean whats the real big difference between the heads. Wouldnt it be easier to rebuild the head i have with some performance parts like valve springs and lifters and stuff (if any are availabe for the 7a). Then have bigger cams or have my existing cams shaved and then do a port and polish. Never really worked with heads much so this is not my forte. Lemme know what you guyz think....

This post has been edited by BigJ: Dec 1, 2004 - 4:04 AM

[Dr_Tweak]

the difference between the g head and the f head is the over all design.

the vavles are angled more flat on the g head so the flow is better.  while the f head  has more of a steep angle. think of it this way. the air has to go into the engine and then make a 180 degree turn to come back out on an f head.. where as the g head is like two open doors oposite from each other. the air just passes through both the doors and comes out..   this is a VERY butchered version of what is happens.


so if you add all those parts like valve springs and port and polish to the F head .. the air still has more resistance traveling through the head compared to the G head.


i hope i got the idea right.. someone correct me if i am wrong.
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Yeah you basically got it. The valve angle is a lot different. Not to mention that the cams run off one sprocket so you can't tune them seperately. And the ports are really small... etc etc etc

So the answer is no, you can't really fix up the F head. Get yourself a G head or a complete 4AGE.

This post has been edited by raven_101: Dec 3, 2004 - 2:14 AM