|
CrazyAl -> RE: COMPCAM STAGE 3 (1/20/2007 11:20:30 AM)
|
Have a chat with some of the guys who have done the engine building and run the dynos: JDM, Livernois, Fox Lake, etc. All of them will report that if you're doing heads adding the cams is a minor upgrade (if that) at that point. One of my local Mustang buddies (I did his suspension work) is buying a forged motor from JDM. His plan is to put a blower on it a a couple of years down the road, but right now he wants to run N/A. JDM told him that they ONLY use the stock cams with their heads becasue there is no noticeable HP advantage to use aftermarket cams. He was ready to buy everything from them, and they actually talked him out of spending the extra money for the cams. The issue is that a good set of ported heads flows so well (even with the stock cams), that cylinder filling is a non-issue on the 4.6 motor. There's just no need for the extra flow. Now then, if you use a cheaper set of heads that dones't have the oversized valves or if you have a motor that's stroked or bored so you have more displacement, then the cams + heads might be a better deal, but I don't have any experience with that particular combination. I agree that if you were already doing heads you could add the aftermarket cams for a modest (relatively) cost. But I would argue that unless you had big plans for the motor later on, that is not a particularly wise plan. Doing just cams on your stock heads will give you 80% of the HP gain of the heads for a lot less money. For example, we know you can do heads, cams, and springs installed for about $2000. That's worth about 35-40 HP given that you already have the supporting mods--which you'd better have for the heads too. If we assume max HP, that's $2000 for 40 HP, or $50 per HP. Now in the case of Heads, the various mag reviews are putting the gain at about 40-50 HP for the heads with the oversize valves. These cost about $2500-3000 depending on where you get them from. Even if you stick with the stock valvetrain parts (Cams & springs), you're still looking at another $300 or so for gaskets, head bolts (they are TTY), and other misc. parts. Then, your install is going to be $1500 or more. That's putting us about $4500 (or more) for 50 HP...or $90 per HP. If you do both, your labor cost will be essentially the same as doing just the heads, but you're throwing on an extra $1000 or so for the cams and the valvesprings. JDM and Livernois both claim no gain with heads and cams but if we assume they're wrong and figure you get an extra 15 HP, then you're still looking at $5500 for 65 HP...or $84 per HP You see why I'm suggesting either cams only or forget the whole deal? By the time you're looking at both cams and heads you are in supercharger territory! In that case for a similar amount of money you could have a lot more HP potential. Personally, I think the cams are a worthwhile deal. If you do your own labor the deal becomes even better! The only reason why I haven't done them yet is becasue I will be going the supercharger route later this year. Agressive cams like the Stage 3s do not work well with FI.
|
|
|
|