I'll throw out my .02 -
Jerry makes a good point of talking to the cam manufacturers - ask the specifically what cam for your riding style and the desired end result. These need ot be very clear in the conversation. After you have the discussions and get the info, take a moment of pause and ask yourself "are you sure your never wanting to do headwork". I say this from experience because "power is addictive". Having ridden almost everything from a dirt bike to streetbikes to F1 unlimited roadracers, it's lots of fun to have usable power - the grin factor goes up exponentially.
When it comes down to it - headwork is probably the most single performance expensive item. Minor cleanup and decking will usually be $300 to $500 and you can run the gamut to billet heads and lots of work - only limited by the depth of your checkbook.
There are several types of headwork that can be considered. I used to work for a guy that jokingly called them "cleanin it up", "it's gonna breathe" and "hand me the big grinder". The minor clean up consisted of checking the chambers for proper cc size for the build and decking, a little cleanup on matching ports and making sure the valves / guides were in spec. The second phase usually involved cc'ing the heads, going with bigger valves, better guides and springs, port and runner shping, and flow testing to make sure things were identical. The third phase was usually the most intense: changing valve all of the other stuff, but a lot more, and changing valve angles, straightening runners and doing the complementary work in the intake to match the headwork. Needless to say, very few opted for the last choice - nothing like taking a set of $1000 heads and turning them into $5000 heads - especially if the heads get damaged if the engines blows and the new $5k heads are now good coffee table stands.
The only reason I mention this is - whatever the cam manufacture tells you is a guide, not a guarantee. There are variances in echaust choice, air filter / housing choices and especially in the tuner. The manufactur should be able to tell you cam x shold give you around this HP / tq and with minor head work (the cleanin it up) should get you this. He should also be able to tell what type of exhaust the used in the testing 2 into 1, stock head pipes and slip-ons, etc. This makes a noticable difference in the final outcome.
Had this same discussion with a couple of buds a few years ago - we thought about setting up a shop that offered these type of choices. We found two severe limitations - first, people did not want to hear their new Brand X drag pipes they paid $600 for were killing thier bottom end and they needed something else. The second limitation was a tuner that new more than what the initials of SERT stood for. Still looking for a SERT tuner in TX or even the 5 state area that knows what is going on other than creating a "three pass canned map".
Not trying to influence, just adding comments on past and current experiences.
As the sign on the wall of the local speed shop read "Speed is a question of money - how much do you have? That ain't enough"
Jim
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Topic: ADDITIONAL TWEAKING? (Read 1691 times)