Quote:Makes you wonder, why Suzuki even designed the exhaust port that way. The must be a reason for that restriction.
most automotive companies don't port thier heads.. the odd shapes inside and around cast cylinder heads are mostly due to the casting process and how they have to make the molds. Also some of those odd shapes are there for extra structural support to prevent cracking.
In order to get smooth intake and exhaust ports it would need machining which is an extra expencive step in production.. so cost is the main reason why ports are not polished and smooth..
You do lose a little low end power when you increase exhaust flow.. if you equally increase intake flow you should keep your low end power though.. the reason is compression.. at low RPMs there isn't enough momentum in the air charge to pull it in especially with a longer intake duration(as seen in performance cams).. when you have a restricted exhaust some of the gas is not eliminated on the exhaust stroke and stays in the cylinder.. but that's ok because you can't get the air into the cylinder fast enough anyways.. but the extra gas contributes to higher compression which gives you more low end power.
at higher RPMs the air actually forces itself in by momentum even after the piston is done sucking it in.. This allows you to get more air/fuel and more power.
the power you get in your engine is a direct result of the pressure caused by fuel combustion. In a case where the air/fuel is less than optimal as in low rpms having extra gas in there increases the pressure also increasing power..
Porting and polishing are usually just to get that last bit of power you can't get any other way.. It's also free if you do it yourself, but very labor intensive(expensive if you have someone else do it).. a new exhaust or a free flowing air filter will give more power, but if you've already done all of the above you might get a few extra pony's from it..
almost everything to improve performance is done to increase air(oxygen) in the combustion chamber.. then as a secondary thought of course you can easily increase fuel to match the air..
That would be nice if that worked but it doesn't,You lose low end torque,If it worked you would only need one size engine you just put on big carb big ports,big exhaust and you have the power you wanted,Being you lose low end power you have to go to a bigger engine to get more low and high end power.
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