a little more power
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madmike2
Shtirrenuppenmeister
And for the extremely limited amount of increased performance and probably loss of fuel mileage.....? :blink: I'm sure you can find pistons or at least someone who would modify existing pistons to work, but given the cost I wonder if it wouldn't be more financially prudent to begin with a complete exhaust system (headers and slipons) and a PCIII which seems to net some owners 5-10 HP increase.
If you've alrady done the above mods, then why not pursue changing the cams? Though the torque band would likely be more narow you should be able to find an increase in peak HP, perhaps with the change of cams, you would find an exponetial gain across the RPM band, though li9kely at higher RPMs. Increasing the compression ratio by replacing the pistons would likely guarantee using higher octane rated gasoline.
If you've alrady done the above mods, then why not pursue changing the cams? Though the torque band would likely be more narow you should be able to find an increase in peak HP, perhaps with the change of cams, you would find an exponetial gain across the RPM band, though li9kely at higher RPMs. Increasing the compression ratio by replacing the pistons would likely guarantee using higher octane rated gasoline.
ionbeam
2 FUN
Yamaha's Ceramic Composite Cylinder Coating would make resizing pistons a bad idea.
Inability to access the spark timing maps make other positive pressure solutions impractical.
External breathing changes to the intake and exhaust will improve volumetric efficiency, but at the cost of shifting the power band higher, hurting daily drivability.
As far as I know, there are no off the shelf hot cams.
A very light nitrous shot in combination with a PCIII may be possible.
Inability to access the spark timing maps make other positive pressure solutions impractical.
External breathing changes to the intake and exhaust will improve volumetric efficiency, but at the cost of shifting the power band higher, hurting daily drivability.
As far as I know, there are no off the shelf hot cams.
A very light nitrous shot in combination with a PCIII may be possible.
Just contact a company like Diamond, Weisco, Jahns, etc. They will make you a custom piston in any configurtion you want. Not even that expensive.
With the advent of resonably priced, CNC machining centers making custom pistons went from an difficult, expensive black art to something that many shops can do. They all use a series of commercially avialble forged piston blanks and machine from there.
With the advent of resonably priced, CNC machining centers making custom pistons went from an difficult, expensive black art to something that many shops can do. They all use a series of commercially avialble forged piston blanks and machine from there.
