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Pre 98 600:
Yoshi header (nitros222)
Notes:
Mod needed to belly pan.
98+ Yoshi 750
Notes:
Same as above
98+ Stock 600 exhaust
Notes:
Mod required to clear oil pan. (dent collector or use 98+ pan)
98+ Stock 750 exhaust (waltri/ Cyber poet)
Notes:
Mod required to clear oil pan. (dent collector or use 98+ pan)
Pre 98 750:
98+ exhaust (a few incuding CP)
Notes:
Same as for 600 install above
98+ 600:
Bandit 600 header (beekman)
Notes:
Center stand needs removing.
Trim belly pan
98+ 750:
Bandit 1200
(results to follow.. inprogress)
1100:
86-89 ZX-7 Muzzy full System.
Notes:
Outside pipes require a little spreading (3/8")
Can matches stock mounts.
Pre 92 GSXR header
Formula: (Cyber Poet)
For the mathamaticly bold:
Example (values not absolute, just plucked out of the air):
Stock 98+ Kat 600 header: 23mm diameter
Stock 98+ Kat 750 header: 26mm diameter.
Area = Pi (radius^2)
Radius = 1/2 diameter
Thus
Area = Pi ((.5 (diameter))^2)
For the 600, the formula would go like this:
Area (square mm) = 3.14 * (1/2 * 23)^2
Area = 3.14 * (11.5)^2
Area = 3.14 * 123.25
Area = 415 square millimeters
For the 750 exhaust by comparison:
Area (square mm) = 3.14 * (1/2 * 26)^2
Area = 3.14 * (13)^2
Area = 3.14 * 169
Area = 530.6 square millimeters
One more formula to compare the two cross-sections (and therefore the flow rates):
((new/old)-1) * 100 = percent change
((530/415) -1) * 100 = % change
((1.277)-1) * 100 = % change
.277 * 100 = % change
27.7% change
(For those of you who want to jump my case about subtracting one and multiplying by 100 as incorrect math -- I simplified the whole percentage thing down [KISS] for those poor at math).
Thus, the 750 header flows 27.7% more than the 600 header. That's a substancial difference, enough to warrant serious jetting changes under most circumstances. A jump to an 1100 exhaust may induce an even bigger change, one that will take a lot of experimentation to come up with the right jetting for...
On the other hand, simply grinding out the welding seam lip on the same 600 header will net you a couple more mm of clearance on the exhaust, giving you about a 15 - 20% flow change for the cost of a couple dremel grinding accessories (provided you already have the dremel or equivilent).
ONE BIG NOTE:
Back pressure at low RPM's causes the engine to produce substancially more torque; this same back pressure at higher RPM's works against the engine's ability to flow large quantities of exhaust. Thus, it's a trade-off, and depends on where you want to make the power. For a more detailed discussion of back-pressure and how it affects torque/hp/power, see this thread: http://www.katriders.com/forums/viewtopic.php?t=2400
Yoshi header (nitros222)
Notes:
Mod needed to belly pan.
98+ Yoshi 750
Notes:
Same as above
98+ Stock 600 exhaust
Notes:
Mod required to clear oil pan. (dent collector or use 98+ pan)
98+ Stock 750 exhaust (waltri/ Cyber poet)
Notes:
Mod required to clear oil pan. (dent collector or use 98+ pan)
Pre 98 750:
98+ exhaust (a few incuding CP)
Notes:
Same as for 600 install above
98+ 600:
Bandit 600 header (beekman)
Notes:
Center stand needs removing.
Trim belly pan
98+ 750:
Bandit 1200
(results to follow.. inprogress)
1100:
86-89 ZX-7 Muzzy full System.
Notes:
Outside pipes require a little spreading (3/8")
Can matches stock mounts.
Pre 92 GSXR header
Formula: (Cyber Poet)
For the mathamaticly bold:
Example (values not absolute, just plucked out of the air):
Stock 98+ Kat 600 header: 23mm diameter
Stock 98+ Kat 750 header: 26mm diameter.
Area = Pi (radius^2)
Radius = 1/2 diameter
Thus
Area = Pi ((.5 (diameter))^2)
For the 600, the formula would go like this:
Area (square mm) = 3.14 * (1/2 * 23)^2
Area = 3.14 * (11.5)^2
Area = 3.14 * 123.25
Area = 415 square millimeters
For the 750 exhaust by comparison:
Area (square mm) = 3.14 * (1/2 * 26)^2
Area = 3.14 * (13)^2
Area = 3.14 * 169
Area = 530.6 square millimeters
One more formula to compare the two cross-sections (and therefore the flow rates):
((new/old)-1) * 100 = percent change
((530/415) -1) * 100 = % change
((1.277)-1) * 100 = % change
.277 * 100 = % change
27.7% change
(For those of you who want to jump my case about subtracting one and multiplying by 100 as incorrect math -- I simplified the whole percentage thing down [KISS] for those poor at math).
Thus, the 750 header flows 27.7% more than the 600 header. That's a substancial difference, enough to warrant serious jetting changes under most circumstances. A jump to an 1100 exhaust may induce an even bigger change, one that will take a lot of experimentation to come up with the right jetting for...
On the other hand, simply grinding out the welding seam lip on the same 600 header will net you a couple more mm of clearance on the exhaust, giving you about a 15 - 20% flow change for the cost of a couple dremel grinding accessories (provided you already have the dremel or equivilent).
ONE BIG NOTE:
Back pressure at low RPM's causes the engine to produce substancially more torque; this same back pressure at higher RPM's works against the engine's ability to flow large quantities of exhaust. Thus, it's a trade-off, and depends on where you want to make the power. For a more detailed discussion of back-pressure and how it affects torque/hp/power, see this thread: http://www.katriders.com/forums/viewtopic.php?t=2400
Good judgement comes from experience, and often experience comes from Bad Judgement :smt084
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