[MPac]

Curious to get an opinion. This is a drag racing application, so peak power is most important. My bike is a Gen 5, I’ve still got parts off my gen 4, so I had an idea. I know I’m not doing anything that hasn’t been done, I know it would bolt up but here’s my situation that I’m in.

Currently I’ve got a Brock’s 3/4 alien head on my gen 5. But I’ve also got my full muzzy megaphone system from the gen 4, I was thinking if I would potentially pick up power swapping the muzzy on, like I said it was a full system, I would “think” I would over the slip on.

But something I was looking at last year when I put the alien head on last year I grabbed the can for the muzzy and put it up to the gen 5 header, I’ve noticed the muzzy was slightly smaller diameter then the gen 5 header, which to me logically thinking would pick up torque but kill peak a little bit, atleast in the car world it would. I’ve got a PC5 so I can correct any fueling changes required.

I’m wondering if there is et to be gained doing the swap, thoughts?

 

[ddipaola]

Brock admitted (on his GSXR build) that the Suzuki engineers did a really good job with the OEM headers. Not sure if that can carry across to other manufactures but... It's been word of mouth that on these modern day bikes you can make just as much power on a slip-on (cat-delete) than you can with a full. Schnitz Racing works with the Gen5s quite a bit and they push 195 with a slip-on, stock filter, and their flash-tune. I personally doubt you'll make any more "power" on your current 3/4 system with headers.

As to which system would work better? I know Brock drags with his alien heads and he has sponsored land speed record holders with them so I could almost bet they're pretty damn irreplaceable for getting from zero to stupid-fast!

 

[MPac]

I definitely love my alien head! Yeah I don’t know how it is across the board on oem headers. I do know my gen 4 put down a true 199 to the wheel and 16/43 gearing I’ve gone basement 9’s at 150. So I don’t think I’m putting down 195 with it best pass I’ve gotten out of the gen 5 with gearing at 16/43 is 9.62 at 143. I don’t like the ratio of the gen 5 tranny. Brock’s is local to me within 20 minutes but I really need to get a wide band on it and get the fuel dialed in. It’s got his street map on the PC5 but I almost wonder where it feels like it noses over it may want a little fuel up top.

 

[ddipaola]

I definitely love my alien head! Yeah I don’t know how it is across the board on oem headers. I do know my gen 4 put down a true 199 to the wheel and 16/43 gearing I’ve gone basement 9’s at 150. So I don’t think I’m putting down 195 with it best pass I’ve gotten out of the gen 5 with gearing at 16/43 is 9.62 at 143. I don’t like the ratio of the gen 5 tranny. Brock’s is local to me within 20 minutes but I really need to get a wide band on it and get the fuel dialed in. It’s got his street map on the PC5 but I almost wonder where it feels like it noses over it may want a little fuel up top.

These bikes definitely like to run rich up top, so your intuition is correct haha. Don Guhl's guys run their bikes richer (at high speeds) past like 12K for better street performance. They said it'll make power on the dyno but it will just bog on the road with all that airflow that really can't be replicated unless you're blasting air in. Guhl has worked with Brocks so he'll probably be able to hook you up. My tune (for 200 on pump 93) is running the following:

• Stock Gearing
• A/F = 14 @ 0-7000
• A/F = 13.25/13.5 @ 7000 -11,000
• A/F = 12.75/13 @ 11,000+

Also I was just checking out this page a minute ago. Might be of some use if you've got heavy pockets and are really into racing.
https://parkitt-performance-motorcy...smissions-kawasaki-zx10r-2011-current-gearbox I don't know what my A/F is for E85 and MR12 though, which would make more power. Are you just running pump @ the strip?

 

[MPac]

I definitely love my alien head! Yeah I don’t know how it is across the board on oem headers. I do know my gen 4 put down a true 199 to the wheel and 16/43 gearing I’ve gone basement 9’s at 150. So I don’t think I’m putting down 195 with it best pass I’ve gotten out of the gen 5 with gearing at 16/43 is 9.62 at 143. I don’t like the ratio of the gen 5 tranny. Brock’s is local to me within 20 minutes but I really need to get a wide band on it and get the fuel dialed in. It’s got his street map on the PC5 but I almost wonder where it feels like it noses over it may want a little fuel up top.

These bikes definitely like to run rich up top, so your intuition is correct haha. Don Guhl's guys run their bikes richer (at high speeds) past like 12K for better street performance. They said it'll make power on the dyno but it will just bog on the road with all that airflow that really can't be replicated unless you're blasting air in. Guhl has worked with Brocks so he'll probably be able to hook you up. My tune (for 200 on pump 93) is running the following:

• Stock Gearing
• A/F = 14 @ 0-7000
• A/F = 13.25/13.5 @ 7000 -11,000
• A/F = 12.75/13 @ 11,000+

Also I was just checking out this page a minute ago. Might be of some use if you've got heavy pockets and are really into racing.
https://parkitt-performance-motorcy...smissions-kawasaki-zx10r-2011-current-gearbox

Killer man! Thanks!!!