1397 cams

[jumjum01]

In 2 days I will recieve my 1397 big bore kit for gen1, motor is taken apart, ready to put new parts on.
I am torn between using stock cams or stock intake and aftermarket exhaust cam with bigger lift.
I would like big low end power, but also like to gain mid/top end without sacrificing the too much low end...
Any of you have experience with 1397 + bigger ex cam? Lobe centers?
Static compression will be between 12.5 - 13:1

 

[michael parris heuberger]

In 2 days I will recieve my 1397 big bore kit for gen1, motor is taken apart, ready to put new parts on.
I am torn between using stock cams or stock intake and aftermarket exhaust cam with bigger lift.
I would like big low end power, but also like to gain mid/top end without sacrificing the too much low end...
Any of you have experience with 1397 + bigger ex cam? Lobe centers?
Static compression will be between 12.5 - 13:1

HI. I have spent my hole life trying to power out of the lower end of the power curve. I find it just makes for to much wheel spin in 1st gear and 2nd. How would like a bike that could spin the tire at 260+ MPH. The guy wo is helping me with my bike had a bike that did that.

 

[busakiller]

More static compression will boost low end power and over all power. Cam degreeing will also help boost power on how you degree them. Bigger cams will help but head porting will help too. Just going to a 1397 will boost low end power.

 

[greg3852]

I would stay away from 395/378 which is what everyone usually recommends. I've read it doesnt like them that big. I had them on my 1397 and think it could have made more power with different ones.

Make sure you have head studs in that kit, or you'll be buying them and a new head gasket in a week or so. And as Busakiller said, you need head work without a doubt.

 

[jumjum01]

1397cc build is now complete. I went with 12.8:1 static compression, stock head (mild cleanup), stock intake cam, aftermarket ex cam (8.64mm lift@240). Bike made 190.42rwhp with big gains from 5k rpm up. Below 5k same as stock. I was hoping for power gains below 5k rpm, so mabye stock ex cam will go back in to bike and see what happens...

 

[busakiller]

1397cc build is now complete. I went with 12.8:1 static compression, stock head (mild cleanup), stock intake cam, aftermarket ex cam (8.64mm lift@240). Bike made 190.42rwhp with big gains from 5k rpm up. Below 5k same as stock. I was hoping for power gains below 5k rpm, so mabye stock ex cam will go back in to bike and see what happens...

You don’t need to gain anything below 5k. Your never in that rpm range. You can change the cam but I doubt you gain anything noticeable.

 

[busakiller]

Let’s see the dyno sheet

 

[jumjum01]

Cam timing is 102/106

 

[jumjum01]

Did a test with stock ex cam today. No big noticeable difference with dyno butt.

 

[jumjum01]

No autotune for gen1 hayabusa, so manual AFR tuning. Made a MS0/MS1 fuel map switch, which added 5% fuel (red graph). From 6500 rpm afr is pretty good on blue map (generic map +7.7%)

 

[busakiller]

I take is what you need. You need to get more air in. Not just out. But hp numbers are impressive for what you havw