Kasama Header

[DesertFlyer]

Kasama header for the YS91SR worth the money?

[rcmarty]

I'd like to know why it is better also

Better alignment to the engine exhaust ? (say the stock one had a smaller hole and therefore potentially blocked flow)

Martin :)

[Aberdeen]

Ports are matched.

You can modify the stock header for the YS by using a Dremel.

First mount the header to the motor using black or blue silicone.

Let dry.

Remove header and you can see the imprint of the silicone, the areas you need to grind the Port so it will be matched to the the motor.


Anthony

[Finless]

Bottom line the header is ported to allow the YS to run a little higher head speed. I am not sure grinding the stock header will accomplish the same thing.. Yes it will re-tune the pipe but you wont get the other benefit which is the port is centered and not offset like the stock one. I believe this provides more power as well as the re-tune.

Another benefit is the way the header mounts. The nuts are on the outside and thus easier to service. A friend of mine crashed his Synergy last weekend and damaged the pipe and bent it in a way that he could not get at the screws to remove it. With the reverse bolts on the Kasama you will always be able to get at the nuts with a wrench.

Bob

[DesertFlyer]

Ports are matched.

You can modify the stock header for the YS by using a Dremel.

First mount the header to the motor using black or blue silicone.

Let dry.

Remove header and you can see the imprint of the silicone, the areas you need to grind the Port so it will be matched to the the motor.


Anthony



My header has an opening that exactly matches the the engine exhaust opening. What do you grind off?

[Aberdeen]

My header has an opening that exactly matches the the engine exhaust opening. What do you grind off?

Do you have a YS 91SR and the Hatori SB-19FH ?

[JodyJ]

Here's some pics of the difference between the Kasama vs. stock header:

http://www.helifreak.com/showthread.php?t=81909

Jody J.

[DesertFlyer]

Do you have a YS 91SR and the Hatori SB-19FH ?

Deleted

[HeliSmith]

Would be cool to see someone measure the torque of the motor with each header. The bhp right off the motor showing one was better than another.

[Aberdeen]

Deleted

You posted it was a perfect match.
Please post pics..

[rcmarty]

The kasma will flow better no questions asked.
See the pic in the link above.

The centered hole will allow a better flow , the ofset hole will cause turbulance like a toranado and tornados don't like to move.

More hp goes to the kasma header because it will flow better and allow a better evacuation and charge of the motor.

On a side note : anyone know where to get one of these headers in canada ?

Martin :)

[DesertFlyer]

You posted it was a perfect match.
Please post pics..

My Hatori header is definitely different than the one pictured in the post. It has weird knurled backup nuts instead of tapped holes in the header to hold on the pipe. Kind of a bad setup since the knurled nuts could spin if too much lock tite was put on the machine screw or the machine screw over torqued. After looking at the picture, I'm now not so sure the sides of the header opening match up with the sides of the engine exhaust port. I think I'll have to take back my statement. I don't see how it could match up given the position of the opening in the header. Next time I take off my pipe, I look at the header and post back here.

[JodyJ]

DesertFlyer, do you have pics of your Kasama header?

The Kasama header will line up to the engine port with no problems. If you look at the picture, move the stock header to match the kasama mounting holes that connect to the engine and you'll the the ports will match up.

The only thing I had to do with the Kasama header was clearance the fan housing as the header will touch it.

[derelict]

this leads to another question..... why did hatori design THEIR header with THEIR pipe FOR the YS 91 SR so "wrong" with a hole which doesn't match the engine???

marcel

[Aberdeen]

this leads to another question..... why did hatori design THEIR header with THEIR pipe FOR the YS 91 SR so "wrong" with a hole which doesn't match the engine???

marcel

Every pipe I bought of Hatori, the header NEVER matched the engines port.
makes you wonder how the make a "TUNED" pipe for a given engine...:thinking

[derelict]

that's exactly what i'm saying/wondering/asking :-)

[HELINHAWAII]

Well, in their eyes it is "TUNED". In our eyes it's "BADLY".

[Mercuriell]

Matched or not the stock Hatori header and pipe SB18 FH for the OS works superbly and gives me more power than can I use right now :) - I wonder if it's all about laminar flow - the Hatori header hole reminds me of an organ pipe - maybe it's setup to produce a resonant standing wave rather than smoothly port gas out

[Finless]

John... the Kasama headers "retune" the pipe. For 90's the stock header is tuned to around 1800-1900 HS depending on gearing of course... Some guys (like me) are liking a little more HS like 1950 to 2000 and that is what this does.

Bob

[rcmarty]

John... the Kasama headers "retune" the pipe. For 90's the stock header is tuned to around 1800-1900 HS depending on gearing of course... Some guys (like me) are liking a little more HS like 1950 to 2000 and that is what this does.

Bob


True.

Of course you would need better flow to make that happen.

I had a look down the exhaust port and even ys could stand a little port matching. At least there doing a chamfer cut on the sleeve ports.

On a side note :

My sr is says in the book it's for a helicopter with gearing up to 2.0 , the 700 being 8.2

I assume this means it will have to rev out more to get the same headspeed ?

Martin :)