Best pipe lenght for SG Rigger 45

[Richard Mancilla]

Hi Guy's,

Any help will be greatly apreciated.

SG 45

Newer Mac 45

Andy's Parabolic pipe

1457/2 prop

Thanks,

Richard

 

[Tom v.d Brink]

richard,

you can start at 9,5" but that is very much a safe setting

the engine will take shorter lengths but just start working your way inwards

then you should end up at something you feel comfortable racing with

good luck

 

[RIGGERMORTISE]

All my 45 riggers and monos run at 250mm from the plug to the widest point on the pipe. All are fitted with Carbon fibre tuned pipes. happy to answer any questions regarding the carbon pipes but not here to avoid congestion. Email [email protected]

 

[AndyBrown]

For racing I set mine at 9.5" at leave it there. Then just work with the prop according to availible power. Should be easy to pull the 1457 under normal conditions.

About the newest MAC 45; The stock head clearence is about .012"-.013" with the supplied .008" shim. The best performance will be had with the head set at .008".

Just replace the .008" shim with a .004".

In the near future we will have .002" and .003" shims availible for the MAC 45 This will allow you to really hone in on the best head clearence.

 

[Dan_Cousin]

Where are you measuring from for the pipe measurement?

Plug to max diameter?

CL of engine to max diameter along center of the pipe?

 

[Richard Mancilla]

Hi Andy,

Can you tell me where you measure the pipe? I normally measure from the plug to the weld. I have the pipe set for 10" now.

Thank you all for your reply..........

Richard

 

[Don Ferrette]

"CL of engine to max diameter along center of the pipe?"

This how you want to measure the pipe. Reason being if you use headers with a different angle (like a 10 degree vs. 18 degree) you can have inconsistency in your measurements going from plug to weld (or max diameter). When testing pipes I like to set them up with headers ready to go & sometimes you use what's handy even if the header angle isn't what you will use in the end, it just lets you test quicker. B)

 

[Lay26]

the plug to weld measurement can yeild about a 1/4" difference than if you measure center of motor to weld

 

[John Knight]

I know both Andy and John well. They measure from the middle of the crankcase to the weld on the pipe. I asked John at the Atlanta race in April and that was what he said.

 

[Dan_Cousin]

Thanks guys,

THe other way I've heard to measure is to measure from the Face of the piston in the exhaust port, to middle of the convergent cone (half way between max diameter and the stinger). This will make the tuned length more consistant between different pipes.