oxhouser

I have the single exit spoon, not sure if it makes any more power but it saves a lot of weight, the OEM is damned heavy. Just to change the subject a little the OEM has a Hemholtz resonater just after the first box do you think thats to remove the drone everyone complains about when running with a CAT? I am tempted to copy the OEM resonator and weld one on the Spoon

MB

Dont weld anything onto the Spoon!

Its been designed with optimum flows in mind and not to be meddled with IMO.

I assume you got a decat? This makes a big difference.

MB

Mattyboyz

I like the thought of having both. But I dont really want to attract silly amounts of attention. Just more

oxhouser

At the moment it's running with decat but I will fit a freflow cat as soon as the group buy happens. I know you know what you are talking about from other post you contribute to but was wondering how a pipe welded at right agles to the main pipe with no reduction in cross sectional area could effect performance.

MB

You would have to ask Ant (SSEL) about it, but not sure it will be that easy - and will be expensive. To cut out the main pipe, and weld on a new one will not be too easy, but I would be more concerned about what it would do to the flow...

Is it just too loud or just at certain rpm?

MB

oxhouser

Its loud but I can live with that (not sure if next door can) but I will fit a CAT in the next month and have heard lots of complaints on drone etc
I know Hemholts is used to tune out certain frequencies depending on size and shape.
It would only mean drilling a 20mm hole in the pipe and welding on a 20mm dia by 160mm long tube at right angles to the main pipe, I can do this at home no problem as I have all the kit to do it.
Only problem is do I mess with the Spoon exhaust and decrease it's re sale value
I f I knew it would help I would do it.

mikey k

must get that one out the garage and onto to car

@Oxhouser - welding the OEM resonator on to the Spoon won't work!
The resonator length, diameter and location are designed to cancel out specific noise frequencies on the OEM zorst. Putting it on the Spoon will not have the same effect. It could well have the opposite of amplifying some frequencies.
The resonator design may look simple but it is a complicated calcuation involving a wide frequency range across all engine revs. Many after market manufacturers don't bother! (Invidia )

MB

Yep, calculating natural and resonant frequencies, and effecting changes is a science in itself!

Some of the tiny things that are done on gas turbines to alter natural frequency excitations are beyond me! A tiny weld here or there can do it.

In this case im not sure what you can do - its a pipe that is always going to be extremely loud. You may find a manifold helps, but it may not!

MB

m1bjr

And its HELMHOLTZ btw

Taikyu

The Spoon dual will be here very soon