3.5 outboards aussi

[David Kingston]

QUEENSLANDER !!!!!!!!!!!!!!!!!

ROCK ON BOYS....

Just have to stir the pot. been super quiet here. Need that little spark... Might have to paint my latest tunnel maroon and change my race number to 4.............4 in a row actually would be better....

On a serious note. I am looking fwd to the school holiday here, as i might have a a bit of time where i can paint some boats and do some testing. New boats that i really want to water test and get up and going. Will post some pics shortly as well.

Dave

 

[ozbryan]

Dave if you paint it maroon dont bring it to sydney... no refs at our pond that secretly like it up the A@@... it might end up not so water proof LMAO

 

[Kris Flynn]

My tip is for Graeme to be in the points next weekend, Kesso, Louise and myself to have to REALLY good racing and hopefully Kesso has his 3rd channel set up to go the right way by now HAHAHA

 

[poolschool]

My tip is for Graeme to be in the points next weekend, Kesso, Louise and myself to have to REALLY good racing and hopefully Kesso has his 3rd channel set up to go the right way by now HAHAHA

Kesso is a true champion and I'm sure he'll fly the flag for Sydney!!!

 

[ozbryan]

My tip is for Graeme to be in the points next weekend, Kesso, Louise and myself to have to REALLY good racing and hopefully Kesso has his 3rd channel set up to go the right way by now HAHAHA

Dont be to sure about the 3rd channel Kris LMAO

 

[Tim_Duggan]

Happy B'day OzBryan!

 

[sneakysneakyracing]

im having a cmb 100 and a 90 converted for ob use. dose anyone know of a gas tunnel thats made in australia. my only other option is a DPI copy

any help would be good.

btw i'm in bangkok if anyone wants somthing from thong fiber

 

[David Kingston]

Boys in OZ running, or that have run Mac motors, on OBT's what have you been setting the pipe length at as a general starting point.

New toy on the water is going to be great fun. Few more adjustments to it and it will be time to put out there with other boats and see what is able to do.

Dave

 

[Tim_Duggan]

Keep shortening it until it won't get on pipe any more, then lengthen it a bit. It all depends on the prop, fuel and air. all of those can effect the length it runs at. The trick is not to over-prop it, as it will run, but will be sloooooooooooooow.

 

[Kris Flynn]

From what starting length Tim? 8"???

 

[Tim_Duggan]

SPP NR21OB? I'd start at 225mm from plug to start of rear cone and shorten from there..

If it's that pipe, make sure the stinger in the converging cone is 0.290". There is a version with a smaller diameter also - which I just couldn't get right on the MAC. Didn't like the backpressure. Works great on a novarossi though!

 

[Kris Flynn]

there are no visible markings on the pipe, it is also the newer rougher carbon from the pipe I bought from you ages ago (NR21OB that is)

 

[Tim_Duggan]

Put a 0.290" drill bit in thru the muffler outlet into the pipe stinger. If it goes in - all good. If it doesn't it's probably a 0.270". Should be OK to drill out but do so at own risk!

 

[David Kingston]

Tim will test the drill bit in the stinger before i get to really test it...

For now, starting pipe length at 8inch and see what happens... Got to run it in first, so here come some old fuel burn time. Will put a couple of tanks of that through it before i put my fresh 50 or 60% in there...

Are people still running the standard Mac Carb on the OB motor also. Ive got a CMB cab that i might try on there. With low end settings on it.

Dave K

 

[David Kingston]

what plug also have people found works best?

DK

 

[Tim_Duggan]

On mine I ran K&B 1L's on 50%. The low end carb helped a lot on mine. It fueled up a bit without it. Bryan is using the OS carb that comes on the OS outboard on his MAC and it seems to work well also.

 

[kesso2118]

Dave,

Be careful starting at 8" (203mm). To start at that length means you might cut the header or pipe a bit short??

I used to run the SPP NR21OB pipe at about 220 - 225mm on my HTB/MAC with the CMB RS carb with Low End needle and K&B 1L plugs.

Good Luck,

James

 

[David Kingston]

Thanks boys...

I will test with both carbs on the water when i can.

Will just run a MC9 for now...

Dave

 

[Tim_Duggan]

You'll get better carb testing results with the hotter plug. If you must use Mccoy's try MC59's.

 

[HOOTERS Racing]

the MC59s is what i use and i love them