Counter rotating

[Taz]

How do you run twin outboards ive heard of couter rotating engines but how does it work does the gearbox run in reverse?. I wanted to try putting 2x 275 merc on my phantom can i run one engine in reverse? or do i change one prop to compensate?

Cheers for any info

 

[Jon Fuller]

You can't just run a standard box in reverse, you need a dedicated left hand rotation lower unit. sinse about '90 a shiftable left hander (with full FWD-N-RVS) has been available, before that, bespoke, locked in gear left hand boxes were custom built purely for racing with twins, but I would think most are in museums now.

 

[Taz]

So can i convert the box lower unit? Or buy a lower unit?

thanks johnson

 

[Taz]

Yeah the boxes are massive compared to the xr2, Looks like ill be selling the second engine doh!!!!!!

 

[Taz]

Matt you got any links to those boxes?

cheers

 

[Burty]

what would happen if you had both props turnigng the same way?

 

[Burty]

but why?
if you can hold on to 1 engine why not 2?

 

[Louise]

Increased torque???

 

[Taz]

Any one know if a bridgeport box and mid would fit a 275?

 

[Taz]

cheers for the links matt see spares are cheap and a plenty,

 

[Taz]

The bridgeport box is tiny compared to the 275 s, might have to invest in a nose cone maybe that would help.

 

[Jon Fuller]

Stopping 'blow out' is exactly what the various nose cones are for

 

[Taz]

Do you know where i can get one from ?

 

[Jon Fuller]

http://www.bobsmachine.com/


Do a search on this site for 'nose cone'

 

[Captain Chaos]

if you want to avoid agro.....I think bobs will do all the work for you.

I.e....i'd buy the c/r box and have it sent to bobs for them to fit the cone & L/w pickup. Then get them to send the cone kit for the standard rot unit you already got & you'll have one to measure up to & copy.

then all you need is a phantom 23 to stick'm both on

 

[Taz]

Would be nice although i still have the prob i have 25" mids and not 20" unless i got a jack plate for each.

Is bobs any good? You bought nething from there?

 

[Captain Chaos]

I have not bought anything.....but I do have a bobs manual lifter (6inch setback).

if ya doing twins.......wouldnnt you better of with a gill bracket.......custom welded up or sommin??

I'm the wrong fella to be asking about that.........but cant help to think a P20 is way tooo small for all this!

Bobs.....is a well known company....id buy with confidence

 

[Taz]

Ill leave one engine on the p20 for know for fun until a bigger boat comes along. Dont wanna sell your lifter do ya?, sent bob email will order some goodies next week

 

[Taz]

? Matt

 

[Jon Fuller]

I reckon if you put twin 275's on a bracket, on a P20, you'd have massive boyancy problems, even twin 300's on brackets on a P28 look arse heavy, and thats a way longer, and wider boat