Twin f Hull

[Bob Morton]

Hows about sharing the weight of your twin F hydro hulls

Thanx

Bob Morton B) B)

 

[Mike Hughes]

Just under 16 lbs. Had to break it up on the scale. Max weight of scale is 12lbs. Weighed the motors and pipes separate. It will be lighter when I change over from the Muck 80 pipes to the CMD AB67. This an SG twin with MAC 84s.

Mike

 

[Don Ferrette]

On the scale at 13 pounds 9.5 ounces, race ready, no fuel. B)

 

[ClayGlover]

a little off topic, but are you guys using meters to set the needles on your twins? thanks

 

[Don Ferrette]

a little off topic, but are you guys using meters to set the needles on your twins? thanks

Absolutely!!! B)

 

[Mike Hughes]

Yup!

 

[Bob Morton]

Thanx Mike on the weight of your Twin F hydro

Don that was weight for a Twin F hydro

Clay yes I use a meter only way to go, unless someone else has a

better way :lol: :lol:

Any one else on the weight of there Twin f hydro??

Thanx

Bob MORTON B) B) B) B)

 

[Don Ferrette]

"Don that was weight for a Twin F hydro"

Yup. B)

 

[Eric Canto]

My SG Twin .84 weighs exaclty the same as Dons. I have a flow meter but do not use it to set up a twin unless the boat is brand new (first launch) or if something goes south(trash in a needle).

Eric

 

[ClayGlover]

My SG Twin .84 weighs exaclty the same as Dons.  I have a flow meter but do not use it to set up a twin unless the boat is brand new (first launch) or if something goes south(trash in a needle).Eric

so once they are both equalized, you just use a "doctor" that is shared by both carbs on a third channel to compensate for atmospheric changes?

 

[Eric Canto]

I know this is opening up a can of worms but...........no, I would not use a fuel doctor as they are one of the best ways to ruin an engine, or two(twin). My heat race twin is set up VERY conservatively....You would be amazed at how little you need to adjust needles on a conservative set up.........even through elevation and temperature changes. One of the first things Don Pinckert tought me was "you may not run GOOD rich, but you aint gonna run AT ALL lean!" The enginges in my twin are generally rich enough that they have plenty of "safety zone" before they even dream of going lean. I have run the same two plugs and needle settings at the last two races I went to.........one in Slidell La. and the other in Brandon Florida. Every pass between 78-85MPH, the plugs still look new. John Brown watched the boat run at both races....he will attest to how well the engines are synchronized and that virtually no adjustment was made between races. On a twin, the simpler, the better.

 

[Bob Morton]

Good info on the needles setting Eric thanx

Lets hear more on the weight for Twin f hydros

Hummm looks like those Andy Brown Hot Rods are lite hu :lol: :lol:

õ¿~ ya later

Bob Morton

pittsburgh,Pa

 

[Don Ferrette]

I know this is opening up a can of worms but...........no, I would not use a fuel doctor as they are one of the best ways to ruin an engine, or two(twin). My heat race twin is set up VERY conservatively....You would be amazed at how little you need to adjust needles on a conservative set up.........even through elevation and temperature changes. One of the first things Don Pinckert tought me was "you may not run GOOD rich, but you aint gonna run AT ALL lean!" The enginges in my twin are generally rich enough that they have plenty of "safety zone" before they even dream of going lean. I have run the same two plugs and needle settings at the last two races I went to.........one in Slidell La. and the other in Brandon Florida. Every pass between 78-85MPH, the plugs still look new. John Brown watched the boat run at both races....he will attest to how well the engines are synchronized and that virtually no adjustment was made between races. On a twin, the simpler, the better.

Very well put Eric, I couldn't agree more! I do not & will not run remote needles on a twin as you will never find two needles that will flow EXACTLY the same with the same amount of movement.

All of my single engine boats use the CMD/Kalistratov 3rd channel needles. B)

 

[ClayGlover]

Very well put Eric, I couldn't agree more! I do not & will not run remote needles on a twin as you will never find two needles that will flow EXACTLY the same with the same amount of movement.
All of my single engine boats use the CMD/Kalistratov 3rd channel needles. B)

how about a third doctor from a shared tank setup. A third channel doctor inline prior to the 2 additional needles at the carbs? just a thought.

sorry for the threadjack. Twins are the holy grail!

 

[Don Ferrette]

Very well put Eric, I couldn't agree more! I do not & will not run remote needles on a twin as you will never find two needles that will flow EXACTLY the same with the same amount of movement. 
All of my single engine boats use the CMD/Kalistratov 3rd channel needles.  B)

how about a third doctor from a shared tank setup. A third channel doctor inline prior to the 2 additional needles at the carbs? just a thought.

sorry for the threadjack. Twins are the holy grail!

No, no, no. It doesn't matter as both engines do not see the same load values. When you throw that big twin into a turn the inboard engine is loaded significantly more than the outboard one. Until you hit the staightaway that is ..............

 

[TimD]

The likelyhood that 2 engines in a twin run exactly the same on the same value on the meter is pretty unlikely - especially when you consider the load difference from the inside to outside motor.

Most of the twins here in Oz run 2 separate doctors joined to a common linkage with a collar.

You can fine tune the motors in practice - by reading the plugs, engine temps and so on, then flow them and use the collar on the linkage to adjust the doctors so that each needle is on the right spot for each motor. It would be very hard to do this consistently without the meter.

 

[Mitch Graber]

Roadrunner Twin w/CMB 90's------17 lb.

Eric,I noticed you looking at the wide stance at the rear

of that beast in Brandon......

The gold heads in it were giving me fits that race, and

the one before so they have been yanked out and replaced

with the new 2003 versions..wait 'til you see it next time.

I also set it up with CMD remote needles,I hope it works better

than what you are saying DON.This pair of needles were VERY

close in synch according to the flow meter,and the one that

richened up a little more than the other one was installed on

the right motor,hopefully that will help.

I can say Eric's boat was dialed in "sweet" the last two heats,it

looked great,and that is the same boat you got the 100 MPH

patch with,isn't it?

Mitch

 

[Bob Morton]

Ok great advice on the needles

Back to the thread,how much does your twin F hydro weight

Thanx

Bob Morton B) B) B)

 

[Mike Hughes]

Oh ya, I forgot my boat has a glass cowl that adds about 3/4 lb than the stock cowl. I bought my boat used and was a little oil logged. Hence the additional weight than the other guys. Still a lot lighter than one of the old eagle (first generation) that a friend of mine had. CMB gold heads in it. It was just under 20 lbs and awkward to lauch. What a back breaker.

Mike

 

[PHM Racing]

Screaming Eagle twin 90 13 pounds B)

Mike