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12 CELL OUTRIGGERS and ENDURO
By Ian Williams
I must admit that this is not the article that I set out to write, but having
read a piece in Steve Hill’s web site, I was interested to learn that you are
running 4 minute Enduro races over there. As some of you may know, this is the
way we run over here in the U.K. and the rest of Europe.
I was interested to see the setup that Ed Hughey was running and the
estimated speeds involved. Over here, the guys who are running Dual Gear drives
use the following setups for 4 minute racing. Two 12 turn double motors, 2.19:1
ratio and Octura 1750 prop. This set up is good if the water is rough, you can
get away with the bigger prop. In calmer water we would use a 1747. We have also
found that a 1747 prop on 2.09:1 ratio also works well, but if the water
conditions flatten out you can be a little short of run time.
You are no doubt wondering about boat speed. Well at our speed day late last
year, one of my customers and I ran our boats with a normal oval race set up as
explained above, and we were both within 0.4 mph of each other at around 42 mph.
This season as well as my geared boat, I have been running a direct drive
Cobalt motor, an Ultra 920-8M (8 turn) [With Hughey hardware of course]. The set
up here is, X435 prop in calm water, X637 or X438 if the water is choppy and
maybe the Y535 somewhere between the two extremes. At the moment the Ultra
powered boat has the edge, being about ¾ to one lap faster than the geared
boat. However we are continuing to develop the geared boat as I am sure the
geared drives have more potential. Ed’s setup with the low numerical ratio and
X642 prop looks promising.
If you are wondering why we have not got our setups nailed down tight after
racing Enduro for so long, the reason is simple. This is the first full season
that we have been allowed to run "open" motor classes. Up until now
all 12 cell classes (mono and hydro) had to run a restricted format. This meant
the only legal motor for 12 cell was the Graupner 700 BB Turbo. Add to that, the
fact that a couple of seasons ago we were racing 3 minutes duration races for
hydro and 4 minutes for monos, you can see that we suddenly had to find an extra
minute of run time to comply with Naviga classes. Of course it is all change
again, and it has taken us quite a chunk of the season so far to come to terms
with the new format.
Speaking about the 700 motors, I see that there has been some discussion over
there of a cheap, easy to run class, where costs won’t scare off potential new
racers. Well, I have to agree with Ian Pearson and Alan Shilitoe of Astec, the
700 motor certainly fits the bill. I realise that some of you don’t like
sealed can motors, but the motor is cheap and with care will last a full season.
If you add up the time, and cost of 540 com skims, brushes and perhaps motor
blowups, not to mention the initial costs, the 700 starts to look more
attractive. Over here you can get two 8.4 volt 700 BB Turbo motors for the cost
of one good modified 540!
Alan and Ian probably know more about the mono racing than I do, but as an
example, last year I ran my Bat Boat (stepped hull) with an 8.4 volt 700 BB, 12,
2000 cells, and an X640 prop. Speed was in the mid to high 20’s and run time
around 5 minutes 20 seconds.
A 12 cell rigger will run the same motor/cell combo but with a P747 prop will
give around 4 minutes 35. Or with a 1742/3 prop will give around 4:15 or 4:20
depending on water conditions. Best speeds are with the 1742/3 at around 36 mph.
I hope the above has been of some interest, and if time and Donnie allow, I
hope to write some more. If everything is OK, I aim to look at 7 cell 4 minute
racing next time.
This Article was written by Ian Williams Exclusively for Rum Runner Racing. Use of this article is prohibited
without written permission from Rum Runner Racing.
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