MILD THUNDER

iTrader: (3)

For months now I've been having this conversation with a buddy of mine. He has a 42 Fountain with big procharged power. He has 1.36 Gears in his SCX with SC lower.

He keeps telling me that his problem with acceleration was due to the 1.36 30p prop combo. Because he said the boat accelerated so much better with the 1.5 gear 30P prop (6500RPM topped out). Well, I been trying to tell him you cant compare that scenario, and a more fair comparison would have been the 1.36 with a 26p prop.

Last season with the 1.36 and 30p prop, he turned 6000RPM all out. Which is where he wants to be. So he wants to install 1.5 gears, with 34p props, and he said the boat will hands down be faster and accelerate 10x better. We added about 80HP per side with some changes. So my guess is to stay at 6000RPM he may need to go up 2'' of pitch. I tried suggesting not changing anything since lets see how the boat responds with the engine changes. But he has been told that going to 1.5's will turn it into a MONSTER. I just cant see the gear change being that dramatic. Maybe im wrong.

My questions are for the guys who have ran both setups. I personally have never ran anything other than 1.5 gears in my stuff.

By going to 1.5 36p prop over a 1.36 32p prop setup...

Will the boat accelerate harder, and how much? He seems to think its gonna go from sluggish to neck snapping by making the change?

Will the top speed change??

Which setup would be easier on the drives??

abones

Sluggish to neck snapping I doubt it, I believe the 1:36 with the 32 prop would be easier on the drive, how long wll the drive last if he slams the sticks with either set up? I don't know just sayin.

GPM

He might feel something with a 1.5 and a 32, doubt it will be neck snapping in a 42. What RPM will he see the extra 80 HP ?

mike tkach

iTrader: (3)

i believe his imco scx drives are 1.3 ratio.

mike tkach

iTrader: (3)

peak hp of 1195 was at 5900 rpm.

MILD THUNDER

iTrader: (3)

Actually I was wrong on the 80HP. He picked up like 100FT lbs from 3000-3800, and from 3800-5800 he was up 60-90FT lbs.

HP wise, up about 75HP from 3500-5800. Around 6000RPM he only up about 40HP and 40FT lbs. The goal was more midrange.

Also getting rid of his old carb setup, in favor of some new C&S blow thru's. Hopfully those will clean up his fuel curve, which was just not good for anything. Fat down low and lean up top.

FIXX

iTrader: (2)

theirs more to the story,,he is allso going from a -1 to a -3 shorty if im not mistakin...

The boat is going to get from point a to point b faster with the 1.50 then a 1.36 ratio..


I give up,let him figure it out..

MILD THUNDER

iTrader: (3)

Actually it looks like 1.34 according to this?

http://www.mkhammer.com/imco-sc-lowe...-p-302570.html

MILD THUNDER

iTrader: (3)

Nope. He's keepin the -1 now lol

GPM

Does the HP fall off or could push them to 6100 if need be and have a better hole shot.