1:36
 

Yet another question. I am some what interested in a boat with 1:36 gears in the lowers. What is the main difference here ? Are they looking for top speed, cruising speed ? I have only owned boats that have the 1:50 gears in them.
Will these gears hurt motors ? Cause extra stress on the boat.
Also the boat has 500 EFI's in it with whipples on top, is there room for intercoolers down there, with a stock swim platform ?
The boat is a 02' 38 Lightening.
The boat is in great looking shape, I know survey, it only has 90 hrs. on it, just looking, kicking tires, but getting serious...
Thanks for your help.
~~ Reggie ( in my next life I hope )

Don't be afraid of the 1:36. He may have started to run out of prop options. When you get up in the mid 30" pitch range it is time to consider gear change.
Jim

Older 502's all came with 1.36's behind them, at least according to my clymers manual. my boat has 1.36's.

less torque on the propshaft and less pitch on the prop is the result. Other than that, no difference AFAIK.

We ran a 35 Lightning, with 540 whipples. Had 1.5 gears and was running 34 pitch prop. Went to 1.36 gears to go down in pitch. I was getting to much stern lift from the big pitch props. I think it make about 500 rpm difference. If the boat is propped right you wont know the difference.

the ratio does as mentioned when approaching end of prop selectoin. in many instances the set up is off and the slipage is way up , thus ending up with no more prop.
many setups use the 1:36 ger to keep prop speed up, which increases handling and stability , especially in high speed applications.
this gear also helps with mid to high rpm acceleration when the engines being used turn very high rpm.

It has a 30 inch prop on it.

most of the 38's i have played with have 1:50 ratio drives. typically a 1:50 with a 32p and imco shorties spining 6000 rpm run around 103. mid nineties at 5500 maybe 96 or 97.

sounds as if your slip is high.

monstaaa, How do you know if his slip is high he hasn't posted speed or rpm? Your #'s show about 13 percent do you conceder that high. Just wondering.
Jim

my mistake i read the 90 hrs as speed. as for slip 103 -105 for 32 4 bld's is roughly 12 percent slip, which for merc wheels is pretty good.

additionally when 1:36 is used for standard length and 30's that's a hint of slipage. this boat should run a minmum of 90-92,

I would think if it's got whipples and 30's it hadn't been played out yet. Doesn't seem right to have whipples without inter coolers.
Jim

intercoolers are cheap insurance to help against detonation. will probably give another 50 + horse power i would think. may require hatch modifications depending on the x dimension.

Reggie, never seen a set of Whipples from Dustin without intercoolers, are you sure they dont have them mounted under the blower. If not im sure you have room to put them on without cutting the hatch.