BenPerfected

The real home run is to get the X dimension right. The new high 'X" on an extension box with a four blade prop will get the speed. I would try and find out what is ideal for your boat. I good place to start is JimV an this board. He has solid experience with high X on a single engine 27-30 boat with an extension box. I would be surprised if you can't get +5 mph.

Cord

iTrader: (2)

Here is a poor pic...

29scarab

I have another question.

Those holes in the box look like for adjustment. When I put the box on how do I know what set of holes to use?
I know you want a optimum X-dimension, but how will I know where the right ones are.?

Where will the box put my outdrive compared to when it was bolted straight onto the transom. Do I take measurements before unbolting my outdrive with it parallel to the ground or what?

You guys are heading me into the right direction, but if there's some more info out there, I sure would appreciate it.

I want to tell ya thanks for the info so far, but keep it comin'.

cobra marty

Take a straight edge and run it along the bottom of the 'V' back to the nose of the bullet of your drive and measure it, how far below this straight edge the nose is. When you bolt on the box I would use the hole that will put the nose 1" higher than you measure stock. Probably it will be the middle set of holes.

Cord

iTrader: (2)

Yea, before you take the drive off, I'd measure your x-dim. Take a straight edge off the bottom of the hull and run it back to see when the prop is. We can all talk the numbers up, but it's that alignment that matters. Now ask yourself how the boat is handling, how it planes off. If you get blow out or slippage the box will help improve that. If you can get on plane with a 3 blade mirage then you can go higher. Ultimatly, the box will allow the x to be set at least an inch higher. I honestly don't know anything about the scaarab setups so I can't offer much more help there.

Those holes are for adjustment. If you machine them into slots then you'll be able to adjust the box without tearing everything apart. I'd highly recommend the modification.

454hoho

You should see the block of plate thur or fri/sent 3 day service

cobra marty

I'm doing mine with the IMCO ears, rams, drive cap and going to run the hoses into the side of the box and not thru the transom to keep a cleaner look. I'm thinking of tapping the bottom for a drain plug- What does everyone think?

The IMCO ears I used before used hex head bolts and use a long allen wrench to get down in the ear with the nuts on the inside of the box. No studs or nuts in the ears.

Cord

iTrader: (2)

454-thanks!

Cobra-definetly tap the box. Mine came that way so I never mentioned it. I replace the pipe plug that mine came with a brass mercruiser block drain plug. Hopefully they changed the mounting system for the ears. Those studs and nuts really sucked!

29scarab

That brings up another question.

Is there one ext. box better than another? What makes one better if so? What are the advantages?

What is the story on the drive shaft of the Stellings compared to the torsional driveshaft of the IMCO box. Is one better than the other. Is there an advantage of buying one new compared to used??

Just a couple of questions for inquiring minds......

Thanks

Bill272

Your PM box is full... Send me an email (I can't get into OSO at work). I might have a steering system that would be perfect for your setup.