New Member - Need help with 1967 restoration project

Denise,

The horsepower loss numbers he quoted assume that the mixture is correct for the altitude. The modern direct injected motors should handle this automatically as do the modern cars.

An un-supercharged piston aircraft engine will produce about 75% power at 7500 feet at full throttle and will need to be leaned to do that. The leaning can be done from the cockpit. The air pressure decreases with altitude so there is less oxygen available to the engine.

jim

 

Well put Jim. The air is thinner up there so there is less oxygen which results in a loss of power. Something else that people note about Tahoe is the purity of the water. It is something like 99% pure, so your boat tends to be more dense in the water than say in sea water. What does that mean? It means the boat appears to be heavier. It's true too because the cruiser sits higher in the water down in the Delta than it does when it's on the buoy at Tahoe. Isn't science interesting? Although I have seen Arneson up there with his turbines and the air doesn't do a darn thing to that noisemaker......

Thanks for the West Coast respect Daniel and Denise. I grew up in Arizona and have frequented all the lakes between here and there growing up. I would definitely be interested in attending a get together, especially if it's in the Delta area.

Thanks too for all the motor advice. At this point, I will try to find the happy medium between added weight and additional horsepower. My gut tells me that due to the power loss, I should lean toward more horses. But what am I getting myself into performance-wise at the lower elevations??????????

 

Jbarra,
There is no replacement for displacement. Think of the fun down the line pulling a couple of barefooters up from a deep water start and your Dyne won't even breathe hard with the right motor.

 

Most Dynes are propped for water skiing. The sort of standard prop is a 17. The modern motors will hit the rev limiter at around 50 or less with that prop, but they will pull like a train. If you have a 200 and prop it for speed, the boat will get into chine walk at around 70. I guarantee you will not enjoy that.

Part of the reason that I suggested considering the big blocks is because in the used market (for compliant motors) it is difficult to find anything more than 150. I run a 150 and I am happy with it and they are plentiful. You should consider one. If your heart is set on something bigger (used) the big block 200's are easier to find.

The boat is a blast to drive with either. It will bring out the hot rodder in the most conservative of people.

jim

 

My last full restoration project was a Cherry Red '65 GTO Hardtop, so there definitely is some hotrodder in me...........but I have no plans of doing 70 in an 18' fiberglass boat that weighs less than 1000 lbs! It's more for the nostalgia of it all. I just hate to see old unique cool toys go to waste in a barn somewhere. <img src="{SMILIES_PATH}/icon_biggrin.gif" border="0" alt="Very Happy" title="Very Happy" />

JB

 

Shoot......my reply disappeared!

Jim, thanks for explaining that!

Jeff......As it stands now it will be after the New Year for the next Delta meet I think. In the past they have used Windmill Cove a few times including one weekend camping trip in June of this year. I am assuming there will be another for 2007.

My oldest, Taylor, moved to Mesa AZ last November. My two younger boys and I are leaving on Saturday to spend Thanksgiving with him. Last year he was alone on Thanksgiving and Xmas so I am going to go and cook him dinner.

There are also a bunch of fellow boaters that live there from various boards and I am hoping for some time on the water with them.....PowerCat guys for the most part. I think my boys would get a thrill out of watching and riding in some fast boats. My Elgin tops out at about 32-35 mph and that is on glass....hey, I got kids in the boat and don't go there.

I got to drive one of the modified Cats two years ago at 50mph on the river......WOW! I am still talking about it!

 

You mean you don't want to do this??

Photo credit to Greg Terzian, Scream and Fly administrator.