Verado 350 sci engine height
10-18-2010, 03:40 PM
#1
Gold Member
Gold MemberThread Starter
Verado 350 sci engine height
Hi,
I hope you all are well
We will start rigging my Phantom 25 next week. Almost all parts are now in house, included a very nice Gorilla jackplate. I have read about the issues about blow out and water pressure using the 2nd generation gearcase of 350 sci. Lets hope the new Poseidon is faster. Since I use a 20 inch midsection on a 25 inch transom, its important to get the jackplate mounted correctly. The reason for using a 20 inch midsection is to get the COG as low as possible. 350 sci is a tall engine, although its only 12 cm taller than a Promax 300
I wonder how high the 350 sci propshaft can be run before loosing waterpressure. I need it to be approx. 2-2,5 inches below the bottom to receive the top speed I need. I did have a Promax 300 some years back, and 2 - 2,5 inches below was spot on. I do not want to add a nosecone, as it will slow me down. Estimated speed will be approx. 82-83 mph. The Promax 300 (not X) pulled the boat to 76-77 mph.
The propshaft height will be approx 3,5 inches below at cruise (plus the fact that the water hits the prop higher due to 4 1/4 setback.
Look forward to hearing back from you.
All the best, Toffen
I hope you all are well
We will start rigging my Phantom 25 next week. Almost all parts are now in house, included a very nice Gorilla jackplate. I have read about the issues about blow out and water pressure using the 2nd generation gearcase of 350 sci. Lets hope the new Poseidon is faster. Since I use a 20 inch midsection on a 25 inch transom, its important to get the jackplate mounted correctly. The reason for using a 20 inch midsection is to get the COG as low as possible. 350 sci is a tall engine, although its only 12 cm taller than a Promax 300
I wonder how high the 350 sci propshaft can be run before loosing waterpressure. I need it to be approx. 2-2,5 inches below the bottom to receive the top speed I need. I did have a Promax 300 some years back, and 2 - 2,5 inches below was spot on. I do not want to add a nosecone, as it will slow me down. Estimated speed will be approx. 82-83 mph. The Promax 300 (not X) pulled the boat to 76-77 mph.
The propshaft height will be approx 3,5 inches below at cruise (plus the fact that the water hits the prop higher due to 4 1/4 setback.
Look forward to hearing back from you.
All the best, Toffen
Last edited by Toffen; 01-25-2011 at 02:07 PM.
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