Need some advice from out there. Here is the deal. Sanger 19'6" 1980 Family Skier. Right now it has a Stellings 11 1/2 x 15 prop and 18% gears. The 468 has a chevy steel crank, .250 long Crower rods, 10.5:1 SRP pistons, Comp Cam solid 260 @ .050 .637 lift staight across. New model aluminum Merlin heads 118 cc chambers 305cc intake runners 2.30 x 1.88 valve combo, 660's on an old style tunnel ram w/ Bassetts. It runs to about 6500 rpm and thats it. Seems like the thing should be able to spin harder. Advice on the gear/prop combo????What's the realistic expectations w/ this combo. Thanx for any help!!!
I used to run a 1972 Sanger family skier with a very similar
combo to yours. It was a 460 BBC 10.5 comp LS7 crank
& rods with a 638 lift 300 duration solid cam and iron
heads (with lots of work done to them). I had an Offenhuaser
tunnel ram with two 850's and a Vertex mag. With 15%
gears and a Menkins 10-7/8 x 15 prop we ran 96 mph
at around 6,800 - 7,000 rpm.
I hope that helps,
Marty
sounds to me that it's doing what it should do.
If it's just a lake hot rod you might want to leave it like it is. If you want to get after it more and like the RPM then gear down.
15's will get you up to 6,900 or close to it.
But if you really want to be the rock star with the quick deal put a 12% gear in that sucker.
It will be alot snappier with a lower gear for sure.
Thanks for the suggestions so far. I thought maybe a 11 1/2 x 14 prop would help it rpm more and make it quicker out of the hole. It's just a lake boat, but where it's ran a lot (Millerton-central cal) we run into a lot of squirt boats. Can't be embarrassed yuo know
It's alot cheaper to change gears than to buy a new prop.
If you like how your prop handles I would suggest a gear change. With a gear change you can always go back.
I'm thinking the above advise is correct & the rpm is where it should be.
Just another thought, What type of ignition are you running?
The reason I asked about the prop is that we have a Menken 11 1/2 x 14 prop in the shop. It needs to be checked out and looked at. Who would you suggest, and how much do you think that change would help??
You never know what it will do until you try it. I would suggest bringing both props to the lake with you so that you may try them back to back.
Cole Man.
Dave, everyone's advice here has been right on, with that cam, gear and prop and a decent size true flat, 6500 is a pretty respectable rpm to pull.
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