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#31
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Live in Cedar Rapids. We have a crew of about 8 guys and 4 boats to choose from. Ski the Cedar River Thursday nights and either the river or Coralville Res on Saturday mornings. I also spend 3 weekends a year in Okoboji
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#32
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Based on the typical performance reported out of 454 powered MC's from the late 80's/early 90's (very few reliable datapoints), the hp numbers that Indmar published (390/425hp) sure seem optimistic to me. All of the other marinizers (PCM, Mercruiser, OMC, etc) rated their standard 454 around 330hp, and their HO in the 390-425hp range. The 19' ski boats Ive driven with the 330hp "base" 454 come out of the hole about the same as the small block Ford powered boats, and top out 2-4mph faster (upper 40's). They would have a holeshot advantage if they were propped equally as the small blocks, but they generally have larger wheels (13x15 or 14x14 vs. 13x13 for 1:1 boats) in order to keep the revs in check at WOT. Ive read that the 330hp longblocks were really only good for 280-290hp from the factory, which seems like a pretty reasonable claim... boats with HO 351's from the same era (285-310hp) run very similarly up top.
Of course, its possible that Indmar only sold HO 454's and the people reporting back performance had poorly tuned (or tired) motors. HO engines had rectangle port heads (which require rectangle port intakes) so you can be pretty sure which you have by looking up the casting number on the intake manifold. PCM HO's were pretty rare and LH only... Ive never laid hands on a boat so equipped. Our 454 (surely a 330hp version originally) had been given a newer top end prior to coming to us, and was basically consistent with the HO package, minus the cam. It was a real dog out of the hole, but was a screamer up top! I would guess that a true 390+hp HO 454 would push a 19' Prostar into the 52+ mph range, at least. 55mph wouldnt surprise me either. Generally speaking, a healthy small block will be quicker than a big block boat. Especially if youre talking about a modern vortec or LS motor. Theyre lighter weight and run smaller props (as they can spin higher up top without over-revving).
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PCM 351w, 350hp |
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#33
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Its official. I go pick up the boat the weekend of the 12th of Jan. I will make its own thread when I get back with it so you guys can point out all the things that are wrong with it ...
![]() In the meantime, I will have to spend a day or 2 getting the X5 ready for its new towing assignment |
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#34
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I have a friend who did everything he possibly could to a 1977 S & S to make it go fast, spent a ton of money on engine upgrades. The end result was maybe 1-2 mph improvement. The only way direct drives like ours will ever go over 50 mph will be while being towed on the highway. Since our boats are always "trimmed down" they just can't go fast, period. |
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#35
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Quote:
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- Peter TIRE & WHEEL SALES email:tiresplease@gmail.com SPECIAL PRICING CONTINUES Two 14" Aluminum wheels $195 Two 15" Aluminum wheels $215 Four 14" Aluminum wheels $370 Free Freight within lower 48 Steel and galvanized wheels available. Spare tires too. |
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#36
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Regardless, I maintain that a ski boat hull thats good for ~45MPH with a 240hp small block Ford should be good for 52-55mph with a HO 454 in the 400hp range. As far as "never breaking the 50mph barrier" goes, come on out to CT and you can hitch a ride in a late model Correct Craft good for 52+mph in stock form, or a modified vintage big block CC that'll take the 60mph mark down. Fun stuff. KBrighton, I know of some skiers (and inboard nuts) in the Des Moines area that would love to take a gander at that big block Prostar... they have some fun old CC's too.
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PCM 351w, 350hp Last edited by TRBenj; 12-19-2012 at 11:23 AM. |
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#37
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My old 89' PS with 454 at times would pin the speedos at 50. otherwise they would hover 48-49 mph.
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#38
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Definitely marinization by Indmar....
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Ted W Hook Em' Horns |
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#39
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#40
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Beautiful boat!
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1989 Tristar 190 - Indmar 351, 250HP, 1:1, 450 hours |
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