help with 383 chevy thunder 383 vortec
#11
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+1 Multiple issues going on here . I can tell you with certainty that an 1988 Cobra drive will not live behind that stroker . They are very questionable behind a stock 260 hp 350 unless mounted in a very light boat . You can get a King Cobra lower out of Cali. for a couple k and i promise it won't break . Hang a 19 or 21p Viper 3 blade prop on it and go boating . Again , the regular Cobra drive is VERY weak and will do nothing but cause an oil slick on the water . My word is my oath....the deep
#12
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I've been running an OMC Cobra drive behind my 406 SBC for years. no problems just easy on the throttle coming on plane. I have a video on you tube of my Chris scorpion latest super charged 406 that will hit the water next week. just put new upolstery in almost ready to go. do a search for" Dave's 406 supercharged Chriscraft motor" on Youtube it also idles at 750rpm. no money for dyno but machinest estimates 500+hp
#13
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I've been running an OMC Cobra drive behind my 406 SBC for years. no problems just easy on the throttle coming on plane. I have a video on you tube of my Chris scorpion latest super charged 406 that will hit the water next week. just put new upolstery in almost ready to go. do a search for" Dave's 406 supercharged Chriscraft motor" on Youtube it also idles at 750rpm. no money for dyno but machinest estimates 500+hp
#14
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No problem. I've found that the shift linkage/shift interupter and bearing adjustment adjustment are critical to the life span. years back had a freind that was really knowledgeable on Cobra drives teach me how to build them right. rebuilt mine twice in 10 years. not big on wave hopping either
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just for info. I forgot to mention that OMC changed the angle on the dog clutch from 2 degrees to 5 degrees on later models for stronger engagement which is what I installed in mine when rebuilding not sure what year the change was made
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Yes that is the exact boat. Someone posted about an alpha one conversion. Has anyone here done that? Also the boat is 8' wide but donzi says it weighs 3500 lb....53 mph and 4800I or so rim's still seems low. My 22' Baja weighed 3200 pounds and had an 8' beam and with a stock 7.4 and bravo ran 64
#17
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How do you know for sure the engine is what the seller says it is? Maybe that it is not making the Power they claimed. Here is a link to the conversion for the outdrive.
http://www.sterndrive.cc/mm5/merchan...ory_Code=Cobra
http://www.sterndrive.cc/mm5/merchan...ory_Code=Cobra
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+1 Multiple issues going on here . I can tell you with certainty that an 1988 Cobra drive will not live behind that stroker . They are very questionable behind a stock 260 hp 350 unless mounted in a very light boat . You can get a King Cobra lower out of Cali. for a couple k and i promise it won't break . Hang a 19 or 21p Viper 3 blade prop on it and go boating . Again , the regular Cobra drive is VERY weak and will do nothing but cause an oil slick on the water . My word is my oath....the deep
#19
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Sorry i have to disagree with you..one of my customer's has a 211 liberator with a 468 alunimum head ford that pumps out 490 hp and 600 ft lbs of tq @ 5100 rpms..i did the engine over 10 yrs ago and his dog clutch has had no issues up until last year when he hit a rock and scattered the lower..he is also running a 16x20 labbed mach 4 blade..it all depends on how you treat the cobra drive..
#20
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the Cobra to Merc swap is really difficult. you unbolt the Cobra stuff, sell it on Craigslist, and bolt the Merc stuff in...hardest part is making the backwards throttle work without replacing. although i have seen more Alphas die than Cobras. but there are a lot more Mercs out there. percentage wise i don't think there is much diff. OMC copied the Alpha as soon as Mercs patent ran out.