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What up everyone I'm new to this forum but all i've heard is great things i just picked up a 77 challenger with a marine 460 motor its got a mild rv cam. and a 750cfm holley, the pump is a jacuzzi with a lot of work including a energizer kit evidently but i tested it today at full throttle im achieving 50.2 mph at 4300 rpm should i step up to a 850 i hear the fords are thirsty bastards?
 

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Congrats man, im running a mild built(very mild) 460 and i am running a 750cfm holly and its just not enough but im also running at 5000rpm. But im going to a 850dp cfm this weekend i will let ya know how she runs. But i was told to go bigger cuz fords like the fuel...
 

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IMHO if you are stock, stay with the 750 Holley and enjoy the gas miliage. You can always jet it up a little. Fords do like a lot of carb. So when you start to build the motor, a 850 DP is a great carb but you will wish you had a 1050 Dom.
 

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If It wouldnt flood the thing i would throw a dominator on it, i just cant figure if i need more motor cuz the pump work or cam/intake and carb would bring rpms up along with speed, its got a mild rv cam now but maybe i should throw something raspy in it
 

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If It wouldnt flood the thing i would throw a dominator on it, i just cant figure if i need more motor cuz the pump work or cam/intake and carb would bring rpms up along with speed, its got a mild rv cam now but maybe i should throw something raspy in it
Leave the cam alone and step up the timing and toss an 850 holley on it. What 750 do you have on it now? Could be made to work better with alittle work. If you tell me it's a 3310 series then thats the problem. BUT with alittle work they will work and be less spendy at the pump than a 4781 holley. M
 

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Discussion Starter #7
its a differn't boat

So i found a guy on craigs list no joke 850 carb 50$ figured why not check it out, drover over it was a brand new 850 dp he obviously had no clue of pricing I offered $40 Figured why not he took it, installed that and set timing to 39 degrees at 2000 its a way differnt boat huge differnce. Thanks for all the help this weekend Joe (motoMattox)
 

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What up everyone I'm new to this forum but all i've heard is great things i just picked up a 77 challenger with a marine 460 motor its got a mild rv cam. and a 750cfm holley, the pump is a jacuzzi with a lot of work including a energizer kit evidently but i tested it today at full throttle im achieving 50.2 mph at 4300 rpm should i step up to a 850 i hear the fords are thirsty bastards?
Welcom Chad , IMO your maybe "down on power a bit" , odds are your "energized" Jacuzzi has an "A" and you should be turning it somewhere north of 4600 (to maybe 4900) (depending on altitiude and assuming your Tach is correct ) the boat should closer run mid 60's and 750 is probably optimum Carb , you didn't mention if your jet had nozzle trim but its a must to help free up the boat and get it to run faster Tom
 
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