Building a new motor
03-13-2003, 11:44 PM
#1
Building a new motor
I am in the process of building a new motor. Last year I was running around 73 mph with a 300 hp 7.4 with roller rockers, intake, carb, and exhaust mods. I want to go faster, but am not sure of what new equipment to buy. I did purchase a set of rectangular port heads to replace the stock oval ports. But as for intake, cam, and compression.....I am sort of up in the air. Not sure what to go with. I would like to make hp in the upper 400s at the least but remain naturally aspirated and in the 5000 rpm range. I have built many drag race car engines.....but these have no real limit to rpm range. So, with rectangle port heads......how can I get 475-500hp out of my 454? Any help is appreciated.
03-14-2003, 05:25 AM
#2
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A good friend of mine has been building engines for me for over 20 years. He has bulid 454ci engines with well over 600hp, and they last for years. Give me a call or e-mail and I will give you all the info you need to talk with him.
Warren
High Priority Offshore
Warren
High Priority Offshore
03-14-2003, 11:21 AM
#4
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What prop and how much RPM are you turning? A buddy of mine just bought one of these last fall with the same power and at 4700 RPM with a 23" Mirage we radared him at 61 MPH. I figured with 500 HP he would be in the low to mid 70's. As for your motor Merlin oval port heads, an oval port single plane intake, a hydraulic cam in the 228/235 @ .050" with .550 lift on a 112+4, good exhaust, and a holley 750 carb will give you some nice gains. My 210 Sport did 66 MPH with the 7.4 L and when the above mods were done it did 77 MPH and was very quick. Do yourself a favor and get a GPS or radar gun on board and double check that top speed. Nothing is more fun than beating a guy that is claiming big numbers with a "slower" boat, and you don't want to be on the wrong end of that race.
03-14-2003, 01:21 PM
#6
OK, first....the boat was stock with 300 hp. Then an edelbrock performer intake, roller rockers, an 800 holley, and imco exhaust were added. This felt pretty good. But, not enough. I am not really looking to wake up the 300 hp 454. I want to build from the bottom up, but I don't know what to choose to make alot of power at (what is to me as a drag racer ) low rpms (5000). Someone send me an e-mail. Give me a phone number. Anything, I need help. I have been milling over different combos since december and the season is fast approaching.
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