increase torque on a 460 engine

[rejelava]

increase torque on a marine 460<br />March 21 2003 at 3:48 PM<br />No score for this post Réjean Lavallée (Login rejelava)<br />from IP address 207.236.99.253 <br /><br />--------------------------------------------------<br />My single 460 engine is in a 1989 32 feet cabin cruiser with a King Cobra outdrive. I need 70 to 150 extra horsepower to plane my boat when it's loaded. Presently, my stock engine develops 330 hp. My block model is D9TE-AB and the head is E6TE-DA. It's been recently rebored 0.030. I am presently doing a port and polish on my heads. Should I stoke it? If so with what? Should I simply change the cam for one with more duration and lift???

 

[Dhadley]

Re: increase torque on a 460 engine

You can easily gain 125 hp on that motor. Intake, carb and cam is the key. The polish doesnt do much at the rpm you will be running. You will need a good exhaust system also. <br /><br />Running a King Cobra? Or a Cobra drive?

 

[6MISFITZ]

Re: increase torque on a 460 engine

Going 30 over will not change near as much as a a very small increase in valve size. More hp and torque means you need more air in and out and nothing does that like bigger valves. <br /><br />However in a marine setting with constant load and heat, a marine cam / lifter kit is the best place to start. If you can find high temperature valves (usually sodium filled for high temperature applications) then this will make a huge difference.<br /><br />Mike.

 

[DJ]

Re: increase torque on a 460 engine

R Lavallee,<br /><br />The key to getting more power out of a 460 (7.5L) is to make it breathe better. Stroking is not necessary.<br /><br />Cam changes will help, so will porting and polishing. However, your biggest challenge is going to be the exhaust system.<br /><br />Installing free flow manifolds will help and thru-transom exhaust will also help.

 

[Bondo]

Re: increase torque on a 460 engine

Why don't you skip on over to the boards at,<br /><br /> http://www.hotboat.net/ <br /><br />There's a bunch of guys over there who Like building Big Bad Fords...

 

[Dhadley]

Re: increase torque on a 460 engine

The 1989 "King Cobra" did not have a "King Cobra" drive. It came with the standard Cobra drive which wont take a lot of torque. <br /><br />Someone may have changed it to a cone clutch drive but its better to check now.<br /><br />Good luck!

 

[Boatin Bob]

Re: increase torque on a 460 engine

Dhadley....I have to disagree about comment about the 1989 King Cobra drive. 1988-1989 did have King Cobra drives however there were still dog/clutch style, the cone clutch didn't come out until 1990. These pre 1990 drives were a bigger, beefier drive built to handle the big blocks, the amount of drive oil they hold is 108 oz compared to standard cobra's 64 oz and they are much heavier. I know this because I have 2 460's with these drives in my boat.

 

[Dhadley]

Re: increase torque on a 460 engine

The early King Cobra packages have the standard Cobra upper with the V8 outboard style lower as you mentioned. These will not take a lot of torque, which the 460 has a lot of to start with. <br /><br />The cone clutch King drive will handle 600 hp fairly well. Trust me on the torque - we ran the OMC King Cobra race boats.<br /><br />Good luck!

 

[rejelava]

Re: increase torque on a 460 engine

Thanks everyone for your response. I plan to use my OMC outdrive becouse nothing else will fit on it.<br /><br />My main problem at this point is my lack of torque. Can you suggest a cam (duration and lift). <br /><br />I was told that the ideal solution would be to stroke it. If so what do you recommend?

 

[magster65]

Re: increase torque on a 460 engine

An 'RV' grind is best. Better flowing exhaust and aluminum intake will definately help.

 

[conimicut1]

Re: increase torque on a 460 engine

if you have $, get new heads before chossing a cam. Power is really in head design. Endelbrock makes a replcement head that is excellent. But if you're going to spend the $ for heads and cam, then a complete rebuild may be best.