Which heads?
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Freshman User
Joined: Aug 2006
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From: MInnesota
Which heads?
I am doing a 302w to a 351w swap in my 89 f250. I have a donor truck with the 351 but I want to rebuild it first. My main question is which heads should I put on my new engine to get the best low end torque? I want to use the World heads but don't know which ones to get. Should I get the Windsor Jrs. or the Windsor Srs. All your help would be appreteated. I am goint to be running a comp truck cam that is compatable with seed density. Thanks. -Jake
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Joined: Apr 2003
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From: Edmonton, AB Canada
Smaller intake valves will give you a flatter torque curve. The larger intake valves will put your peak torque at higher rpms, which is not where you want it. Larger exhaust valves will also do the same. I dont personally know anything about the world heads, but that is just some general info on torque in comparison to valve size. Hope that helps.
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Joined: Mar 2006
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Hey man, not to spoil your project or anything, but if you plannin on going with speed density the aftermarket head may cause you running problems. I have a 92 302 and i put a set of trick flow twisted wedge on it and it screw my running all up. The truck would actually only run right when it was wide open, but after a couple of wide open passes it went lean and i burnt a piston. After that i decided to go with a ford production head and put a set of gt40p heads on it, and i had the same trouble. I've done just about everything that can be done to my truck with the speed density, a cam throughs everything off if you get a good one, so what i've discovered is to either do a good port polish on the stock heads and let it be, and polish and match the intake, with a stock cam or an h.o cam, and it will perform and be reliable. But if you going with a lot of mods you may wanna look into converting to MAF system.
Hotshot
Joined: Jul 2002
Posts: 14,285
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From: Bend,OR
heads will not mess with sd. cam selection is key with a lob seperation of 114*or more for the ecu to be ok. compcam 35-255-5 would be the cam i would use in your situation. check out www.fordfuelinjection.com for more info
the roush 200's are a good head but you pay for them. I suggest having the stock e7's worked over a bit or locate some gt40's from a lightning. dont get the gt40P's , spark plug angles suck and require a special header.
keep the comp ratio at 9-1 and you can still run regular unleaded with iron heads, but any higher and high octane will be needed.
runing a set of headers, reworked Y pipe and 3" exhaust out stock location will also help with low end
have fun
the roush 200's are a good head but you pay for them. I suggest having the stock e7's worked over a bit or locate some gt40's from a lightning. dont get the gt40P's , spark plug angles suck and require a special header.
keep the comp ratio at 9-1 and you can still run regular unleaded with iron heads, but any higher and high octane will be needed.
runing a set of headers, reworked Y pipe and 3" exhaust out stock location will also help with low end
have fun
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Freshman User
Joined: Aug 2006
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From: MInnesota
Thanks for all of your help. I will probably just use the stock heads reworked. What pistons should I use so that I dont get the compression too high? I want to go hyperpneumatic. Thanks. -Jake
