Cam for ported head
Thread Starter
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Senior User
Joined: Jun 2002
Posts: 263
Likes: 1
From: British Columbia
Cam for ported head
Well my heads are off to the local porting god in the quest for 200cfm exhuast ports. I am leaving the intake ports un touched, except for a little clean up work. So it's bigger exhuast valves and bigger flow for me.
Anyways my question is; if my exhuast flow so much better than stock, is it still beneficial to run dual pattern cam? Would I now be better off running a regular grind?
I plan on running L and L headers to my existing dual 3" pipes. Man makin my mind up on a cam is harder than I thought!!
Nick from the frozen north
1974 F-250 4X4
soon to be 429
dana 60 front and rear
:-staun
Anyways my question is; if my exhuast flow so much better than stock, is it still beneficial to run dual pattern cam? Would I now be better off running a regular grind?
I plan on running L and L headers to my existing dual 3" pipes. Man makin my mind up on a cam is harder than I thought!!
Nick from the frozen north
1974 F-250 4X4
soon to be 429
dana 60 front and rear
:-staun
Elder User
Joined: Jan 2000
Posts: 966
Likes: 2
From: Crooked River Ranch, OR
Cam for ported head
I can't remember which cam Mfg. had an article on their website but they have found that a racing engine will make more power with a straight grind over a dual-pattern grind if the heads have been ported and most of the exhaust restrictions are removed.
I would recommend you also replace your intake valves when you replace your exhaust valves...remember the P.I. heads had the larger valves with the smaller ports (smaller than the CJ heads) and were superior over the CJ's for street use. I'm assumoing your going to one piece stainless valves? Much less likley to drop a valve head into your engine if you do. The stock valves are welded together at the stem and tulip...not good over 5000-5500 RPM. Deen
I would recommend you also replace your intake valves when you replace your exhaust valves...remember the P.I. heads had the larger valves with the smaller ports (smaller than the CJ heads) and were superior over the CJ's for street use. I'm assumoing your going to one piece stainless valves? Much less likley to drop a valve head into your engine if you do. The stock valves are welded together at the stem and tulip...not good over 5000-5500 RPM. Deen
Postmaster
Joined: Aug 2001
Posts: 2,882
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From: Nevada
Cam for ported head
Most cam grinders and racers still feel the Ford exhaust, even with FRPP C heads, responds better to a dual pattern cam. Ultradine and others who specialize in performance cams for 385 Fords carry this through their solid roller cam lines for unlimited engines.
I'm not trying to start a discussion of square versus dual pattern cams for 385s, just quoting racers and manufacturers who live those applications.
I'm not trying to start a discussion of square versus dual pattern cams for 385s, just quoting racers and manufacturers who live those applications.
Thread Starter
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Senior User
Joined: Jun 2002
Posts: 263
Likes: 1
From: British Columbia
Cam for ported head
I thought this might turn out to be a bit of a grey area. I know that Ford engines for the most part respond well to a dual pattern cam. I was just unsure if this was still the case with a properly ported head.
After I grenaded my 390 by cheaping out on some things that I figured would be strong enough, I have seen the light. Even tho I might have to wait a pay day or two longer to finish the build I have commited myself to building this one like a brick sxxt house. So yes I will be putting new stainless valves, retainers, and keepers, along with springs. I am also going to try out the magnum roller rockers. Anyways the list goes on and on.
Thanks in advance for the input.
Nick from the frozen north
1974 F-250 4X4
soon to be 429
dana 60 front and rear
After I grenaded my 390 by cheaping out on some things that I figured would be strong enough, I have seen the light. Even tho I might have to wait a pay day or two longer to finish the build I have commited myself to building this one like a brick sxxt house. So yes I will be putting new stainless valves, retainers, and keepers, along with springs. I am also going to try out the magnum roller rockers. Anyways the list goes on and on.
Thanks in advance for the input.
Nick from the frozen north
1974 F-250 4X4
soon to be 429
dana 60 front and rear
