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Tech Talk => Engine Mechanical / Electrical => Topic started by: FordLover on May 05, 2015, 02:02:55 PM

Title: Cam Selection
Post by: FordLover on May 05, 2015, 02:02:55 PM: You know what is frustrating? Not being smart enough or knowing enough about engines to make an educated decision on what cam to select. So I basically have my engine 90% purchased but the cam is KILLING me. Talked with a couple technicians on a couple of different cam sites, one was super afraid of reversion the other acted like it was no big deal. One said one thing the other said the opposite. I don't know. Just kind of tough and I don't want to make the wrong decision and blow my engine up.................again. But I do want it to perform and be a bad@ss monster. You know what I am saying? Think I need some cheese with my whine. :banghead:
Title: Re: Cam Selection
Post by: philofab on May 05, 2015, 02:09:10 PM: There are a lot of variables so it can be a difficult decision. Post up about your boat and engine and we will all offer suggestions and confuse you more.
Title: Re: Cam Selection
Post by: steves86ta on May 05, 2015, 02:13:13 PM: What he said... give us some details and we can help! O0
Title: Re: Cam Selection
Post by: FordLover on May 05, 2015, 04:57:32 PM: Lol. Confusing indeed.

521 Ford
AR aluminum Cobra Jet Heads. Unfortunately don't have any info on these heads except 680 lift is the max they can handle, granted I will get no where near that.
10.5 to 1 compression
Dual 650 carbs
18 foot bahner
JC pump with a impeller
Water injected headers

What else do you need?

Was headin towards hydraulic roller due to recommendations, but the specs on it are the issue. Can't afford to make a mistake.
Title: Re: Cam Selection
Post by: LakesOnly on May 05, 2015, 06:34:12 PM: How much horsepower do you want? Based on the limited parts combo info, I can say that 600 hp should be easy with a flat tappet camshaft. If I had any say in it (or we were building your engine), I'd strongly advise against the hyd roller camshaft.

If you want to talk about it then please call directly, I don't have as much time as I used to for pecking at a keyboard on forums.
Title: Re: Cam Selection
Post by: crewchief22 on May 05, 2015, 08:16:16 PM: I would go with anything ^^^ he recommends.
Title: Re: Cam Selection
Post by: GT Jets on May 05, 2015, 08:18:30 PM: Quote from: crewchief22 on May 05, 2015, 08:16:16 PM
I would go with anything ^^^ he recommends.

Ya. I don't know. What a hack. :o

GT
Title: Re: Cam Selection
Post by: FordLover on May 05, 2015, 08:33:24 PM: Quote from: LakesOnly on May 05, 2015, 06:34:12 PM
How much horsepower do you want? Based on the limited parts combo info, I can say that 600 hp should be easy with a flat tappet camshaft. If I had any say in it (or we were building your engine), I'd strongly advise against the hyd roller camshaft.

If you want to talk about it then please call directly, I don't have as much time as I used to for pecking at a keyboard on forums.

I am goin to assume Glenn is messin around. Lol

Sure, I will totally call. Just go to the high flow dynamics site and call the contact number?
Title: Re: Cam Selection
Post by: 76NORDIC on May 05, 2015, 08:35:12 PM: LO definitely knows his shit about Ford's

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Title: Re: Cam Selection
Post by: jyeager on May 05, 2015, 08:45:21 PM: Quote from: 76NORDIC on May 05, 2015, 08:35:12 PM
LO definitely knows his shit about Ford's

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If not lakes only Chris strab at strab/fox well technologies
423 391 7774

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Title: Re: Cam Selection
Post by: GT Jets on May 05, 2015, 09:40:17 PM: Quote from: FordLover on May 05, 2015, 08:33:24 PM
I am goin to assume Glenn is messin around. Lol.

Absolutely. I have a ton of respect for anyone that can make a Ford run like it's scared.
Title: Re: Cam Selection
Post by: Flusher on May 06, 2015, 12:09:51 AM: Quote from: FordLover on May 05, 2015, 04:57:32 PM
...AR aluminum Cobra Jet Heads. Unfortunately don't have any info on these heads except 680 lift is the max they can handle, granted I will get no where near that...l

Not entirely true!

Duration dictates compression ratio, not lift. Albeit, lift is somewhat tied to duration in that a lobe profile can only actuate a given type and diameter of lifter so fast. With that being said, within a given family of lobe profiles, you will see that as lift goes up, so does duration. That is where roller profiles shine. The intensity at which a roller lifter can be actuated is much greater than with a flat tappet. This intensity can be pushed further with a lobe designed specifically for the Ford .874 diameter lifter compared to one ground for a Chevy .842 lifters, not to mention the increased reliability of a larger roller wheel and axle.

My question is, why are you limited to just .680 lift?

Cheers,

Joe
Title: Re: Cam Selection
Post by: Flusher on May 06, 2015, 12:14:50 AM: Quote from: LakesOnly on May 05, 2015, 06:34:12 PM
I'd strongly advise against the hyd roller camshaft.

I keep hearing this. Is this a Ford 385 thing?
Title: Re: Cam Selection
Post by: philofab on May 06, 2015, 06:10:10 AM: Yes, BBF have some odd valve train angles and it causes the pushrods to move side to side a bit through travel. Although a roller cam can be made to work it takes a lot of setup time and is prone to wear out pushrods quickly.
Title: Re: Cam Selection
Post by: fullfam1 on May 06, 2015, 07:56:07 AM: I'm running a roller cam in my 545. no problems just make sure everything is set up correctly, fords don't give any room for error while running hydraulic roller

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Title: Re: Cam Selection
Post by: FRiCK916 on June 06, 2016, 02:27:48 PM: Chris Straub or Kip at Cam motion can set you up sir! An @ .050" 248/256 .600-.650 lift on a 112 should make a nice happy medium for you.