Author Topic: Cam question for a stroker FE  (Read 804 times)

Side-Oilers

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Cam question for a stroker FE
« on: February 13, 2019, 12:28:24 AM »
The aluminum stroker FE (482 cubes) in my Kirkham 427 just ate a rocker arm, which in turn messed up the pushrod and cam, of course.

Now trying to figure out the best cam to put in her.

It had a solid lifter conventional cam. I'm thinking about changing to a roller hydraulic like is in my KR. Can't put my hands on those cam specs for the KR, though, so does anyone have a favorite?

My goal is tons of torque from idle to 5000 rpm or so, and a 6000 rpm redline.  Big hp numbers aren't as important, for me, but I'd think with all those cubes I could feasibly get 550-575 hp with the 10.5 compression I'm running.  That's what the solid lifter setup made.

The engine is a Genesis block with Edelbrock heads and a single Holley. 3.54 rear end gears.  TKO 5-speed.

Most use is on the street, but it sees Willow Springs track use twice a year. 

Any and all suggestions are appreciated.  Thanks!

Did I mention that I love torque?

« Last Edit: February 13, 2019, 12:46:01 AM by Side-Oilers »
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vtgt500

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Re: Cam question for a stroker FE
« Reply #1 on: February 13, 2019, 07:53:46 AM »
I'm running a well modified, dual quad side oiler that's been flawless for many years.  Using a 294S cam, shell lifters, with Edlebrock heads, Dove rockers and rocker shafts, but would not begin to offer recommendation for best, current choice, especially with a stroker crank.  There are a couple FE boards with competent builders that contribute.  Unfortunately, are dozens of goobers contributing as well.  Do some homework and you'll get your answer.  Curious, what brand of rocker failed on you?
« Last Edit: February 13, 2019, 11:57:13 AM by vtgt500 »

Side-Oilers

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Re: Cam question for a stroker FE
« Reply #2 on: February 13, 2019, 10:04:24 PM »
Thanks, vtgt500. I have looked at the FE boards, and have some ideas, but still want to put the question in front of all the SAAC FE guys.

The engine was in my Kirkham when I bought it, so I don't know for sure on the brand of rockers. 
Any clue from the pix?

 
« Last Edit: February 13, 2019, 10:08:02 PM by Side-Oilers »
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tesgt350

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Re: Cam question for a stroker FE
« Reply #3 on: February 14, 2019, 07:13:00 AM »
If I remember right, my 1970 428CJ Mach 1 ran a 292 Duration & 694 Lift.  I was running 13.1 Compression Forged Pop Up Pistons. 
« Last Edit: February 15, 2019, 09:14:20 AM by tesgt350 »

vtgt500

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Re: Cam question for a stroker FE
« Reply #4 on: February 14, 2019, 07:24:42 AM »
Ouch.  I don't recognize your rocker set up.  Resembles my Dove product, but spacers and end stands appear different.  I have heard good reports on Precision Oil Pump rockers.  The Jesel product is probably the best and has a price tag to match.  Some inexpensive Chinese import being privately labeled.  If you do a teardown carefully inspect the rocker shaft.  Mine were gun drilled with horrible burrs at cross hole intersections.  Using an aircraft length reamer removed most of the burrs.  Then used Flex Hones to develop an edge break at the cross holes.  Had a burr broke loose, possible to have caused a similar failure.  As there is no room for a bearing on the shaft journal, size and surface finish is super critical.  I micro polished my shafts with lapping film to a mirror finish, then coated with Dicronite.  Result is almost frictionless.  Again, I have limited, first hand experience with alternate product.
http://dovemanufacturing.com/ford_352_428_fe.html

shelbydoug

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Re: Cam question for a stroker FE
« Reply #5 on: February 14, 2019, 07:55:40 AM »
They might be the Ford Power Parts set up. I had a set of those. They pre-dated the Dove which are similar. The only thing with the FPP items is that often the anodized color could vary. I'm sure that those are FPP shaft spacers. Other manufacturers parts often are very similar.

One data fact that I remember but I see rarely mentioned is that aluminum rocker arms have a very finite fatigue factor. Stainless arms do better. Compcams talks about that on their web page.

When you use aluminum arms you want to start with a set that has zero hours on them, so if you purchase a used set you are working with an unknown and could be close to the end. They do break and race teams do replace them regularly on a "running hours" basis. They keep an engine part log book (or should).

427heaven

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Re: Cam question for a stroker FE
« Reply #6 on: February 14, 2019, 09:52:08 AM »
This is THE most complicated question to answer when building your engine. First off you will need to consult with your engine builder he will be one to help hit the sweet spot. It doesn't matter if your engine has 700+ plus cubic inches or a stock 352 you want to run, what you have to remember is ALL of the valve train components have to compliment each other this is where most people go sideways. For starters Aluminum rockers are not daily street driven components, occasionally good- regularly not good. Bigger cams require more spring pressure no aluminum in this equation. To the average guy a good hydraulic cam is all that's needed, if you are looking for max performance a nasty solid cam might light your fire as it does me, but you need to work on your car occasionally for normal adjustments, next will be a hydraulic roller or solid roller ,these are not for most of us but OHHH BAAABY do they sound and run GREAT! I run those in some of my other cars. It all depends on your wallet, skills, usage etc. Good Luck on your choice. ;)

68stangcjfb

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Re: Cam question for a stroker FE
« Reply #7 on: February 14, 2019, 11:49:09 AM »
Side-Oilers, do you know the lift of the cam you have? When I was young and dumb, I was running the Dove standard rockers and end stands with a Crane .587 lift solid cam and an Edelbrock F4B intake. I never broke a rocker arm but I have a drawer full of bent pushrods (some of which I had to pull out with visegrips) that I finally figured out was being caused by the pushrods rubbing the holes in the intake. I opened the holes in the intake up with a larger drill bit and solved the problem. I noticed the holes in your intake look standard size. With high-lift cams, you have to make sure there's clearance for the pushrods. At high RPM, the sideload on the pushrod is pushing the rocker as well. It may not be your problem but it's one more thing to check.
« Last Edit: February 14, 2019, 12:08:11 PM by 68stangcjfb »
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Side-Oilers

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Re: Cam question for a stroker FE
« Reply #8 on: February 14, 2019, 05:41:52 PM »
Ouch.  I don't recognize your rocker set up.  Resembles my Dove product, but spacers and end stands appear different.  I have heard good reports on Precision Oil Pump rockers.  The Jesel product is probably the best and has a price tag to match.  Some inexpensive Chinese import being privately labeled.  If you do a teardown carefully inspect the rocker shaft.  Mine were gun drilled with horrible burrs at cross hole intersections.  Using an aircraft length reamer removed most of the burrs.  Then used Flex Hones to develop an edge break at the cross holes.  Had a burr broke loose, possible to have caused a similar failure.  As there is no room for a bearing on the shaft journal, size and surface finish is super critical.  I micro polished my shafts with lapping film to a mirror finish, then coated with Dicronite.  Result is almost frictionless.  Again, I have limited, first hand experience with alternate product.
http://dovemanufacturing.com/ford_352_428_fe.html

Thanks for the info. The inside of the engine looks clean and well put together, but obviously SOMETHING caused the problem.  It happened at Willow Springs, but the engine was running "perfectly" right before. (Famous last words.) 

I never took it over 5500 rpm.  But, in a stroker, I know that's the upper limit if you want it to live.  I usually short shift around 4500-5000.

I'm definitely considering using Jesel or Dove parts.
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Side-Oilers

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Re: Cam question for a stroker FE
« Reply #9 on: February 14, 2019, 05:44:51 PM »
They might be the Ford Power Parts set up. I had a set of those. They pre-dated the Dove which are similar. The only thing with the FPP items is that often the anodized color could vary. I'm sure that those are FPP shaft spacers. Other manufacturers parts often are very similar.

One data fact that I remember but I see rarely mentioned is that aluminum rocker arms have a very finite fatigue factor. Stainless arms do better. Compcams talks about that on their web page.

When you use aluminum arms you want to start with a set that has zero hours on them, so if you purchase a used set you are working with an unknown and could be close to the end. They do break and race teams do replace them regularly on a "running hours" basis. They keep an engine part log book (or should).

Thanks Doug, that all makes sense.  Good point about the fatigue point on aluminum rockers.  I will change everything in the valvetrain.
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Side-Oilers

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Re: Cam question for a stroker FE
« Reply #10 on: February 14, 2019, 05:50:54 PM »
This is THE most complicated question to answer when building your engine. First off you will need to consult with your engine builder he will be one to help hit the sweet spot. It doesn't matter if your engine has 700+ plus cubic inches or a stock 352 you want to run, what you have to remember is ALL of the valve train components have to compliment each other this is where most people go sideways. For starters Aluminum rockers are not daily street driven components, occasionally good- regularly not good. Bigger cams require more spring pressure no aluminum in this equation. To the average guy a good hydraulic cam is all that's needed, if you are looking for max performance a nasty solid cam might light your fire as it does me, but you need to work on your car occasionally for normal adjustments, next will be a hydraulic roller or solid roller ,these are not for most of us but OHHH BAAABY do they sound and run GREAT! I run those in some of my other cars. It all depends on your wallet, skills, usage etc. Good Luck on your choice. ;)

Thanks for the info. I like the hydraulic roller in my KR's 468-inch Shelby Engine Company mill.  Need to dig up that info.  Denbeste, who built it, doesn't tend to post their cam specs anywhere online.  Good point on the spring pressure.  My engine guy says the old springs were too soft for that cam. I never got it into valve float, but who knows what the previous owner may have done.
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Re: Cam question for a stroker FE
« Reply #11 on: February 14, 2019, 05:53:53 PM »
Side-Oilers, do you know the lift of the cam you have? When I was young and dumb, I was running the Dove standard rockers and end stands with a Crane .587 lift solid cam and an Edelbrock F4B intake. I never broke a rocker arm but I have a drawer full of bent pushrods (some of which I had to pull out with visegrips) that I finally figured out was being caused by the pushrods rubbing the holes in the intake. I opened the holes in the intake up with a larger drill bit and solved the problem. I noticed the holes in your intake look standard size. With high-lift cams, you have to make sure there's clearance for the pushrods. At high RPM, the sideload on the pushrod is pushing the rocker as well. It may not be your problem but it's one more thing to check.

Good tip, thanks. I have seen an FE with that rubbing problem. I will ask my engine guy to open those clearances up at bit.
« Last Edit: February 14, 2019, 05:57:19 PM by Side-Oilers »
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Re: Cam question for a stroker FE
« Reply #12 on: February 14, 2019, 06:10:25 PM »
The end stands, stands and spacers are a Precision oil pumps products. The roller rocker's weak point is the bushing thins the rocker to a point they are weak and break under high lift/ heavy spring loads.  I have Doug's end stands, spacers, rocker shafts and Dove forged roller rockers in my Shelby with Isky 3/8 molly pushrods.
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1967 eight barrel

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Re: Cam question for a stroker FE
« Reply #13 on: February 14, 2019, 06:13:58 PM »
P.S. Barry Robotnic would be the one to contact at Survival Motorsports in Michigan about your cam.

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Side-Oilers

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Re: Cam question for a stroker FE
« Reply #14 on: February 14, 2019, 06:16:42 PM »
The end stands, stands and spacers are a Precision oil pumps products. The roller rocker's weak point is the bushing thins the rocker to a point they are weak and break under high lift/ heavy spring loads.  I have Doug's end stands, spacers, rocker shafts and Dove forged roller rockers in my Shelby with Isky 3/8 molly pushrods.
                                                                                         -Keith

Thanks for the parts identification, Keith.  I know not to buy those again. 

Van

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