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Offline waldo786

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roller cam?
« on: April 08, 2014, 09:31:34 PM »
Hello all,


    From what I understand a ranger roller cam will bolt into our heads with no problem.  I also found a crane dam that claims excellent low end torque.  I'm looking at making a nice driver out of my Pinto and have an offy 4 bbl intake with a holley 390 carb.  I also have the exhaust manifold from an 88 ranger.  Wondering if this cam will bolt right in as it is a replacement for the ranger roller, and what I might expect.  Also planning on adding stainless swirl polish valves as well. 


http://www.cranecams.com/188-189.pdf




Offline D.R.Ball

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Re: roller cam?
« Reply #1 on: April 08, 2014, 10:23:53 PM »
Just use the Ranger Roller Cam and have fun....The Cranes are for circle track, drag racing etc... Check with Turboford.org etc.

Offline Wittsend

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Re: roller cam?
« Reply #2 on: April 09, 2014, 10:17:31 AM »
The Ranger cam used two different roller rockers.  The earlier rockers fit the valve stem width of the Pinto motors.  The later rockers have too narrow of a guide slot to fit the Pinto valves.  These roller rockers also had two different ratios.  So, you have to match the roller rockers to the valves slot size, then you have to match cam to the rocker ratio.  Simplified just get the cam and the rockers from an early Ranger or Mustang.  Check for yourself, but I think the cut off year for the early rockers is 1993.

The worse case would be to use early rockers with a later cam (if you even can).  Lift would be very low.  Some have speculated using later rockers with an early cam for greater lift. But then you have the guide slot issue.  Discussion on the matter concluded that widening the slot would be difficult to follow the guide contours and have a hardened surface.  BTW, the Ranger/Mustang roller cam actually has a lower lift that a stock Pinto cam.  However, it is speculated that the lift rate (ramp speed) is faster and total volume passing through an open valve cycle is larger.

Offline amc49

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Re: roller cam?
« Reply #3 on: April 09, 2014, 02:52:53 PM »
The problem with the Crane grinds listed there are the same as always for these engines, the lift is too low for the duration. The first lowest choice is already bumping the duration up with almost no increase in lift. I look for at least .060" lift improvement before I even think about another cam, you've got 1/3 that there.  Erson used to make some sticks that used to have say 210 degrees with around .450"-.460" lift and much better cam for these engines. Dunno if they list anything like that anymore and they were more expensive than others. FYI thinking stock lift is around .400" or so.

Offline waldo786

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Re: roller cam?
« Reply #4 on: April 09, 2014, 09:30:04 PM »
Where can I find the specs on a ranger roller cam, and where can I buy one?  Are the ok to buy used say out of a wrecking yard?  These gross lift for the first cam was .420.  I just want a nice cruiser that has a little more power than the stock setup it has now.  Not looking for anything too racy and high rpm.  My goal is to eventually put in an overdrive so I wouldn't be running real high rpms.  I was looking at  top end kit from BoPort that has the springs, retainers, valves, and he also sells the roller rockers.  How can this Crane cam also work with both size rockers and valves as mentioned above as it says it is a replacement for 88 to 98?  This is the first real engine "build" I'm doing so sorry for all the questions.

Offline 74 PintoWagon

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Re: roller cam?
« Reply #5 on: April 09, 2014, 10:13:08 PM »
Art
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Offline Rob3865

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Re: roller cam?
« Reply #6 on: April 09, 2014, 11:28:18 PM »
There's no reason in the world to settle for grinds that are not what you want. I have had Oregon Cam Grinders regrind many camshafts for me and they do a great job.

http://www.oregoncamshaft.com/

Go all the way to the bottom of the page and click on the red square in the center at the bottom and then choose the style grind. You will see all of the grinds they have available. They will grind any grind you see, even mix and match any lift and duration you see and will grind to any lobe separation for 125 dollars for roller grinds. I have one with them right now getting ground for my bobcat's 302. The four cylinder cams may be less, I don't know. The gentleman's name you want to speak to is Ken. He is very helpful.

Offline 74 PintoWagon

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Re: roller cam?
« Reply #7 on: April 09, 2014, 11:45:13 PM »
Thanks for the link Rob, been looking for someone that does custom grinds..
Art
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Offline Rob3865

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Re: roller cam?
« Reply #8 on: April 10, 2014, 12:51:14 AM »
You're certainly welcome. Give Ken a call. He is a super nice guy.

Offline 74 PintoWagon

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Re: roller cam?
« Reply #9 on: April 10, 2014, 07:28:41 AM »
I sure will, thanks.. 8)
Art
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Offline Pinturbo75

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Re: roller cam?
« Reply #10 on: April 10, 2014, 07:50:08 AM »
just an fyi..... the hotrod high story on the cam and different ratio rollers has been 100% proven to be a false theory..... the only place you can get a different ratio roller is from esslinger... and they are pricy.... nearly the price of a new aftermarket cam...all ranger cams have the same lift and profile and the rollers are the same ratio with the difference being the early ones fit 11/32nds valve stems and the late ones fit 7mm valve stems... thats the only difference....
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Offline dick1172762

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Re: roller cam?
« Reply #11 on: April 10, 2014, 08:40:52 AM »
Well there's as many people saying yea as nay. Its all in who you trust I guess. Cam theories is like a~~ holes. Every body has one.
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Offline 74 PintoWagon

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Re: roller cam?
« Reply #12 on: April 10, 2014, 09:09:45 AM »
Cam theories is like a~~ holes. Every body has one.
Ain't that the truth, lol.. ;D
Art
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Offline dick1172762

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Re: roller cam?
« Reply #13 on: April 10, 2014, 09:23:05 AM »
Go to http://www.4m.net/showthread.php?318610-2-3-roller-sliders-rocker-question  Go down to #7 & #8 post to read what Ford printed about the rocker arms.
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Offline 74 PintoWagon

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Re: roller cam?
« Reply #14 on: April 10, 2014, 09:43:50 AM »
Very interesting.
Art
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Offline Pinturbo75

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Re: roller cam?
« Reply #15 on: April 10, 2014, 12:23:56 PM »
its a type-o.... a reputable machine shop affiliated with turbo ford measured both cams and followers and both are the same ratio.... this person also sells them for both early and late model heads and verified they have the same ratio...
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Offline dick1172762

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Re: roller cam?
« Reply #16 on: April 10, 2014, 12:27:34 PM »
Well if its a type-o, its a type-o from FO MO CO
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Offline Rob3865

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Re: roller cam?
« Reply #17 on: April 10, 2014, 03:41:38 PM »
Higher ratio rockers or followers are a useless waste of money. All you have to do is choose a cam grind with the right amount of lift to begin with. Problem solved.

Offline dick1172762

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Re: roller cam?
« Reply #18 on: April 10, 2014, 04:21:00 PM »
But where except a Ranger cam and rocker arms, are you going to get one for under $100? Not everbody is building a race car out of their Pinto.
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Offline Rob3865

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Re: roller cam?
« Reply #19 on: April 10, 2014, 05:30:34 PM »
Did you read my post above? For 125 Oregon Cam will regrind your Ranger cam. It might be less. 125 is what they charge foe a V8 cam. I'm not building anything close to a race engine. 125 for a custom roller regrind is a bargain.

Offline amc49

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Re: roller cam?
« Reply #20 on: April 10, 2014, 09:46:41 PM »
'Higher ratio rockers or followers are a useless waste of money.'

I do not concur. There is an effect that can be achieved by popping open a valve faster in some way than the cam itself will do. For want of a better term I always referred to it as the 'gulp factor', an engine may well want that. For one, it can get flow started faster. That phenomenon can be very handy on engines with lower rod ratios since piston spends less time at the TDC rockover. You get more effective working timing.

I have used them many times and never lost power doing so, the point is, if you have them and a cam, the cam is automatically going to be bigger, are you going to walk away from that? No good tuner will. It is much easier to mix and match rockers than cams if motor already has clearance built in for it.

Often the cam numbers you want can be unobtanium as well. Just because someone grinds to any spec does not mean he can do the heat treat processes needed to make some of those grinds live. I can think of some that would shell pretty quick in a regrind.  I have seen regrinds spit their guts out way more than once and these engines are very hard on rockers and lobes if using the slider type. Sometimes the base circle reduction from regrinding can be a problem as well, if enough lobe to warp the stick with every action. Always better to keep base circle big as possible, less valve to valve variation that way.

Of course no insult intended to your regrinder, he may well do re-heattreat.  Many don't though and regrinding costs you the case hardened outer surface. Not the hot setup, I'll take the bolt on rocker there. That hardening is often only like .010" thick.

Offline 74 PintoWagon

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Re: roller cam?
« Reply #21 on: April 11, 2014, 08:20:32 AM »
Higher ratio rockers or followers are a useless waste of money.
Well, as I mentioned before I've never been a 4 banger person so I don't know, but I can tell ya that in big V8's they make a big difference just by increasing the exhaust, and the clocks don't lie.. ;) :D
Art
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Offline Wittsend

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Re: roller cam?
« Reply #22 on: April 11, 2014, 10:08:24 AM »
This discussion got deep pretty fast. Waldo 786, as to your unanswered question I stated in my post (3rd one) you have to get the right cam.  I did get my cam/rockers out of a wrecking yard.  In my case Pick Your Part at their 50% off sale.  The cam was $12 and the rockers $1 each.  I took the lifters to because at 50 cents each I just couldn't resist.  With all their fees and taxes I was still out the door for under $30.  Maybe it is just "me being me," but I still marked the rockers to make sure they rode on the same cam lobes.

Offline amc49

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Re: roller cam?
« Reply #23 on: April 11, 2014, 08:38:11 PM »
I got that disease as well.......... ............ev en if changing head I like to keep run-in parts together.

Offline Rob3865

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Re: roller cam?
« Reply #24 on: April 11, 2014, 10:17:36 PM »
Ken has been grinding cams over 30 years. I would have agreed with your heat treating assessment before I talked to him. But he told me some very surprising things. He says all of the factory cams are hardened almost all the way to the core. I was surprised to learn that.

Also, the higher ratio rocker doesn't open the valve at any faster rate. Only a different cam lobe can do that. It does however open the valve further, which as I said, can be accomplished by choosing a camshaft with enough lift to begin with.


'Higher ratio rockers or followers are a useless waste of money.'

I do not concur. There is an effect that can be achieved by popping open a valve faster in some way than the cam itself will do. For want of a better term I always referred to it as the 'gulp factor', an engine may well want that. For one, it can get flow started faster. That phenomenon can be very handy on engines with lower rod ratios since piston spends less time at the TDC rockover. You get more effective working timing.

I have used them many times and never lost power doing so, the point is, if you have them and a cam, the cam is automatically going to be bigger, are you going to walk away from that? No good tuner will. It is much easier to mix and match rockers than cams if motor already has clearance built in for it.

Often the cam numbers you want can be unobtanium as well. Just because someone grinds to any spec does not mean he can do the heat treat processes needed to make some of those grinds live. I can think of some that would shell pretty quick in a regrind.  I have seen regrinds spit their guts out way more than once and these engines are very hard on rockers and lobes if using the slider type. Sometimes the base circle reduction from regrinding can be a problem as well, if enough lobe to warp the stick with every action. Always better to keep base circle big as possible, less valve to valve variation that way.

Of course no insult intended to your regrinder, he may well do re-heattreat.  Many don't though and regrinding costs you the case hardened outer surface. Not the hot setup, I'll take the bolt on rocker there. That hardening is often only like .010" thick.

Offline Wittsend

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Re: roller cam?
« Reply #25 on: April 12, 2014, 02:07:50 AM »
"Also, the higher ratio rocker doesn't open the valve at any faster rate."

Theoretically the speed is the same to TDC of the cam (or better said BDC on the OHC 2.3). But the valve is (as you state) lifting it further...  sooner. So to a certain level of lift it is getting there faster.

  Meaning at the same amount of duration the lift on the higher ratio rocker will be higher in comparison to the lift on a "normal" ratio rocker.  So, to a given "lift number" (up to the maximum lift of the normal ratio rocker) the higher ratio rocker is faster to that lift point.

Offline Rob3865

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Re: roller cam?
« Reply #26 on: April 12, 2014, 02:56:58 AM »
Yes, you are correct. My apologies. I should have known this because in order to increase rocker ratio, the pushrod cup has to move closer to the pivot point. Pretty easy to figure out looking at it from that way. Here is a pretty good read on it that I found.

Higher Ratio Rocker Arms

 by Jim Hand, July 1999

 [This article originally appeared on Eric Douthitt's, The Pontiac Garage,
 website. It now appears here courtesy of the author and Eric Douthitt.]

 What are the overall effects of higher ratio rockers? Do they add stress to the engine? Are they safe to use? Do they add power? What precautions should be considered before installing them? The following is a summary addressing these questions.

 The basic valve train consists of a cam, or cam lobe, some sort of cam follower, such as a lifter, a push rod, a rocker arm, and the valve (with the associated retainer/keepers, and valve springs). The cam lobe lift is dictated by the dimension from the base circle of the lobe to the lobe centerline, or peak of the lobe. The base circle must be kept large enough to not degrade the strength of the cam, while allowing for enough lift (in conjunction with the rocker arm) to meet all design goals. Obviously, the peak lift of the lobe cannot be higher then the outer diameter of the cam bearings - otherwise, the cam could not be installed. So, in cam design, as more lift is designed in, the base circle becomes smaller in diameter. As the obtainable lift is limited, the lift is multiplied by the rocker arm ratio to bring it up to the desired point(s). If we used rocker arms that had a 1 to 1 ratio, the valve would follow the exact opening and closing as the cam lobe - same peak lift, same opening and closing rate, and same limited valve open area. By making the rocker some greater ratio, such as the standard 1.5, the lift of the lobe is multiplied by 1.5, the opening and closing rates are much faster, and the area under the overall "curve" is much greater. This becomes very obvious by reviewing the graph.


 The cam is rated at some duration at .050 lifter/tappet rise. This of course cannot be changed and will remain the same regardless of the rocker arm ratio. However, the valve lift is normally specified with standard 1.5 ratio rocker arms. This can be changed by installing different ratio rockers. As a 1.65 ratio rocker is 10% higher ratio then a 1.50, the lift provided by the 1.65 rocker will be 10 % greater with all cams. This also can be seen on the attached graph. Note that the graph shows a 1.72 ratio rocker, but the action is similar between various ratios. What happens to valve open time with the higher ratio rockers? Because the higher ratio rocker lifts the valve to a higher point in the same time period, it has to lift both quicker and steeper. As the valve begins to open at the same point regardless of rocker ratio, and it opens at the same time as the cam lobe, the duration of the valve opening in crankshaft degrees at the initial opening and closing points is identical to the cam lobe duration. However, because of the quicker and steeper opening/closing rates, the valve open time is greater from any point after initial opening when a higher ratio rocker is used. This is also obvious on the graph. How much more duration? I devised a method to actually measure it. As a standard lobe measuring point is .050 lifter rise, and lobe lifts are normally specified with 1.5 rocker ratio, that means the valve will always be at .075 when the lobe reaches .050" lift (when a 1.5 rocker is installed). By using the .075 point, and determining where it occurs in relationship to the crank in degrees, a yardstick is provided from which to reference any different rocker ratios. As expected, a higher ratio rocker will allow the valve to reach the .075 lift point earlier in the lift cycle (and later in the closing cycle). As the .075 valve lift point is the industry standard when specifying cam duration (1.5 standard rocker ratio X .050 tappet/lifter rise), it becomes a valid reference point. In the Wolverine 234 degree intake lobe, the intake valve was open 4 to 5 degrees longer when measured in reference to the crank when the larger ratio rockers were used. This is also easy to see on the graph.

 Summary:

 Higher ratio rocker arms open the valve faster, higher, and hold it open for a much greater total period of time as compared to lower ratio units. Does this cause more stress on the valve train? There will be more pressure on the cam lobes due to the friction and pressure caused by the higher lift and resultant greater spring load. However, as compared to providing the same higher lift and effective longer duration with a more radical cam and even stiffer springs, the higher ratio rockers may create less total valve train stress. And such a cam lobe would be very aggressive and would require much heavier springs to keep the lifter from flying off the lobe. Very radical lobes will also add more side stress on the lifters/bores and could possibly cause lifter bore failure. The added pressure on the studs from either higher ratio rockers, or more radical lobe, will be well within the capabilities of modern after market studs.

Offline amc49

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Re: roller cam?
« Reply #27 on: April 12, 2014, 04:08:49 AM »
So much for that. Also, you don't harden a cam all the way to the core, rather, you pick a base material of the raw part that is as hard as you want it. Problem with that is, when making thousands of them it will cost you millions more in tooling costs, so you harden the outer surface after machining it while softer. It rarely is more than a few thousandths thick. .100" is a bunch there.

Offline dick1172762

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Re: roller cam?
« Reply #28 on: April 12, 2014, 08:22:06 AM »
Thank you rob3865! Maybe this will put an end to this thread and just show that if you could or would machine a late model 2300 roller rocker arm to work on an early cam, it would be ok. I doubt any of us will do so, but it can be done. And why not turn the tip of the valve down to fit the rocker arm?
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Re: roller cam?
« Reply #29 on: April 12, 2014, 12:03:39 PM »
That is a well written article. It is obviously written from an OHV/ Cam in Block or one piece bearing, OHC perspective.

  The only point I'd disagree with is, "Obviously, the peak lift of the lobe cannot be higher then the outer diameter of the cam bearings - otherwise, the cam could not be installed."  Many modern OHC engines use a split bearing similar to a crankshaft. So, there is no "pass through" restriction of cam bearing size.  Again, I realize the engine type he is referring to in the article. I just didn'twant anyone to think that was a restriction for all engines.

BTW, for higher lift on "in block" designs do they ever go to larger cam bearings?