cam specs?

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I was wondering if anyone new the specs for the sealed power cam # cs 415? Im going to be using this cam and I need to determine where to set it. I have heard 4 degrees advanced. But, I just want to make sure. The engine is from/for a 78 Scout II 345/727/d20/4.56s/35s and is at the machinists. It is being bored .03 over and zero decked. The distributor is an electronic prestolite # 484778c91 idn 4002b 417. Im currently looking at ignition boxes and coils to upgrade the ignition. Im using silvolite pistons and felpro gaskets. The compression will be real close to 9 to 1 so im not sure weather to run reg or mid grade. I need to determine cam specs, what to degree it to and what type of fuel to run before I should place my order to ihon for a Holley side hung 2300 carb. If fuel type comes down to preferences then I prefer to run mid grade if it would pay off power wise.
 
Sealed power cs-415 crosses to the clevite 229-1415 they are both stock replacement cams.
Clevite 229-1415 has the following specs:

duration @ .050 lobe lift (intake): 188*
duration @ .050 lobe lift (exhaust): 178*
valve timing @ .050 lobe lift (intake opens): 17* atdc
Valve timing @ .050 lobe lift (intake closes): 25* abdc
valve timing @ .050 lobe lift (exhaust opens): 19* bbdc
valve timing @ .050 lobe lift (exhaust closes): 21* btdc

the above cam data was from Jesse b. And is for the cam you are asking about. The full part number is 229-1415 from clevite.


Install the cam at the intake valve event I highlighted in red. Don't advance the cam any further. The cam is really very small and doesn't require advancing with 9-1 compression.

With this cam to be using with 9-1. You won't be able to run regular 87 octane, you will need to run mid grade 89 minimum at sea level but above 2500 feet you could run 87.

The increase in compression won't require any jetting changes if it was ok before, only an improvement in octane. If you are unsure go up in main jet .005. For safe measure while you break in the new engine.

one real important item you need to address when you increase compression is the fact that you will generate more combustion chamber heat. The top compression ring needs to have a larger end gap like to .016 - .018" minimum. To accommodate the higher running temps. The engine builder must not skip this step.
 
Thank you Robert, I never would have thought to file the rings, you probably saved me from alot of greif because the machinist didn't mention that yet. It says "crosses over". Does that mean they are the same cams sold under different names, or that they are just very simular. I ask because I need the specs for ihon to set up the carb.
 
The 2 cams for all intents and pourposes are the same +/- 2 degrees. Both are oem replacement cams and will mimic each other in your engine. The tune up won't change at all if you run the midgrade fuel and keep the total ignition to spec. Actualy the cam should be fine with the stock jetting / timing etc.

Do you own the cam yet?
 
I do own the cam, I bought it long ago for this build, when I was planing on just rebuilding it. If I had the money id like to use a performance cam and springs. I May change the cam and springs at a later date, and go to a 4bbl. Or leave it alone and swap in my wide t-19. But I dont have the money or patience right now. Did you see my thread about the roller rockers? I read elsewhere about the advantages of high ratio rockers. But I dont know how they would affect my 2 bbl motor with a stock-ish cam, and no porting. Thanks again Robert.
 
I hear ya on money. I think everybody needs to be a bit cautious.

Increasing the rocker ratio is a good way to get a flat tappet cam to behave almost like a roller cam. The higher valve lifting velocities will give you the big peak torque numbers with little increase in the point at which it peaks. Your IH has a fairly high rocker ratio already at between 1.6-1.7-1. Going higher will require more spring pressure and I would recommend utilizing a comp beehive spring at that point. In fact the benefits of the beehive are much more important on a flat tappet cam because you can lower the peak open spring pressure 15% over a standard spring. That will help reduce cam failures..

For your build and cam I would stay where you are now and go easy on springs. Say 80-90# max seat pressure. No need to go any higher unless putting a bigger cam in the motor for a higher rpm power band.

A roller rockers arms have definite benefits on a high spring force application but on a basically stock build it is a wast of money imo.
 
So I was looking through my parts and I relized that the cam kit I got from northern auto parts came with a sealed power cam and clevite liters and timing set. Is it okay to mix the cam and lifters from different manufacturers? Ive also read about johnson lifters. Is it okay to use the lifters I have? And do you know how cleite liters perform compared to johnsons? Also, what is the stock seat pressure? Thanks again for your time, and sorry I took so long to respond.
 
In the carparts bizz...no oem-replacement "brand name" has much value or really means anything anymore! I know..."how does a diy'er know this"? By coming to forums such as ihon where we know shit!

The clevite "brand" lifters are a johnson product that is simply a private label operation. Rest assured! An example of that is the lifter inventory here at ihon currently. We know the source of these parts as to root manufacture and we know that the johnson product is "correct" both by doing the research/validation and performing a full diagnostics on the issue! For instance...re-visit Robert's lifter tale here:

http://www.forums.IHPartsAmerica.com/gas-engine-tech/965-odd-lifter-wear-pattern-152-a.html

The umbrella holding corporations "behind" all the brand names are constantly changing/melding/disappearing and undergoing selloffs and name change. It's always been that way. Over the last 36 months there has been a shakeout in the car parts supply industry of huge magnitude...and many "brand names" are just that, they are not manufactured by the brand as such as they May have been 10>15 years ago when the name meant something.

The "oem replacement" camshaft deal is the same thing. To be labeled as such, the specs/base quality must fall within the parameters of the oem part. In the case of "oem replacement" parts, such as the lifters, cam, timing gears, etc. All those parts are compatible design/engineering-wise.

Here at ihon we don't deal with hinkeedinkee budget-price engine components (or any other parts!!). The rep here is built on quality and customer service (and this forum is a major part of customer service) and we'd never risk that rep by dealing in parts that are not correct for the application. I assure you, a bunch of verification work went into just selecting the replacement hydraulic lifters to inventory that you find in the online store!
 
It is fine to run those lifters on your sp cam. There are only 2 manufacturers for the IH sv lifter, johnson and ?(can't remember). Everybody sources from either of those two and stamps their name on the box.

If the lifter face looks like it is swirl polished it is a johnson, if it is a dark Matt finish it is the other. My personal favorite is the johnson but really if the lube system of the engine is in good order either is fine.

The stock seat pressures are 60 pounds. I recommend staying between that and 70 pounds. And the open of 180-190 max.

Oem valve spring specs are: book
free length = 2.065"
test pressure= 188#
test length = 1.429"


calculated
Deflection @ test = .636"
spring rate = (188#/.636) 295.6 lb/inch
installed height = 1.865
installed deflection= .2"
installed pressure = (295.6 x .2) 60 lb (seat pressure)

intake open pressure @ .440 = 189.2 lb
exhaust open pressure @ .395 = 175.9 lb

the numbers I listed in red Are from the factory spec book
the numbers in black Are calculated from the book numbers and measured installed heights.
 
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Thanks Robert, I had planned on using the springs I had, if they were still good. How do you increase seat pressure, shims? Or do I need new springs? I didn't make it to the machinist's today, so forgive me for asking.
 
thanks Robert, I had planned on using the springs I had, if they were still good. How do you increase seat pressure, shims? Or do I need new springs? I didn't make it to the machinist's today, so forgive me for asking.

If the springs you were going to use are old and the free length s close they May be ok. Bad thing about old springs is that they don't necessarily give any indication they are about to break. :icon_eek:
valve springs have a finite life and do fail/break at the end.
Cheap insurance and I change them anytime I rebuild an engine that has more than 100k miles on it.

If you would like to use them have the shop check the pressure at the test length I listed above. The book tolerance is +/- 8 #.
If the force measures good you could reuse them.

188lb @ 1.429"

as for setting the seat pressure, yes shiming is how to set that. Shim are useally availible in .025, .032 and ,.050 etc. The machine shop will have them.

Have fun with your project.
 
Thank you Robert, I finally dropped off some parts at the machinists today. He wasn't in though so ill call him tomarrow about cam placment.
 
Ive been calling the machinist daily leaving messages. Since it has taken so long, I can now afford a cam and springs. I think I want the isky 190125-26 and comp cams springs.
 
If you run it zero deck for 9-1 you will have a nice set-up.

I recommend installing the cam 4 degrees advanced at 106 degree intake lobe centerline(your builder will know) to reinforce the low end torque. I would need to see the cam card to determine if the cam is ground advanced. Still needs to be degreed.

The springs are fine and I would install them between 1.825" for 70# seat and 1.800 for 77# seat. The spring has a healthy spring rate of 321#/inch to work with the bigger cam so you don't need supper high seat pressures.
 
Thanks Robert, the cam says 1800 -5000 rpm, but do you think the springs can handle 5000 rpm? What do you think it would be safe to rev to? What about cruizing rpm's, how high sustained? This is after I break it in ofcourse.
 
thanks Robert, the cam says 1800 -5000 rpm, but do you think the springs can handle 5000 rpm? What do you think it would be safe to rev to? What about cruizing rpm's, how high sustained? This is after I break it in ofcourse.

Advancing the cam will shift the torque curve back 200 rpm so the basic rpm range will be 1600-4800 but due to the larger lift the curve will be bigger.

The springs will handle a sustained 4800 rpm. Play it safe and set the springs up at 1.800/77# seat. Sounds like you will use the rpm regularly.

Make sure you have everything balanced.
Can you take a picture of one of your connecting rods?

Defiantly upgrade the rod bolts and follow the bolt manufacturers installation note exactly including recommended thread lubricant( usually a special gray moly grease).

I don't know if Jeff sells an arp alternate rod bolt but if not I'll recommend one.
 
I just bought nos 216114r21 rods, they had a little surface rust so, the machinist May hone em after cleaning em. But 360 for 8 isnt bad. Balancing is somthing else I havent considered. I was going to install the pistons myself, but do you have an idea of how much more balancing would run? I dont plan on running it very high alot, mostly shifts. I was used to doing 70 mph top speed before and I probably wont push it too much further than that. But 4800 rpm sustained sounds awsome. I can see how it would need to be balanced.
 
Ball park for a good balancing job on a v8 is $175.00 if it is close to start with.
New rods don't need to be machined only checked.

Woulds still like to see a picture of a rod. There are a few old versions that I would not recomend running hard.
 
Re balancing -- I have no idea of the cost these days.

The cost will depend on "how far" you want to go... Like pulling the crankshaft and polishing / balancing it (along with the flywheel and crankshaft pulley)...??? Not really necessary, I think, but ....

But, you need to find someone who really knows how to balance an engine - not just Joe at the machine shop who "does it" once in a while...

Maybe robertk / Jeff knows someone to use --
 
The machinist charges $45 hr. And he May have already pressed the piston pins. Ive been trying to get in touch with him.
 
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