billet vs non billet cam

A

aksparkey01

bombing addict.
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Mar 31, 2008
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alright, just read through a good 30 page post about cams. I was hoping to get a few oppinions about when billet is required or recomended. Im leaning twards a helix cam, i wont be turning over 4k and will be looking to move arround 500-525 cc with a 12mm p pump(hoping 750-800hp with twins) what cc's or rpm would you guys reccomend a billet cam? BTW this is a mostly street driven truck.
 
there are two reason i can think of to go billet.

1st an 13mm pump running 650+cc's and turning 4500+ rpm. although if you dont have any shock load situations even then youll prolly be alright until the drivline breaks or you snap out of the throttle

and 2nd when you are looking to put a really large profile on the cam. on a cast regrind by the time you change the lobe seperation angle and then grind more off the base circle for more lift and duration the lobe is much to triangular on the nose. where as with an round lobe blank you can put any profile you want on it.

a good street profile will fit just fine on a regrind but an agressive ramp rate large lift cam needs a round lobe blank to start with to fit
 
I would not run a steel billet cam, in any application where longevity is the goal; the lobes will wear a lot quicker than a cast factory cam. The advantage is the possible extreme profiles; you can go to on these cams with reduced base circle barrels. The cast cam with base circle reduction , made necessary by high lobe lifts will detract from rigidity. The lift is not an advantage if the head is not ported to flow air in the range of lift. A stock Cummins head 24 valve head stalls out at about .350 lift. You can lift the valve to the moon and not gain any more flow without carful valve job considerations.
Now if you go and port the head, do an infinite angle blended valve job, with the proper angles, the head will extend flow number to .600.


On a Common rail there is no strength issues , so a good cam with about .275 to .290 lobe lift on the intake and .300 to .325 lobe lift on the exhaust will make all the power possible with an un ported head.
With your 12 valve these number work as well with the increased rocker ratios.



If you are going to work the ports then .375 lobe lift on the intake and .350 lobe lift on the exhaust work
 
well, i was more worried about breaking the stock cam. I dont have any port/polish work done, but i do have back cut valves and 5 angle seats. Not sure if they do much without a port polish job on a 12v. Just upgrading power and would hate to have the cam break on me, or the gear come off.
 
you wil be fine with any street cam thats a regrind you only need a billet cam if you plan on turning the rpms no need to spend the money in a daily driver
 
my truck is a daily driver somewhat, its a toy as i have 3 other trucks anyways, i am running a 13mm pump with twins and running 4500 rpms and above, anyways, what cam would you recommend for my situation, i am changing too a s300 over a s480 twin kit probably, gonna be running super dragon flow injectors and a 650cc pump. Thanks alot its a 97 12v.
 
COMP461 said:
I would not run a steel billet cam, in any application where longevity is the goal; the lobes will wear a lot quicker than a cast factory cam.
Click to expand...


Ok, I've got and 05 CR and am gonna be running the F1 Billet Steel 8620 H2 cam.....I've had cam bushing installed in all 7 journals of the block..

Why else would I have a long term longevity issue with this engine after my build....

Don does recommend the ZDDP additive to be run at all times!! Will this cure the longevity issues??

What else do I need to know here!! I don't wanna be building this thing again for several years to come....My dang wallet won't take much more!! LOL
 
If you’re going to go to the trouble to run a billet cam, why run something that small.

Second in a CR its not even close to needing that core. The pump uses a straight cut gear, and requires very little hp to turn, without the pulses a p pump impart in to the gear train. Bigger is not always better , and if you don’t have the head to support big lifts , then you wasting money use a standard H2 is your going to use Don’s cams.


If you’re going for a ultimate unlimited type engine then by all means, but do a cylinder head with intake, and a ring package along with the other parameters involved in it. Otherwise on a street truck be realistic in your parts list, don’t use 1300 hp parts on a truck that will never be used as a dyno queen, sled puller ,or drag racer.


I do billet cans as well, and I would never put one in a truck that is going to see 100,000 miles , or even 25,000 miles even with additive. I have over 100 of these billet cams out there in pullers, and drag racers, and no problem, but these are all competition machines.
 
COMP461 said:
I do billet cans as well, and I would never put one in a truck that is going to see 100,000 miles , or even 25,000 miles even with additive. I have over 100 of these billet cams out there in pullers, and drag racers, and no problem, but these are all competition machines.
Click to expand...



So what exactly are you saying???

Is my newly built engine gonna take a big CHIT after 20K-50K miles or something.....????? What's it gonna do??? Exactly??

The Billet cam and Processed Tappets are already here and about to go in.....

Anybody else here think this is a bad idea????
 
aksparkey01 said:
well, i was more worried about breaking the stock cam. I dont have any port/polish work done, but i do have back cut valves and 5 angle seats. Not sure if they do much without a port polish job on a 12v. Just upgrading power and would hate to have the cam break on me, or the gear come off.
Click to expand...


I dont like using a Helix 2 casting in a P pump application. We have 100 plus of these in 12 valves now that I know of and 2 have broken. 2% is getting higher than I like so I suggest a billet steel cam with a bolt on gear set-up.

On the other hand, some guys are running the cast H2 cam ( myself included ) with a radical 13mm P pump and turning 5000 RPM plus. IMO, its a matter of time before I break this cam in 3 pieces.:doh: I plan in slipping in a drop-in billet in the next few weeks to avoid that.

The good thing about the Helix bolt-on system is that in the event of a broken cam, the damage is reserved to bent valves, push tubes and perhaps the pistons get kissed. A press on style cam will break in the right place and allow chunks ending up in the rotating assembly. Taking out the rods and perhaps the block.

Billet cams can be successfully run for the life of the engine
 
I didn't think Don would make or suggest something that wouldn't last!!!

Thanks Don for clearing that up....I look forward to see what this thng will do....
 
I have had a couple of people send in 8620 billets cams with treated billet tappets in the last month. I know one guy used top notch Brad Penn oil with zinc additives. I believe they had less 5000 miles. The cam and the tappets were worn so bad that they were unusable. Don, didn't you originally say no additives were necessary and that the block did not have to be line bored? Why the change all the sudden?

I see Don and Greg have posted, now if we can get Fletch to post a couple OMG's, this will officially be a pissing match.

Aksparkey- All B.S. aside, I have never seen a high mileage steel billet cam. That is why don is now preaching cam bushings and zddp additive where before it was said they were not needed. I wouldn't say it can't be done, just that traditional wisdom would say it is another thing to worry about. If you used roller tappets it would be a different story. If you want to run it, after a 1000 miles check lash to see if they are starting to eat each other yet. After 10,000 miles I would bar the engine over and measure lift with a dial indicator reading off of the pushrod. Best wishes and good luck with whatever you choose.

Zach
 
Zack, What would you suggest someone use in a pulling Truck with a big pump? The cast ones seem to break and the billet ones don't sound good from your post.
 
Thanks for the input guys, I wasnt planning on swapping my cam really soon. I was thinking that it would be good to have one on hand next time i tear in to the motor. I fixed a broken timing case last year because of kdp and am pretty pi**ed at my self for putting the stocker back in. My truck might see the track twice a year and other than that it a dd. After alot of reading and your help i think i will go without the billet. Don, would you say that the helix is stronger that a stock cam?
 
Jerrod, billets aren't necessarily a bad thing unless they are marketed to daily drivers as unbreakable. If you are competition only I would run one. The problem is if you are competition only then the street profile on the h2 will put you at a disadvantage to others that have much wilder profiles on their billets. Be sure to run additives like nitrolube or zddp. Rollers seem to do better with 8620 cores than flat tappets.



Zach
 
U dont have to have a billet cam, ive broken a Helix with a 13mm pump well....... scratch that it was supposed to be a 13mm but the shop that did it for me stole the parts from my 12mm and put them in his 13mm and then sold it to me and gave me my 12mm back with missing parts and this ummm he'll never know look on his face and told me he couldnt work on my truck anymore. But thats besides the point, Cams are gonna break and wear down, Ive seen stocks with new grinds pull over 5500 with 800cc 13mm and live just fine, Just before you choose a cam wether it be, Hamilton, F1, Greg's, or Diesel Pro's whoever talk to the owners first you will be amazed at what you learn or what you dont learn.
 
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