If I had a cam choice here is how I would make it.... If I wanted to get one for the cheepest I would go with Piers... If cost wasnt that much of a factor and I wanted the best without changing out pistons I would go with Diesel Dynamics... If I wanted the absolute best I would get a high lift Billet cam with Fly cut pistons. Just my opinion.

Horace

 

[glow=red,2,300]PDR camshaft used here[/glow] ;D ;D ;D

 

Piers Cam is a stock 24 valve that is reground. It retains the press on gear that Cummins uses for its lower HP engines ( 300HP and down ) The marine engines up to 300HP use the press on gear. Once the power is stepped up to 315HP on the marines, the bolt on gear style gear is used. Much of this was to deal with harmonics and vibrations that cause the cam gears to walk off the end of the cam with higher rpm and the load of the P pump at full rack. The stock 24 valve engines many of you guys have was governed to 2700-2800 rpm via software in the VP-44. The VP-44 does not have the same parasitic drag the P pump does. This helps to keep things together. Fueling boxes, big injectors, twins, etc all help the 24 valve engine to rev higher. I see them go 3800 rpm now easily.

Diesel Dynamics uses a new marine cam with the bolt on gear. This cam is made from high nickle content chilled ductile iron and has been shot-peened behind the number 1 bearing journal ( where stress cracks happen and cause breakage ) The bolt that holds the gear on the cam goes to the number 2 bearing journal. This helps to tie everything together in the known trouble spots.

Last year when this was a hot topic I was told that the stock cams do not break and there was nothing to worry about by some. I had seen them break behind number one and had a few friends spin the gear off at higher rpm so I knew it was just a matter of time. At May Madness this year, Mark Kendrick broke a camshaft while hot-rodding around Vegas. Although I did not ask where the stick broke....Im pretty sure it was behind bearing number 1. When he told me the rocker arms behind number 1 were not moving. I knew the cam had broken.

His truck was a P pumped version though. The load the P puts on things really seems to be a partial cause of the broken cams. He rpms his truck high as well.

IMO most do not need an aftermarket cam until they get to 500HP plus. The stock 24 valve grind is not that bad to this level. Once we go higher in power and fuel I feel they are helpful.

Both cams seem to aid in power, EGT reduction, and help spool up. Price wise the Piers cam is less bucks. The DD cam has more cost in pats alone than Piers charges for the entire cam Cummins can have the thumbs down for that one. They dont give away marine parts.

Nathan Wright uses the Piers cam and has had good results with it. I have some dyno and comparitive evidence that suggests it is helping. The breakage issue with stock cams has been discussed and is a concern at his current HP level.


Anything you can do to lighten the valve train is a good thing... i.e. the titanium retainers, etc. One must be careful when using titanium components for everyday use. Most will agree that they are not a long term component. In my case I would use them. ( not driving many miles per year, etc. ) Long haul guys that tow and drive a bunch should stay with the stock retainers and collets or use another material. All out performance is tops with titanium, just not long term. Although this informantion is a few years old and alloys are changing like I change socks...it may now be possible.

Don~

 

Well put Don and Horace.... Since I am not a Mechanic and I have to pay labor I am thinking I should go with a stronger cam... Do it right the first time...

Somehow I knew there was some info coming out from Don!

James

 

Don what do you know about enterprise engine performance cams?Im going out there at the end of september to have my block o ringed & will have them install one of there cams while its apart.Kurt.

 

Hi Kurt,

I dont have a drop of info on the EE camshafts, except I know they have several different grinds and even a billet stick. I have spoken with their cam grinder in the past and he was more than competent on the subject. This was before EE used him.

For any application I would ask for dyno graphs, race track results, etc. This is the best way to compare.

With me, as will always be the case...I rely on the dyno to show me a loss or gain. Of course drivability and durability is factored as well.

So many factors are involved in camshaft design it is not even possible to sit down and say I want more duration here and more lift there and come away with anything worthwhile.

Diesels are as particular with opening and closing events as much as gassers are. Crossover and rpm range really play a part in making it all work. Exhaust housing sizes, fueling levels, and on and on.

Part of the reason I am biased toward the DD camshaft is the dyno work that was involved in the development. DD would have a cam ground, unzip the engine, install the cam, zip it back up and dyno test. Then test check results with different components and try again. This was repeated 21 times with the 24 valve engines Literally months of work.

Of all the vendors who sell cams I have not heard any bad results from anyone yet

Don~

 

Thanks Don Im gunna give them a shot & see if it works out.Kurt.

 

From what everyone has to say about them...they are good folks. Im more than certain it will work out.

Don~

 

[quote author=Don M link=board=7;threadid=18946;start=15#msg178667 date=1062253681]
Piers Cam is a stock 24 valve that is reground. It retains the press on gear that Cummins uses for its lower HP engines ( 300HP and down ) The marine engines up to 300HP use the press on gear. Once the power is stepped up to 315HP on the marines, the bolt on gear style gear is used. Much of this was to deal with harmonics and vibrations that cause the cam gears to walk off the end of the cam with higher rpm and the load of the P pump at full rack. The stock 24 valve engines many of you guys have was governed to 2700-2800 rpm via software in the VP-44. The VP-44 does not have the same parasitic drag the P pump does. This helps to keep things together. Fueling boxes, big injectors, twins, etc all help the 24 valve engine to rev higher. I see them go 3800 rpm now easily.

Diesel Dynamics uses a new marine cam with the bolt on gear. This cam is made from high nickle content chilled ductile iron and has been shot-peened behind the number 1 bearing journal ( where stress cracks happen and cause breakage ) The bolt that holds the gear on the cam goes to the number 2 bearing journal. This helps to tie everything together in the known trouble spots.

Last year when this was a hot topic I was told that the stock cams do not break and there was nothing to worry about by some. I had seen them break behind number one and had a few friends spin the gear off at higher rpm so I knew it was just a matter of time. At May Madness this year, Mark Kendrick broke a camshaft while hot-rodding around Vegas. Although I did not ask where the stick broke....Im pretty sure it was behind bearing number 1. When he told me the rocker arms behind number 1 were not moving. I knew the cam had broken.

His truck was a P pumped version though. The load the P puts on things really seems to be a partial cause of the broken cams. He rpms his truck high as well.

IMO most do not need an aftermarket cam until they get to 500HP plus. The stock 24 valve grind is not that bad to this level. Once we go higher in power and fuel I feel they are helpful.

Both cams seem to aid in power, EGT reduction, and help spool up. Price wise the Piers cam is less bucks. The DD cam has more cost in pats alone than Piers charges for the entire cam Cummins can have the thumbs down for that one. They dont give away marine parts.

Nathan Wright uses the Piers cam and has had good results with it. I have some dyno and comparitive evidence that suggests it is helping. The breakage issue with stock cams has been discussed and is a concern at his current HP level.


Anything you can do to lighten the valve train is a good thing... i.e. the titanium retainers, etc. One must be careful when using titanium components for everyday use. Most will agree that they are not a long term component. In my case I would use them. ( not driving many miles per year, etc. ) Long haul guys that tow and drive a bunch should stay with the stock retainers and collets or use another material. All out performance is tops with titanium, just not long term. Although this informantion is a few years old and alloys are changing like I change socks...it may now be possible.

Don~








Don,
Some of your information is different then mine. Before Piers had cams for sale I tried to buy a DD cam. Price was $3000 at their shop only. That meant a 3000mile round trip with motel and time off work to let someone else unzip my engine and slip in their cam. I like to do my own work.......

I checked out the marine version with Cummins, don't remember the exact price but not a lot more then the standard cams at wholesale price. The marine cam and gears are beefier due to the rated load on commercial marine engines. The commercial marine 5.9's are made to run at 200rpm less then max for hours on end while at high loads. Much different loading then our trucks. The VP 44 truck are not governed at 2700 or 2800rpm. Stock they turn 3250 and the '03's with the common rail do ~3500 rpm. The VP's do start to defuel around 2700. While there are exceptions, the bulk of the commercial marine engines are designed for lower rpms and higher loads then the Dodge ISB's.

You mentioned that Piers grinds stock cams, which was true but DD just regrinds marines cams too. I found a good source of OEM Cummins cams a while back and contacted Piers as I knew he was low on cores. He told me that he had just ordered a large number of new "blank" cams and was having them ground to spec's. You'd have to ask him the metal content but they are new blanks.

I very much agree that P7100 injection pumps load the cam and gear train much more then the VP 44. If anyone should have trouble it's me. I'm at least asking for it with a 13mm barrel's Ppump on a OEM reground cam. I've pushed mine (well) past 4000rpm and can tell you that the rest of the valve train is far weaker then the cam gear. Crappy valve guides all the way to crossovers. I wouldn't be a bit concerned about camshaft strength at VP 44 speeds. What kind of horsepower do your 3800rpm VP equipped engines make at say 3700 or 3800 rpms? Just curious. I do have an 5.9 12V engine stored in my hanger with the camshaft in three pieces...........the rod cap failed due to a very seized piston, knocked a hole in both sides of the block and trashed the cam. To much heat from overfueling. How many of you folks are breaking camshafts? Larry





[/quote]

 

Does anyone have specs on these cams? Stock or aftermarket?

 

Hey Larry,

The DD cam was never 3000. It was 2500 installed. Now it is 1500 over the counter. This allows you to install yourself now if wanted

This policy was to delay copy cats from snatching the profiles before they could get any sold. In todays diesel market this is becoming a problem. I dont blame them.

Looking at the "buzz words" in camshaft threads now sounds just like Joes original thread back on the TDR after they announced the newest cam. " Faster turbo spool up" "lower EGTs", etc.

Not all Marine cams use the bolt on gear. Perhaps you picked one of the standard versions? The DD version marine cam and gear alone, even at dealer or wholesale cost exceeds the cost of Piers cam complete with tappets.

Piers uses reground tappets. DD uses new tappets.

Generally there is never an end to concern for breakage. I dont always want or like to over-engineer something that is not causing a problem, but I have heard and seen cam gears walk off the end of the cam. I saw Mark Kendricks cam broken and have spoken to several Cummins B series engineers who had the test data back when the cam updates were released. They went to the updated cam and gear material to deal with breaking cams in industrial engines.

Here is some text from the Cummins File group 00, for the 4b, 6b, and ISB engines. It is directly copied from the CD from March of 98

"Check the location of the gear relative to the cam. Helical gears tend to "walk" out on the cam nose as a result of axial forces induced by the gears during overspeed. Check for signs of excessive heat build up at the front of the cam support and rear cam bushing"

The gears do walk off. According to Cummins it happens alot.

I knew the engine speed could go higher than 2800rpm on the ISB. I meant the fuel delivery and hence the pump loading on the cam gear was lowered after 2800 rpm from the stock ECM calibrations. With the fueling boxes and the increased full load delivery curve they bring ( comp versions, drag versions, whatever) adds strain to the cam gear. Higher rpm and higher load = higher stress. The bolt on gear helps to stop walk off and the tougher material helps to stop breakage.

BTW, the newer Cummins Common rail engines you brought up that turn the 3500 rpm...use straight cut gears. No cam walk off from a straight cut gear and the common rail pump has a very low parasitic drag when compared to a P or even the VP pumps. They did this because they knew the reliability is low with helical gears at high rpm and camshafts that dont use the bolt on system. Harmonics are lowered as well. This translates to a cam that is less likely to fail.

Stock 24 valve regrinds that cut the base circle down on the lobe, use a helical gear, and have a big P pump driven from them are in the catagory of real concern. Its not over-engineering IMO to use the best available to you for this application.

HP at 3800 rpm is still over 550. Too fast for the fuel expansion to keep up with the piston travel, but you gotta do something to deal with too much track and not enough gear. LOL! Perhaps a second overdrive.




Big Blue,

The specs are lame. Very lame. Think of the smallest cam possible and you have a 12 valver Less than 160 degrees of duration

Don~

 

In the end everyone is gonna make up their mind what they want to run for a cam. Be it stock, DD, EE, Piers, whomever.

Not one complaint is out there from any of the vendors cams. No one has broken a Piers regrind, a DD regrind, or an EE.
Well.... except UPS, they can break anything

Will a DD marine cam break? Yep. They all can. Even a Billet.

Such is life.


Now I have a real problem on my hands. Seems my 7 year old daughter went to a birthday party at a friends today and they decided to play barber shop. She has had nearly all her hair wacked off and Mom is freaking out. Broken cams are childs play compared to the old wet hen I have raving over here now.

Don~

 

What about lift?

 

[quote author=Don M link=board=7;threadid=18946;start=15#msg179317 date=1062445985]
Now I have a real problem on my hands. Seems my 7 year old daughter went to a birthday party at a friends today and they decided to play barber shop. She has had nearly all her hair wacked off and Mom is freaking out. Broken cams are childs play compared to the old wet hen I have raving over here now.

Don
[/quote]