camshaft
#1
02-03-2008 | 11:06 PM
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camshaft
Anybody have any experience whit cam for cummins 5.9?
ive found somes but not much explanation save more power less egt period
what i can gain over a cam swap and whitch brand to choose?
ive seen helix and another brand i dont remember.... not much choice and ive read swaping them is a pain in the harse whit wood dowels etc...
ive found somes but not much explanation save more power less egt period
what i can gain over a cam swap and whitch brand to choose?
ive seen helix and another brand i dont remember.... not much choice and ive read swaping them is a pain in the harse whit wood dowels etc...
#2
02-04-2008 | 12:38 AM
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Joined: Jun 2005
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RE: camshaft
Check with PDR, they make some cams that I have been looking at. Thelink below shows the crazy install process.
http://www.dieselpowermag.com/tech/d...wap/index.html
http://www.dieselpowermag.com/tech/d...wap/index.html
#3
02-04-2008 | 06:46 PM
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RE: camshaft
With a little research one will find that the major performance cam makers such as Formula One Diesel, Scheid Diesel , PDR Diesel Performance, etc will not easily volunteer info on their cam grinds.
There are a few things to know when shopping for a cam for the CTD.
- Regrind Cams ~ This is commonly done using your stock/OEM cam as a blank. They are able to do this by regrinding the base circle of the lobe smaller than OEM. In doing so, one is able to modify the actual lobe as is needed. While I have no first-hand experience with a regrind, some users report a concerning number of cam shaft breakages using a regrind. Your cam trade-in is required in most cases in lu of about a $200 core charge.
- Ground from new blank ~ Just as the name implies, the cam is ground from a new blank and therefore can be ground to any spec.
- Billet ~ If you have to ask how much they cost, you probably can't afford it.
- With the way our CTD's are built, there's not really any room between the closed valve and the top of the piston when it's at TDC. As such, any modifications to the cam's lobes are limited to that where the valve and piston don't "Kiss". Any lobe profiles outside of that will require the piston's tops to be fly-cut. Most of the so-called Stage II cams don't require a fly-cut.
For the average consumer, a performance cam will present withmuch improved turbocharger spooling. Especially at lower RPMs. Further, one can expect as much as a 200*F drop in EGT's.
- The typical CTD in our application has the cam gear pressed on the shaft. The Cummins marine engine cam/gear interface is supplemented with a bolt through the gear and into the cam shaft.
You'll find more radical P-pumped CTDswill have the cam gear bolted on as the loadcan and does have the cam gear slip. Further, many of the after-market bolt-on set-ups claim increased shaft strength as apparently there's a number of instances where the cam shaft breaks in the fist journal.
Finally, yes, the cam install is a PITA! One typically has to remove the radiator, AC condenser coil, etc so as to be able to pull the length of the cam out the front of the engine. Obviously, the front of the engine needs to come off to access the cam. The valve covers need to come off as well as the rocker arm assemblies and push-rods. The thing with the wooden dowels is that our CTD's lifters are of the mushroom design. That means they can't be lifted up, and out of the block such as in a SB Chevy. In the cam swap procedure, one uses 1/2" wooden dowels to wedge into the lifters top so as to hold the lifter up and out of the way of the cam as it's being withdrawn from the block. It's really no big deal and is the standard procedure used in the Cummins/dodge FSM.
Hope this helps.
There are a few things to know when shopping for a cam for the CTD.
- Regrind Cams ~ This is commonly done using your stock/OEM cam as a blank. They are able to do this by regrinding the base circle of the lobe smaller than OEM. In doing so, one is able to modify the actual lobe as is needed. While I have no first-hand experience with a regrind, some users report a concerning number of cam shaft breakages using a regrind. Your cam trade-in is required in most cases in lu of about a $200 core charge.
- Ground from new blank ~ Just as the name implies, the cam is ground from a new blank and therefore can be ground to any spec.
- Billet ~ If you have to ask how much they cost, you probably can't afford it.
- With the way our CTD's are built, there's not really any room between the closed valve and the top of the piston when it's at TDC. As such, any modifications to the cam's lobes are limited to that where the valve and piston don't "Kiss". Any lobe profiles outside of that will require the piston's tops to be fly-cut. Most of the so-called Stage II cams don't require a fly-cut.
For the average consumer, a performance cam will present withmuch improved turbocharger spooling. Especially at lower RPMs. Further, one can expect as much as a 200*F drop in EGT's.
- The typical CTD in our application has the cam gear pressed on the shaft. The Cummins marine engine cam/gear interface is supplemented with a bolt through the gear and into the cam shaft.
You'll find more radical P-pumped CTDswill have the cam gear bolted on as the loadcan and does have the cam gear slip. Further, many of the after-market bolt-on set-ups claim increased shaft strength as apparently there's a number of instances where the cam shaft breaks in the fist journal.
Finally, yes, the cam install is a PITA! One typically has to remove the radiator, AC condenser coil, etc so as to be able to pull the length of the cam out the front of the engine. Obviously, the front of the engine needs to come off to access the cam. The valve covers need to come off as well as the rocker arm assemblies and push-rods. The thing with the wooden dowels is that our CTD's lifters are of the mushroom design. That means they can't be lifted up, and out of the block such as in a SB Chevy. In the cam swap procedure, one uses 1/2" wooden dowels to wedge into the lifters top so as to hold the lifter up and out of the way of the cam as it's being withdrawn from the block. It's really no big deal and is the standard procedure used in the Cummins/dodge FSM.
Hope this helps.