Billet cam vs regrind

Big Swole said:
LOL

I can only imagin!! After doing them with the motor out, In the truck would SUCK!!!!
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I had to get very creative. I made some tools that allowed me to perform this very unreasonable task. About 5 hours and alot of frustration. I beleive I used some words that would not make my mother proud.:hehe:
 
yes, tappet, its the same as a lifter, no?

in all my years of building gas motors, i was always told you NEVER put in a new cam with old lifters because of the convex shape on the lifter. Are the cummins tappets flat on the ends?

who has reused the old tappets with a new cam? Ive seen cams that say its ok to reuse them, but colt told me I need to replace them, or send mine in to be ground, in which they put a steeper angle on them to "really get them spinning"

thanks
 
slor1de said:
My regrind made it less than 200 miles. Nothing but billet imo
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Did they at least re-parkerize the cam??? I guess I can't speak from experience though with the 5.9's. But I've had pretty good luck with Bullet Racing for cam regrinds on low rpm (under 4k) tractor engines... I just always use STP oil treatment as a pre-lube and zinc additive as well as (bare minimum) ground tappets :Cheer:
 
not to bad mouth greg hogue but i have come across a few of his cams where the hardening was bad on a lobe or 2, the lobe eas wiped out with in 20 miles, i also had one where one of the face of the lobe was very brittle and was chipping pieces off of it, these were on regring cams so its not like you know what your getting anyway,

i always recomend a new cast cam or full billet cam and not a regrind for that reason
 
It is fine to reuse the tappets in a cummins engine if the cam has no visible damage, if after inspection the tappets have no visible damage. In the cummins manual it says for re-use the tappets must pass inspection. More or less that means holding them on a flat surface and checking for a convex or dished out shape, looking for pitting, galling or scuffing. If none of these appear then you are free to re-use. This is practical and to be honest the best way to go. If you want a "performance" crown on your lifters that maximize tappet rotation, your best bet is to get your tappets refaced. This makes them mesh better with aggressive ramp rates better than stock facings. Some regrinds, if put on a cr or a 12v cam will be into the soft part of the cam. If I was running a regrind I would want a 1998-2002 24v cam to start with. Because of the LSA being about 107, most performance grinds fit with the least amount of grinding keeping the lobes the hardest and largest possible. Actually these cams will end up having within a few thousandths of the same size base circle than if the cam had started as a billet blank. They also use a wider lobe. If you do get a regrind, make sure it at least has a parkerized finish. The parkerizing's course finish, holds oil and pre-lube until the parts are mated together.

Zach Hamilton
 
Hamilton Cams said:
It is fine to reuse the tappets in a cummins engine if the cam has no visible damage, if after inspection the tappets have no visible damage. In the cummins manual it says for re-use the tappets must pass inspection. More or less that means holding them on a flat surface and checking for a convex or dished out shape, looking for pitting, galling or scuffing. If none of these appear then you are free to re-use. This is practical and to be honest the best way to go. If you want a "performance" crown on your lifters that maximize tappet rotation, your best bet is to get your tappets refaced. This makes them mesh better with aggressive ramp rates better than stock facings. Some regrinds, if put on a cr or a 12v cam will be into the soft part of the cam. If I was running a regrind I would want a 1998-2002 24v cam to start with. Because of the LSA being about 107, most performance grinds fit with the least amount of grinding keeping the lobes the hardest and largest possible. Actually these cams will end up having within a few thousandths of the same size base circle than if the cam had started as a billet blank. They also use a wider lobe. If you do get a regrind, make sure it at least has a parkerized finish. The parkerizing's course finish, holds oil and pre-lube until the parts are mated together.

Zach Hamilton
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Zach, as usual you are top notch with customer support, or in this and many other cases possible customer to be. For this reason I will be buying my cam from you.

PM on the way.
 
I don't believe hogue does anything after the grinding. I questioned the hardening myself.
 
It's not that the parkerization does much for surface hardness it is just that using Lobe separation angles(LSA's) that differ too much from the factory cams eat up a LOT of base circle and modify the nose shape considerably. This makes the lobe vary in hardness. All too often the opening ramp and nose of the cam are where the softness appears. This is why regrinds although they can be just fine in some instances are not good in others. With cam grinders using CR cams to regrind that have a lot of grinding to change the LSA from almost 98.5 to 107 or 12v cams that have VERY narrow lobes that were designed for high zinc oil and a single spring that had 78lbs of seat pressure. Now a stock cr has 78-82lbs of seat pressure and 2 springs as well as low zinc oil. Using a 12v cam that was designed for such low stress and putting 110lbs springsX2 represents 275% more valve spring pressure on the cam no wonder they fail from time to time.
Here is a list of cams widths, see how they have gotten wider as spring pressure has risen and zinc has gotten lower in oils but none of the aftermarket cams have followed suit because of the low cost of 12v cores. Our cams although competitive, have a slightly higher cost(retail) even though we have a much higher cost of production compared to the competition.


12v marine.711-.730" (the #1 choice for pref. cam regrinders.)
12v .830"-.874" on highway or aftermarket.
24v and cr .940"
6.7 1.2" (I'm in a hotel in Chicago and don't have my notes in front of me)
Hamilton 1.020"

I have had a lot of people call recently after pulling out their .940" or 1.200" wide oem cam. When they looked at the .711" wide performance cam they instantly had questions. After not having their questions answered adequately by their cam grinder they call asking me questions . It is sad people try to sell these cams of such poor cores.

Not to try to bust people's chops, but sometimes basic cam measurements and truth can do that. I welcome any factual critical analysis of our new cam core, I don't welcome any misspelled ignorant, non-factual ramblings.

Zach Hamilton
 
Zach, I just want to say thank you for posting up this information. I learned a lot, and I'm sure there are others that have as well.
 
Thank you from me also. You've confirmed what I understood from my knowledge of valvetrain mechanics that the boost pressure an seat pressure combined could cause a premature cam failure.

And i, too, have seen the other mentioned cams with failures.
 
Zach, if people with the narrow lobe regrinds want to help their longevity would wider tappets than the factory 12v's help? I ran/will run Zinc additive but if it can help to have wider tappets I may have to upgrade. I don't have my cam here at the house to measure my lobe width but I know it is a regrind...
 
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Sorry, it won't help much if any. On some grinds where extreme ramp rates are employed, they will help a little, but for your regular grinds they just offer more mass to be moved in the valvetrain. If you will look at the wider lobed cams they are designed to run with wider tappets that correlate to the wide lobe. When using our cam in a 12v I suggest 1998-2002 tappets. They are a bit wider but don't weigh that much more due to the shorter shaft on them. CR tappets weigh quite a bit more and they have in some, but not all, cases they can rub the fuel pump eccentric. On CR engines the tappets are centered slightly different and will clear the fuel pump eccentric fine.

Zach Hamilton
 
holy crap that huge difference now i kinda wish i ordered the cam with the wider lobes for my 12v.
 
No, it is a Hamilton cams vs. an "H" style. I believe this companies "S" billets are the same dimensions as the cast versions although they provide protection against breakage due to the core material, they actually have much less lobe surface area than factory and are still prone to lobe damage due to low zinc oil. They still represent 275% more stress vs. lobe surface area than the same size lobe was designed for on the 12v. The stock 12v's are actually a little wider than the "h" cam per the measurements above. Some other grinders that use regrinds use the normal 12v that is a little bit wider than the one in the comparison pics. The wide cam in the picture is a Hamilton Cam and is actually quite a bit wider than the factory Common Rail cam. Once again these are just measurements. I am not going to mention names, to try to keep this thread civil. Before you buy a cam for you common rail, or 24v, you might ask your grinder if the cam was ground on a 12v or a 12v marine core or better yet just ask them the lobe width at the cams nose where there is the greatest stress. I just gave you the factory cams widths so now you can ask educated questions and get straight comparisons.

Zach Hamilton
 
I recieved my regrind from Fletcher yesterday, and thanks to Zach, I immediately went measuring lobes. The lobe width at the nose varies from 1.22" to 1.29" , I assume I got a 6.7 core. The only thing written on the core is Brazil, and some numbers.I also like how the lobe is cast as part of the adjacent cam bearing journal, this has to make a stronger core. I went with Fletcher because several people I spoke with very highly recommended him and he spent almost an hour on the phone with me the first time I called! Now that I have seen some of his other accomplishments, I am even more impressed with the knowledge and experience his suggestions are based on. Absolutely no offense to anyone else selling cams of any design, I am thrilled that Zach is bringing to light some of the differences in cams other than "mine's better, you should buy it" . The market for diesel cams is tiny compared to the gasser world, and we're all going on a suggestion from the grinder as to what to run based on our combination and needs. I'm going to break in the cam with stock springs and some good oil, then we'll put some spring pressure on it incase the revs get a little higher than expected. I can't wait to get it installed, we'll see!
P.S. the cam is not re-parkerized if anyone is interested. Killer B going in a 06 CR with a CP3.
 
I am glad you are happy with your cam. As long as you know what you are getting, I am glad for you, I just don't like people blindly getting what comes down the line.
We have a slightly higher cost in our cams because they are all new cast billets, they are all parkerized and they all have wide lobes that came at a tooling cost. Factor in the that there is no core charge or return shipping and the cost start to look similar.

I am glad there is competition, it drives each company to do it's best, and the consumer reaps the benefits. In the past there was no competition and the consumer got , well, not the best and paid dearly for it. Some people got rich with sub par products, you know who you are.

Zach
 
slor1de said:
My regrind made it less than 200 miles. Nothing but billet imo
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slor1de said:
Greg hogue says i had an oiling problem? Yet there's no signs off it imo. I've showed this cam to the guys that build our sprint motors(Don Ott and Rider) and they laughed when i said i was told i had an oiling problem. The lobes wore off. Maybe i got a bad one, i'll never have nothing but billet when it goes back together and Never another Max Spool product. If anyone wants to see it. I'd be more that willing to ship it to you to look at.
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slor1de said:
I don't believe hogue does anything after the grinding. I questioned the hardening myself.
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The last thing I want to do is jump into a camshaft pissing contest.
I can tell you that when I spoke to Greg and Bullet both on this cam, I was told that we were dealing with an issue with retainers contacting guides. Not oiling. I don't care what your cam is made out of it won't stand up to hammering.
That is all.
 
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