Engine/Transmission (1994 - 1998) Cams, the $64,000 question

[SRay]

While everyone that makes cams don't say any specs other than Hamilton and Colt Cams (same cams between the two) what most haven't specified is the over lap between intake and exhaust. I've been told that the less over lap, the better. Anymore is poison to the diesels.



I've just pulled out an old auto book to explain the degrees, overlap, lift etc. It's for gassers but gives a basic idea on how the cams work.



I'll see if I can find diesel style cams.



Shawn

 

[Nyoest]

I didn't know the two companies were the same. Learn something everyday!
The overlap should be able to be figured by the lobe separation angle and duration but I'm not capable of that math. And therein lies my frustration.

 

[SRay]

Nyoest: Yeah, pain in the butt.

 

[Nyoest]

Just let me know how much tuition is. I'll get a student loan, again...

 

[SRay]

Nyoest: that sucks, another student loan. I don't have one yet.

 

[JohnsonJim]

THey are NOT the same company. Like Ford owning Cummins. LOL



Colt USED to grind the cams for Hamilton. There were production delays and Hamilton did not like that... and went a different direction... either to a differnent cam grinder or bought the stuff himself.

 

[JohnsonJim]

quote----



There has been a lot of confusion about our product lines in the last few months pertaining to Colt Cams. A lot of people think we sell regrinds. Let me assure you, we DO NOT. In the past I ordered cams with many different profiles until I found the one I wanted the "181/210". At that point a few years ago we either put them on regrinds or we used the same 12v blanks that a lot of big names still use. After tearing down a few engines that had some wear I started looking for a better core. At this time the OE camshafts started getting wider and wider. I decided to redesign our camshaft and use the wider lobes to decrease wear as well as make the core stronger in key areas where they usually break. At this point the idea was to have our 181/210 ground at the factory instead of Colt Cams. Although Geoff has ground the 181/210 on a few other cores for us, most likely if you bought a 181/210 in the last year and a half it was not cut by colt and it was on our newly redesigned core. If you bought a 181/210 from another vendor, it was probably cut by colt and chances are it was not our new core. It was most likely a regrind or a marine style core with much narrower lobes.



In the last few years the bulk of Colts work for us has been in grinding custom cams or one offs. Supply issues not quality is the reason for the change up. We have had substandard delivery times that have been a pain to work around and have kept people like you waiting. Since our change in suppliers, we have redesigned our entire lineup of camshafts using the latest computer designs at the same factory that was most likely the OE supplier for your truck. We have two core designs available now. They are very similar in a lot of ways, the main difference being that the lobes on version one is . 860" -. 900" and the second version is just over 1. 000". We look forward to binging many new designs in 2010 from this new partnership.



We hope that you will consider one of our new camshafts for your next cummins build. Stay tuned for an announcement on new Duramax and Powerstroke cams!



Zach Hamilton

 

[SRay]

JohnsonJim: yeah they're not the same company. Was getting late and went to bed. Haven't had a chance to correct the two companies.

Shawn