Okay a picture is worth a thousand words. Here is a picture of the difference in lift between a HC3 and the "RJ" cam at the valve. Doesn't look like much, right? Here is where having a "package" designed to work together helps.
(http://i233.photobucket.com/albums/ee157/kennybasham/100_0947.jpg)
Even though this difference looks small, there is a 30+ cfm difference in head flow at this lift on my new CNC head.
Now if you were to change to a RJ cam from a Hotcam 3 in a stock head, the difference in flow would be only 2-4 cfm with the extra lift in the stock head. If you were to replace a stock head with a HC3 with my new CNC head and RJ cam, there would be more than a 120 cfm gain @ peak lifts.
This is why I am able to knock so much duration off these cams and match or surpass the top-end power of other designs, but the reduction in seat timing dramatically improves rideability..... There is WAY more power left in the Raptor motor..... Of course I could be full of crap...... I may be the only guy that believes in this build philosophy ::) ???
I can also go the opposite way and use the same duration as everyone else, matching the low-end performace and absolutely killing them on top. Remember the theory is the average airflow gain in percent when measured at 28" is roughly equivalent to power gained. Lot's of room for deviance there, not really a hard fast rule. Tune in next time for.....AS THE WHEEL TURNS...... :clap:
I was expecting my head to hurt alot more than it is, judging by the topic of the thread. Good stuff kenny!
Any idea what the difference in flow would be w/ your CNC port and a HC3 vs the RJ?
Great info Kenny, Keep up the great work. :thumbs:
Quote from: preddy08 on March 02, 2009, 11:56:20 AM
I was expecting my head to hurt alot more than it is, judging by the topic of the thread. Good stuff kenny!
I left out
about 99.73658% of the math and physics involved 8)
Quote from: Krandall on March 02, 2009, 11:59:46 AM
Any idea what the difference in flow would be w/ your CNC port and a HC3 vs the RJ?
Great info Kenny, Keep up the great work. :thumbs:
Thanks Krandall, A tick over 30 CFM :thumbs:
Make sure you guys take notice of the chamfered bolt holes that help "broaden" the clamping load on the head gasket.
Who knew crack heads could be good @ math and physics.... :lol:
Quote from: Krandall on March 02, 2009, 12:10:25 PM
Who knew crack heads could be good @ math and physics.... :lol:
Well now you know :grin_nod:
Get a build done and put it to the dirt, lets see something more than theory.
Quote from: rutcutter on March 02, 2009, 12:16:24 PM
Get a build done and put it to the dirt, lets see something more than theory.
Hmmm.... You say that like I don't already have some out there. The prototype head is already out on a 760cc build with a smaller lift cam. I just got the heads in my hand the end of last week, so there will be 2 more motors built next week. The RJ cam is already proving it's worth, and I have some dyno comparisons.......... The theory has by all means turned into empirical evidence. As a matter of fact the 760 was built about the same time as yours, at the same place 8)
Cool, so hows it running? I am sure it's an awesome ride. What kind of numbers did the 760 put down? I am a firm believer in these CNC heads.
Kenny, can you PM me the price of the head if it is released yet??? I have not been able to find pricing yet on any of the posts! Thanks!
Quote from: rutcutter on March 02, 2009, 01:37:18 PM
Cool, so hows it running? I am sure it's an awesome rise. What kind of numbers did the 760 put down? I am a firm believer in these CNC heads.
81.6 was the number quoted on reasonable compression. A little disappointing, but the cam was not a design that would take advantage of this head. It will be interesting to see what happens when the big TB goes on. The Racers Edge head is probably the better performing head at .500" lift or less. I gave up a bit of flow under .200" lift for bigger flow up top. There is one more change I will be doing to the valve job....... The final seat cut should bring my up mid lift flow quite a bit, then I will be done.
The RJ cam is the least aggressive lobe design I would run with this head. When I say aggressive I am referring to lobe ramp speeds (or valve velocity), not duration or lift.
Kenny, what would you expect the RJ cam to do in one of Bos updated head ports vs a X-2?
how would a X-4 work with one of these heads?
Kenny, you always post good and interesting info. Thanks. :thumbs:
Quote from: NaturalRaptor on March 02, 2009, 03:36:37 PM
Kenny, you always post good and interesting info. Thanks. :thumbs:
+1 I don't always understand exactly what you are saying, but usually I can bounce it off a couple people I know and figure out whats being said.... Thanks...
is this the head we were talking about when we last spoke kenny? cuz i hope so :grin_nod:
Quote from: preddy08 on March 02, 2009, 03:24:13 PM
Kenny, what would you expect the RJ cam to do in one of Bos updated head ports vs a X-2?
The RJ should see similar top-end with real good gains down low and in the middle. Bo's head is working well.
Quote from: 1badazz_700r on March 02, 2009, 03:24:55 PM
how would a X-4 work with one of these heads?
This head should run with all the top dogs with the current crop of off the shelf cams, but it is designed to put some real daylight between us and them on the more aggressive cams. For the guys that are gonna stick strictly with the current cams, I will be selling them the good ol" Racers edge AZ head.
Quote from: kamakazi on March 02, 2009, 07:58:20 PM
is this the head we were talking about when we last spoke kenny? cuz i hope so :grin_nod:
Yeah baby!! :grin_nod:
Kenny I have a mild port head on my 843 running the X2 cam, I find it very smooth. I just had the dyno done and it made 78HP but a wopping 68 tork. How would your head do on this motor. (108 cyl with +8 strok) Stock intack and supper larg filter with your +2TB. you can PM me a price as well.
Thank You
Chris
Ordunner
PS are you going to have or be at the Oregon raptor rally May 7-10th?
Quote from: ordunner on March 04, 2009, 04:13:23 AM
Kenny I have a mild port head on my 843 running the X2 cam, I find it very smooth. I just had the dyno done and it made 78HP but a wopping 68 tork. How would your head do on this motor. (108 cyl with +8 strok) Stock intack and supper larg filter with your +2TB. you can PM me a price as well.
Thank You
Chris
Ordunner
PS are you going to have or be at the Oregon raptor rally May 7-10th?
That depends on how good your current head is. I am used to seeing 6-8 hp at peak with that cam and +2 valves, but you will see very large gains in the overrev. If you combine this head with the FCI intake, you will see as much as 12-15 hp up near 8,000 rpm(last time I saw 15 @ 8,200). I will upgrade the TB from a +2 to a +3 for free if you get this head. Of course moving to a 52 mm TB will WAY open things up on this size motor. I have a head here for already cut for another customer that I haven't heard from in a few weeks, so it could be yours......
The pricing is the same as previous heads;
$500 CNC port
$140 valves
$200 springs
$840 total assembled
I should also have the new cams in next week if you are interested. There will be no more rocker cutting with these cams. The newest cams for this design are a little more flexible than the old style cams. Lift can range anywhere from .535"-.720" depending on application. Valvetrain geometry has really been improved on this head.