This is Kip Fabre from Cam Motion I am new to this site I have already posted on a few threads but I will let you more about me and my company. I have been reading about cam design and application on this site and others for many years and have heard just about everything about cams for every cam guy and cam company and magazine article. Everyone has there opinion about cams how they work, what works and what does not work. Some of the best ones were it must be ground on 106 or it not going to work. One of the top engine builders in the country once told me that cams ground on 115LS don’t work! That was 20 years ago I did not tell him the guy he was trying catch had a cam ground on 115. now this was for a Pro Stock NHRA car. I will be posting on here for the next few weeks. If anyone has question please let me know. Let me say this I have been grinding cams for 49 years and design cams for 34 years. We have made cams for 6 NHRA ProStock World Champs 6 NHRA Pro Stock Motorcycle World Champs 2 Top Fuel World Champs We had 3 wins at 24 hour Daytona and many other wins from boats to tractor pulls.
Now after all that do I know everything NO can I learn something from someone that works at the tire shop YES. I learned this along time ago when I was young the old guys that thought they new everything Only knew what they had heard from someone else which was usually wrong. So her we go. The first thing I would like to take about is lobe profiles. RAMPS, RAMP SPEEDS, DURATION @ .006 What are the .200 numbers how intense are your lobes? Answer they are soft they don’t brake parts and they make more power! Why because they are more stable rev higher. I can make 2 lobe with the same dur @ .05 same lobe lift one with short dur @ .006 and another one with more @.006 what you will find out is that some of the extra duration is only preloading the valve train so you really don’t have that much extra duration. They are quieter and make parts last longer. Most of the street car are driven on the street so we want them to last 100,000 miles. We could make 5 different lobe families and call them BMF MFF CCG GFY KKR or MONSTER
And my favorite YZOOOOOM lobes. We make lobes that work. In reality ALL cams specs should be checked at the valve not at the lifter. I will show the different in profiles when you have a 1.7 verses a 1.8 later on this thread. Let me tell you more about FAST LOBES. WE just redesigned and reground 50 cams for a company that made BBC engines they were for a pump station they ran on natural gas and ran at 1800 RPMS after 500 hours the valves and valve seats were beat up so bad everything had to be changed the company that made these made FAST LOBES because it was only running 1800 RPMS 200@.05 with a .300 lobe. We put soft lobes on all of the cams we reground now they are not having trouble same duration and lift. It is just as easy for us to make hard lobes as soft lobes SO what should we do. The SECRET to the best cam is to get the timing events correct for YOUR application meaning opening and closing events which dictates Lobe Separation. More later.

 

Excellent. I am always in for more information.

 

I have a 2001 Corvette ZO6 with a 418 LS3 11.5 CR, 215 TFS heads (un-shrouded the valves to match the bore), then milled the heads .005 back to 63cc, LG G5X3 234/242/.600/.610 114 LSA installed at 114 ICL (XER lobe), LG Pro 1.75 headers, high flow cats & 3" exhaust. ported Fast 90 mm intake.

The drive-ability with 10* overlap was poor at light throttle/low RPM. Also didn't care for the valve clatter (was quiet at idle, worse at 1500 -1700 RPM)

Geoff from EPS spec'd me a Cam Motion 234/242/.600/.615 117+2 cam in January 2013. Now the car drives 10x better, no more light throttle/low RPM surge. Plus the car still has more than enough bottom end power, and pulls WAY easier to 7000 RPM.

But I'm still not happy with the valve clatter. Its a bit quieter than the LG G5X3 cam. I tried the BTR Platinum springs that have 155 lbs seat & 380 lbs open. The springs that came on the TFS heads had 165 lbs seat and 450 lbs open (can believe my Yella Terra Rockers didn't break after over 3 years with such high spring load). But the springs may of only slightly improved the clatter in the 1500-1700 RPM range. I use Joe Gibbs 10w30 Hot Rod non synthetic oil.

Do you know what lobes are used in this camshaft? Geoff said this was the first time he heard of any valve clatter with his spec'd camshafts.

Russ Kemp

 

Hi Russ
Let me know if those were EPX or EPS. If they are the EPX they were left over lobe design from the other cam company. If they are his new EPS they should not make any noise.

 

The .615" lift looks like EPX. And that's where most of the sound will come from...the exhaust valve crashing down. Tho they were supposed to be quiet.

 

I think they are EPX lobes these were lobes designed like they were using but a little softer. Like I said I do not like lobes like that. We have made cams for other company's with there lobe specs. We put there name on them not mine we do what the customer wants to a point.

 

It's a Cam Motion, the core is 3310130, and the grind# is blank on the sheet that was in the cam box. It was through Geoff at EPS. I received the cam in March of 2013. Geoff said he was switching to Cam Motion just after I ordered it in January 2013 because of quality issues with Comp Cams

The intake lobe lift is .35417, and the exh is .3622 as per the spec sheet that came with the cam.

Russ Kemp

 

That's our core and I am sure we made it I can try to look it up tomorrow and let you know what lobes were on the cam. We made EPX in the beginning. If got it in March it could be EPX. I will let you know if I can.

 

Thanks, just comparing the Cam Pro Plus report of my Cam Motion cam vs the LG G5X3 cam. Cam Motion vs G5X3 int peak lift is .35454/.351 and the exh peak lift is .36295/.358. Does this really mean that the G5X3 has a softer lobe than the Cam Motion cam?

Russ Kemp

 

! Your expertise is needed and welcomed here. Just don't get real sales pitchy. **** moderators will get there boots on!.

 

So, what range is the ramp rate/speed in for the intake lobes and the exhaust lobes, and how much does that rate/speed change from one lobe lift group to the next .005" higher lift lobe group? The duration at .006" would also be nice to have for calculation the DCR with you cam lobes.

I see on the Cam Motion website tabs for Truck, Camaro, and Corvette cams, but it only brings up the custom camshaft menu. So, are you revising the lists for shelf cam grinds ?

 

If those lobes are .362 and .354 they are the EPX lobes. If you have 2 cams one with .300 lobe lift and one with .360 lobe lift the lobe with .360 can be a much softer lobe I will get into the lobe speeds or designs later this morning.

 

This is the exact reason I got rid of my TSP 228r cam. It made good power but even with strong springs I was getting float near redline and the car sounded like a sewing machine. My new cam has Comp HUC/QXX lobes which should be much quieter. The cam has .030" more lift than my 228r had and was told it will be much more quiet.

Glad to see this thread. I've always been intrigued by lobe design. Thanks Kip.

 

Great thread and really happy to have you on here. I'm really looking forward to learning as much as I can from you.

 

I take exception to this.

Also Kip and I have PM'd. Cam Motion is a sponsor. He is well within his right to promote the company, and I have encouraged him to be more active.

 

So your saying that I removed a noisy cam & replaced it with a different noisy cam? So what cam lobe/lift camshaft could you grind for me that won't cause valve clatter? Would there be any loss in power? Do you agree that the G5X3 XER cam has softer lobes than the EPX?

Not happy, so who dropped the ball on my cam that Geoff spec'd?

Russ Kemp

 

Did you specify with Geoff that you wanted softer lobes that are easier on the valve train and quiet?

 

Awesome!!

 

Yes, I told him that I was tired of the valve clatter with my G5X3 cam, plus I was sold on the info on his web site about his quieter cam lobe design.

http://www.engpwrsys.com/tech-notes/cam-design.html

Russ Kemp

 

Well in that case, hope you guys get it figured out.