It's simply the name of a family of lobes offered by Comp Cams. Each different group of lobes has different characteristics. In the case of the LS-specific Comp lobes, the XE is the least aggressive, followed by the XE-R, with the LSK being the most aggressive.

If I'm not mistaken, in most cases--if not every case--a more aggressive lobe will provide more power "under the curve" (or average power), even though the least aggressive lobe could provide the same peak power as the most aggressive lobe. The tradeoff for using a more aggressive lobe is the potential for accelerated valvetrain wear.

That's my understanding, though it may be erred.

Josh

 

Its the ramp rate or rate at which the valve opens. The XE lobes would be like 59, a XER would be 49, a LSK would be the same initial ramp but open faster and further in the middle of the lobe. Yes they kill springs rather fast and you should be aware that a yearly or 2 yr spring change is in order to control valves. If longevity is a concern than don't use them. No one discussing such power upgrades is suggesting that they are reliable along those lines.

Long ago, the XER lobes were slammed for the required spring pressure and springs were breaking but now XER's are daily driver lobes with current awesome spring technology and dual springs for safety. Some guys complained that 10k from a spring back then was asking a lot. Now its a new ballgame in that you can get a .650" lift and run it a long time with a crazy lobe. Using LSK lobes is a spring wear issue but not exaclty a spring breaking issue with current available springs. Expect to have to use shimmed 921's or crane 832's and if you are near limit coil bind, having to change them when they lose seat pressure.

 

There is another Comp cam lobe too..it is the XFI lobe which is between the XER and the LSK in lift...it might be an alternative for those who are not wanting to go to the higher lift of the LSK lobe..

 

XFI are expecially good lobes for smaller durations. They make a 210 duration intake lobe that's over .600" lift. That rocks!

 

XE are 53 rate variation

 

I stand corrected. The crane cam grind I had used years ago was a 59...the 'T1' if I recall. It was a 221/221 on a 112 and ran horrible.

 

That cam has the same EVO as my 228/228 114 +4 LSA Lingenfelter comp XER. But I also have a 44 IVC to which appears to help carry power a little longer. Cam peaks right at 6300 rpms, torque peak is at 4800...This cam has always worked well for me and I doubt Ill ever change it. The 114LSA and a little more exhaust bias works great for N2O as well. It also idles VERY well.

 

You get this dynoed yet?
My heads are about done so if you dont hurry up I might have to slap my heads on and throw my cam in real quick for some dyno numbers.

BTW I was looking for the XFI stuff a few weeks ago and couldn't find it.
Toss me a link if you have one real quick, other wise I will just look again.
Maybe my eyes weren't doing a good job that day.
IMO if comp has enough different XFI grinds this will become very popular very quickly.
You will have almost all the benifits of the LSK stuff w/o quite as much wear on the springs.

 

No unfortunately, I've had an embarrassing set-back. On my way to the gym early in the morning this past week, I hit a deer with my TA. It came out of nowhere! Messed up the front of my car and it's spending a little time in the body shop.

The closest chassis dyno is 2 hours away from me so it just hasn't been convenient with all my work lately. The vast logging I've done indicates strong boost in torque from 2000-4500 and comparable power at higher rpm. Just the ticket for road racing and tight autocross courses.

 

Sorry to hear about your mishap..in Georgia they are everywhere..I had to go down in a ditch to keep from hiting two of them back last September. The policeman that did the accident repot said that he has at least one a week deer vehicle incident..I hit a deer in a Vette back in 68 and the car was in the body shop for a while...they had to put a whole front end on it..on top of that the deer came in through the windshield..if I had not ducked he would have possibly killed me too..we are all dying to see the dyno results on your cam...Glad to hear that your are all right..they can always fix the car..keep us posted..

 

OUCH.
I have seen like 1 deer in fla my whole life.
I do however remember taking a road trip with my X to her parents house in PA.
We were like 3-4 miles for her house and it was late at night.
I was driving.
Out of nowhere I saw a deer, and being from Florida I.........................

Said look honey a deer, and just kept driving.
3 seconds later SHE (my x old lady) hit me and said you stupid *** your lucky he didn't run out infront of us. You should have slowed down....
OOPS.
Sorry that happened.
Hope all goes well in geting her fixed back up.

Hey you have a link to the XFI stuff?

Also I changed my cam a little bit for my own wants.
Its in the sig.

 

Hi Patrick

Glad to hear you are ok, my dad had a similar misadventure some years ago, it went pretty bad and the car was destroy plus bad insurance....

No physical damage is coming first, on this point it's going well, your jewel is going to be repaired, and it seems that your # are going to be strong.

All the best
Christian

 

sux but at least you get new paint. Make the best of it. Soon you wont care or remember.

 

Sorry about your car man, glad your ok!

 

Here come all the deer stories.

 

When choosing a cam for a FI setup wouldn't too much DCR prevent running more timing? I can see it making more power if running race gas, but what DCR would be ideal for a pump gas setup.

 

Ideal DCR for 93 octane is between 8.5-8.8:1. With 91 octane, 8.5:1 DCR is achievable and a good number to shoot for. Turbo or supercharger, you'd want to run lower DCR, but nitrous you'd want it very high.

 

I wrestled a deer once......

 

Okay......

So if a guy wanted this same cam, what's it gonna cost to have TR grind another one?

 

about 420 shipped to you with them verifing that its correct on there cam doctor