bobbss

Would a lsk lobe with less then the normal lift for lsk lobes be of any help?A 224 xer lobe has .581 lift,would a 224 lsk lobe with .600-.610 be worth doing?What would be the normal lift for a 224 lsk lobe?If you have a lsk lobe with the same lift as xer lobe would it make more power or be much harder on the springs than the xer lobe?Thanks!

hammertime

iTrader: (1)

Have a look at the XFI lobes

bobbss

Are the xfi lobes inbetween xer and lsk?

LS1Formulation

iTrader: (13)

Pretty much, yes.

hammertime

iTrader: (1)

Here are all the comp 224 lobes I have, in ascending order by lift.
Note that the XE-R, XFI and LSK all have simular durations at the seat and .050, and that the XFI and LSK have the same durations at .050 and .200

bobbss

Thanks!Are the xfi lobes much harder on the springs than the xer lobes?

LS1Formulation

iTrader: (13)

You're talking about .028 of an inch here. It's not going to make much of a difference, really. The spring longevity will be the same for either lobe.

hammertime

iTrader: (1)

+1 on that

In reality, either one will require a dual spring as that lift.

bobbss

So the ramp rate won't be much harder on them?I have a set of RHS 210 that I bought bare when they first came out and that was the only way to get them.I had them set up with double springs good to .650 but told the guy setting them up that I wouldn't be going but maybe a hair past .600 because I didn't want to push things to their limit.I don't mind having to change springs every 10,000-15,000 miles but don't want to have to worry to much about breaking springs before that.This is not a max effort engine just want to get all of the ponys I can without making it a total parts eatter or a pain to drive.Thanks for all the help!

Ragtop 99

iTrader: (7)

I use an XFI on the intake side, but I went with an XER on the exhaust.

Note that the lobes starting at 3033 are exhaust lobes and not as aggressive.

bobbss

I called Comp and they said the down side XFI lobes would be alittle harder on springs and make alittle more noise.On the up side they would probably make about 6 hp across the whole rpm band.Does that sound about right?

Asmodeus

Yes.. and LSK are even a bit harder on springs, but will make a bit more power than the XFI..

..at each given duration, the XFI will have the valve open farther for longer than the XER, and the LSK will have the valve open farther for longer than the XFI (assuming ramp rates are folling the trend showed earlier). You've seen a head flow sheet, and heads flow more air at higher lifts until they start to back up, but generally that's well over .600 lift, typically beyond .650.

2-valve engines love lift. I went with an LSK intake lobe myself. I've been told that the LSK lets the valves down easier than the XER too.. reducing chance of valve bounce.

bobbss

Did the LSK make much more noise?

DuronClocker

iTrader: (25)

Get the correct length pushrods and they won't

bobbss

Thanks for all the help!Thought I'd let yous know that I decided to play it safe and stick with a smaller cam with XER lobes.I orderd the Comp 54-444-11 (224/230 .581/.592 114+2).I fugured since no matter wich cam I go with theres a chance I might wish I had picked a different and want to change it agin.If so I would rather be putting a bigger one in for more power than putting a smaller one in because it is a pain in the *** to drive.It would probably be awhile before I could afford to do it agin and it will be eaiser to live with a small (cam) mistake than a big (cam) mistake.Thanks agin!Bob