Mr. Sir

https://ls1tech.com/forums/generatio...am-change.html

I've seen this thread by Pat G discussed a few times before, and I know others have asked this question, but what would be a gentle lobed version of this cam? I'm thinking EPS 226/230 110+0. I'm also thinking the .006 and .200 values may have a significant effect on the dynamic compression/valve curtain area, which is where my main problem figuring this out myself comes from. If there are better/ more gentle/ quieter lobes for a cam with duration between 220 and 230, I'd like to know (in addition to opinions on cam specs).

Any opinions?

Fbodyjunkie06

iTrader: (10)

Need a little more exhaust split. Like 226/234 or 224/236 110 lobe.

But that's just me though!

Mr. Sir

I won't be keeping the stock exhaust (most likely), and will be getting at least 243's, so the exhaust won't need to be split so greatly.

Alrighty, if nobody can answer the question as a whole, let's break it down:

@ .006:
LSK ?
EPS ?

@ .050:
LSK 224/228
EPS 226/230

@ .200
LSK ?
EPS ?

Max lift
LSK = .637/.639
EPS = .598/.600

LSA:
LSK = 110
EPS = ? (probably 110)

And probably little to no advance on the EPS cam, since there's no advance on the LSK cam.

Even if the EPS cam is down on power by 10rwhp everywhere, it's the general powerband I'm looking for, not peak numbers. If anyone has the missing information, I could use it.

99Bluz28

iTrader: (35)

Have you considered a 223(.610" lsl)/226(.605" lxl), or maybe a 224(.609" XFI)/226(.605" lxl) ? I'd also try and go with minimal duration split for better torque. If you decide to go with the larger duration EPS cam, then you'll want to run some advance to shift the power band a little lower. For good power, and minimal valve-train wear it would be hard to beat the EPS lobes, the lsk lobes are really aggressive, probably not what you want at all.

Mr. Sir

Yeah, I'm just trying to compare the curves. Even if the eps is down because of it's lower lift and ramp rate, if it comes within 8rwhp (theoretically), I'd be satisfied. I did think about 2 degrees of advance, considering the cam is 2 degrees larger.

Is the lsl lobe about the same as the eps? I considered eps/lxl, and even lsl/lxl, but don't know much about the lsl/lxl combo (except the lxl is as soft or softer than the eps lobe, which is why it's used to quiet the exhaust). LSK lobes were never in the picture; making the same power as them was.

A.R. Shale Targa

iTrader: (2)

EPS lobes are fairly aggressive yet designed to be beehive compatible and
have good valvetrain longevity. Geoff also plots the intake closing point at
the sweet spot to maximize cylinder pressure. He doesn't just move it
around for idle or power band generalizations.

Mr. Sir

Then perhaps he can help? And yes, I was concerned with DCR as well, but figured it'd be within .1 of the LSK cam, given the near identical specs.

RonSSNova

iTrader: (3)

I have a 223/227 .639/.640 114+2 cam with LSK lobes. I was about to install it. Got nervous about the LSK lobes and contacted Pat.
I now have ordered this:
226/230 .598”/.609” 114LSA +1 EPS/LSL
Combo will be stock short, AFR 205 @ 61cc, FAST 102 + 90mm, Headers.
C5 Vette with 3600 and 3.42.
It will be a summer DD and see plenty of drag strip time.
Won't run till spring, but I am excited.

Ron

hammertime

iTrader: (1)

Patrick has commented before that EPS 226/230 cams are the rough equivalent of the fairly common XE-R 228/232 cams. To that end, you may be just a tad better with a 222/226.

Pat also prefers the 4 degree split on exhaust for AFR heads so that the curve pulls smoothly past the peak without nosing over too quickly. How much split you use will depend on the Int/Exh ratio of the heads you will be running, exhaust in question, and how long you can keep the exhaust valve closed to extend the power stroke, while still effectively evacuating the chambers when the exhaust valve closes again.

Mr. Sir

kay.

LSL or LXL? referring to Ron.

I'll look for the build thread some time, and see if the power curves are similar.

Heads will be cathedral port, no worse than stock 243's, and probably no better than ported 243's. Since this is more of a theoretical thread, assume the same intake/exhaust setup as Pats original thread. It seems basically every free flowing cathedral setup likes around 4 degrees more exhaust than intake. If this is an incorrect assumption, then is there a more accurate split?

hammertime

iTrader: (1)

The exhaust ports as cast on 243 heads do not typically flow 80% of the intake like an AFR head. In that case, a slightly larger split of 6 or even 8 degrees may benefit. If you have an excellent 1 3/4" header, or a 1 7/8" header, the four degree split is probably fine.

Ported heads also shore up that weaker Int/Exh ratio.

Mr. Sir

Mkay.
so 222/226, 226/230, or maybe 222/230.

Still unsure on LSA or ICL.

Alright, input is still welcome, but I think I've found my answer.
https://ls1tech.com/forums/dynamomet...450-434-a.html
450/434. Maybe it's a mistake, but even if it makes 10rwhp less, it's still impressive. Even with less ramp and lift, it comes quite close to the 459/410 that Pats 224/228 LSK made (with AFR 205's). It seems like stock 243's+EPS cams make huge numbers.