Jimbo1367

I really like Darths cam specs. I’d prolly limit lift though. .620. CHE reunions

DavidBoren

Comp has a shelf cam that should work well for you... 231/239 617/624 113+4... grind number: 281LR HR-13. It is a church port cam, but should work fine. That cam is a 10 second cam according to Tusky's cookbook. In multiple configurations ranging from SBE LS1's to 395ci strokers.

SLOW SEDAN

iTrader: (13)

I would hope any aftermarket 23x 600+ lift cam is a 10 sec cam. OEM L76 cam has gone 11's, OEM LS3 cam has gone 11's, GM's ASA cam has gone 9's. In the right combo a 22x cam is an 8 second cam, so depends on a lot more than the cam alone.

Tuskyz28

I can assure you that its a Shelf cam out there by someone that will work great. It comes down to SELECTING the right one for your surrounding components. I've seen smaller cams go faster than bigger cams and bigger cams go faster than smaller cams.

Open your mind and options about on where the come from. Its plenty of cam vendors that people never mention on here.

Jimbo1367

this is so true.

Summitracing

The 8720 would be a great fit for your combo. You'll see gains down low and it will hold power well at peak. We have it available in combos with springs or with springs and an installation kit. You can view all of the available combos for the 8720 here.

ddnspider

iTrader: (26)

As far as cam comparisons, one should ask themselves if they should be hanging onto the posts and spec's of someone who doesn't actually build anything and lives in a world of theory. This isn't directed at anyone specifically, I just find it tough for someone to argue theory about hp/c.i. and power/et when others have gone out and built something and have real world experience that disproves the "theory". It's been discussed ad nauseum that Holdener skews the tests to give the results that he wants. I am NOT saying his videos are not interesting and informative or that he fudges data, but there have been multiple tests where the test itself was biased and the outcome was already predetermined based on how the test was ran. That said, my next cam will likely be from Summit Racing.

indyjps

Interested in more info on the close duration split (228/230) VS the normal 9 to 12 degree most LS cams are based on. Whats the advantage to this?

Im building similar engine 6.0, LY6, gen 4 heads, vvt delete, flat top piston. T56 magnum, 4.11 gear. Been looking at the following 3 cams, prefer to stay around .600 lift for spring choice and valvetrain life.
SUM 8708 231/242 113+3, .600/.600
SUM 8707 226/238 113+3, .600/.600
SUM 8720 218/227 112+2, .600/.600

Darth_V8r

iTrader: (4)

In general -- Your close splits, single pattern, and even reverse splits vs your wider traditional splits will result as follows:

.......................Narrow Split....................................Wider Split
Intake ............no change........................................no change
exhaust..........later open.........................................earli er open
benefit...........increased midrange torque...............carries power better past peak
trade off.........sacrifice rpm potential......................sacrifice lower end torque

That's a huge generality, but to try to give you an idea. Basically, by holding the exhaust valve closed longer, you help extract work from the combustion cycle, which shows as increased torque. However, this restricts the ability of the motor to exhale as RPM increases and time available for exhaust gas expulsion drops, resulting in a faster fall-off in power after you reach peak power. You can help this by increasing the amount of overlap, but this almost always results in increased exhaust duration anyway, thereby negating the point.

Hope that helps a little.

Summitracing

There are a few of us that preach this, but Summit goes off of the four individual valve events to compare and determine behavior. There are some generalities about advances and LSA etc., but unfortunately things can go sideways really quick when picking cams that are even 5 or six degrees different.

What we'd ask you to do is plug two or three cams into our Summit Cam timing Calculator to "break out" the individual events. Then you can truly compare the behaviors of each. We did a video here that explains what each of the events do in order of importance. Here's an article that's pretty concise.

We think you are really going to be surprised at what you see and probably have 25 more questions following, but then we can truly get down to exactly the cam you need. We will reply as quickly as possible, but you can always PM us too.

indyjps

Darth_V8, appreciate the explanation. Ive been reading thru posts on duration split recommendations between Cathedral and Gen4 heads.
Ran various staight and split duration cams during SBC days, want to get the same level of understanding with LS.

Darth_V8r

iTrader: (4)

No problem. Gonna sound funny, but I don't look at the head architecture all that much when I'm working over cam specs. I look at displacement, rpm target, and compression.

Basically, bigger CID means later IVC for the same rpm. Later IVC means more room to increase compression (within reason for the fuel, of course). Higher compression means the work is extracted faster, so less compromises when opening the EV earlier.

What this means in practicality is your bigger motors have bigger cams and tolerate more compression, resulting in higher splits. Splits and compression tend to also increase with RPM. Don't worry so much about the square vs cathedral camming arguments. They're fun to get into, but int he end, have less of an influence than the other factors.

TURBOPOWERED68

I have a stock L77 with the E-1840-P and PAC 1218 in it and LOVE IT.
The car pulls and pulls
only issue i have is the stock converter is way TOO tight..
good luck on your build and post up the results of your choices.

tom70

iTrader: (10)

Would Elgin 228/230 be a goo choice for a n/a lq4 demolition derby engine?

G Atsma

Why put ANY money into a demo derby engine?

tom70

iTrader: (10)

I can buy an engine with it already in for a good deal

grinder11

iTrader: (1)

One thing many people never mention is that the higher ratio rocker you use is that much harder on the valvesprings, all things equal. Perhaps a small contributor to all the valvetrain problems the LS7 has had? Nobody has that answer, but it was the only LS engine with 1.8:1 rockers OEM. Example:
Say you have spec'd an aggressive LS1/LS3/LS6 cam. They use 1.7 rockers. If you decide to increase lift by increasing rocker ratios, and now run 1.8s to get that lift increase, you have taken a cam with already designed in fast ramps and made it rapidly accelerate the valves open, and slam them closed. I'm more in favor of the cam having been designed for a certain ratio rocker, and sticking with that ratio. Sure, on milder grinds, there's probably no harm in going with 1.8s. Just mho.......

98SSHARDTOP

stock rockers are just fine with trunion upgrade, hell...I think they're safer than aluminum aftermarket rockers.

Che70velle

iTrader: (6)

The context of what was being talked about, was using a stock rocker at greater than .625” of lift. The Oem rockers aren’t designed for that much lift, and the scrub pad begins to pull and push on the valve tip at big lifts, causing side loading on the stem and potential guide/stem wear. That’s where a roller tipped rocker has its advantages. No doubt that a steel rocker is safer than an aluminum rocker in every regard, as long as geometry can be kept in check and the springs are setup correctly.

64post

iTrader: (5)

I’m refurbishing a use LS2 from a Saab 9-7, I am using a sloppy stage 2 228-230 112 cam .585 lift, It fits without needing piston notches and RHoldener it works surprisingly well in a 6.0. This motor is rated @ 390 stock, Im thinking 450 with this cam and it’s 243 heads with a fresh 3 angle valve job.