PREDATOR-Z

T1 221/221, .558/.558 112+4 (at least the ones I remember seing)

Patrick G

iTrader: (14)

The keys in making the valvetrain live for long endurance events are proper geometry and proper valve spring selection. If you look at NASCAR Cup motors (unrestricted), you'd be surprised how little duration they run in relation to their lift. The rate of lift is un-godly and might go against the popular thinking on this board, but you also have to remember that their geometry is spot-on, the reciprocating weight is very low and the valve springs seem like they were wound by the creator himself.

OK, back to reality. In my opinion, you should take the NASCAR approach and run a cam that has lots of lift and not a lot of duration. The Comp LSK lobes were developed by Lingenfelter a few years ago and were designed to address the fact that typical fast-rate LS1 cams were launching the lifters off the lobe. Basically, they were too "square". By extending the lifter's intended arc (by adding additional lobe lift), the lifter tended to stay glued to the cam lobe and valvetrain stability ensued.

For a road race motor designed for maximum power in the 4000-6000 range, I would limit my intake valve closing point to 40 degrees ABDC (at .050") and narrow the LSA some to keep the mid-range robust. This would give you good torque down to the 3000 range and would still pull strongly to 6500.

Comp LSK 223/223 .636/.636 110 LSA, 108 ICL (+2)

Richard@WCCH

iTrader: (3)

Maybe I missed it, but what rocker arms are you using? The stock rockers can only take so much valve motion. I believe Katech is on the right setup. Plenty of torque to pull off the corner and still have some power left for the end of the straight.

Keep us posted on your progress.

Good luck,

Richard

Bombguy99z28

I have a 220/220 .581/.581 110 lsa 106 icl. I might try that katech cam next, depending on which of my heads I use. I have some AFR 205s unmilled and some 5.3l 11.8:1 scr heads, trying to decide which to play with and what cam to play with next.

jrp

iTrader: (16)

im running the jesel SS shaftmounts.

Z06er

Rich@WCCH

In all fairness, why don't you qualify your cam suggestion, as stockers, upgraded stockers, SLP 1.85's, Yella Terra's, Harland Sharps, Comp Cams, as well as the host of shaft mounted rockers from Patriot, T&D, Crane, Comp, Jessel and others expand the horizon of valvetrain and cam combos into infinity.

As a guide, lets go with something anybody on this forum can afford without EBAYing the wife's car and having her take the bus.

Z06er

Thanks Patrick G for your post. As always most helpful.

As an aside, how about a milder grind for those of us who don't have dedicated race cars? Along the lines of your recommendation, what would work as a street and track combo?

Inquiring minds need to know.

Patrick G

iTrader: (14)

Actually, what I recommended was for a street car. A race car would have me recommending a MUCH faster solid roller grind. I run LSK lobes on my daily driver. 4 school zones every morning! My car sees a lot more 900-1500 rpm driving than it does 6000+.

A 223/223 LSK lobed cam would be incredibly streetable and when you grind it on a 110 LSA and put the intake valve closing point where it needs to be, you turn your motor into a torque monster. Just the trick for those low speed sweepers and tight turns.

Richard@WCCH

iTrader: (3)

It seems to me that the cam Katech was recommending would work well with stock or aftermarket rocker arms. The stock LS1 ports peak their flow at around .500"-.550" lift. Cams with lift values much over .550" show diminishing returns on horsepower production. You can however choose a cam profile that will build greater midrange torque by placing proper lobes to suit your driving needs. Cam lobes similar to the ZO6 with advanced centerlines should make a broad torque band while allowing the use of stock rockers. This keeps the cost down and the durability up.
Let me know if this makes any sense.

Richard

SUTTERERMAN85

iTrader: (42)

i like the sound of what Patrick is saying sounds quite interesting to me.

Patrick G

iTrader: (14)

This would be fine for stock heads, but this thread is about running ported LS6 heads or AFR 205s. Those will flow very well in the .600+ lift range, thus the recommendation for cams with more lift. FWIW, the KATECH torquer cam is a tiny LS6 cam (204/218 112LSA) with a narrower LSA and advanced intake centerline. While good for low speed power production, it's intake valve closing point is way too early for superior area under the curve. It's going to run out of breath too fast once the tach goes above 5500 rpm.

Z06er

Patrick

Now that's a cam grind! I checked the Comp Cams catalog and couldn't find any info on the LSK lobe profile. Did I miss something?

Patrick G

iTrader: (14)

Comp may not list them in their Mater Catalog, but I assure you, they do exist. Do a title search on this board and type in LSK. You'll find all the specs there.

Geoff

iTrader: (3)

I basically agree with everything Patrick has stated. One thing to keep in mind, for the purpose of this discussion, is that most of lobes listed here for hydraulic roller cams would hardly be classified as hard on parts with proper valvetrain setup.

Think about it like this: Most of the gains in recent cam design have been from making 'agressive' lobe profiles that won't kill parts in the process. The caveat to all of this obviously is that as the lobes get more agressive correct valvetrain setup such as geometry and good springs (PROPERLY INSTALLED!). With proper setup I wouldn't hesitate in the least to run an XE-R or LSK lobed cam in a roadrace setup. If we are talking solid roller profiles, then that becomes another discussion entirely.

IMHO the biggest factor on a roadrace vs. a dragrace cam is how wide your powerband is. In a dragrace setup that is done correctly you can use a cam that is fairly peaky. With a proper transmission and gearing you can keep the engine operating in a narrow power range on the dragstrip. Typically in a roadrace the driver doesn't have the luxury of holding the engine to say a 2000 RPM range. That setup needs a cam that will make power everywhere, just not a superhigh peak. If you want to be even more specific the type of track you are running on can also have some affect on the cam. If you are on a longer track you might want something with more topend and give up a little down low as compared to a tight track.

My 2 cents.

DAPSUPRSLO

iTrader: (14)

Guys, i asked Brian at comp about the lsk lobes and why they are not in comp's master catalog. I ran one of these lobes on my cam in which my comp r lifter came apart so I never had a chance to really guage how they worked. Brian indicated that these lobes "do not work and were not supposed to be released to the public". I think that is a very strange statment comming directly from Comp. Does anyone have anything further to add too this. Patrick G is the only one it appears that have had good success with these lobes that has posted publically. Geoff, it seems as if you've had good experiences with them too. Anyone care to share any insight on them?

Z06er

So Geoff, in your opinion, what would cam specs would you'd recommend? The Famed TR 224 seems to be a popular recommendation for the conservative bunch. Your thoughts? Also, if someone wanted something more aggressive, what would you recommend?

Geoff

iTrader: (3)

My possible explanation into that statement: When the LS1 first came out there was a certain vendor in California (who is no longer in business) who was selling cylinder heads. Someone who is still somewhat well known in the LS1 community bought a set of this vendors heads and one of their cams also. After installing them a short time later the customer broke a valvespring. Keep in mind that state of the art in valvesprings for most everyone at the time was the Comp 941. The customer had posted on LS1.com (remember them!) about the broken spring and said he had Comp 981's. I mistakenly corrected the customer that he probably had 941's thinking that only an idiot would install the 981's (which at the time were basically just better than stock) with a radical cam. At that point the vendor came on the message board and said his heads came with 981's because the 'extreme pressure' of the 941's would cost horsepower. The vendor went on to claim the 981's 'were the best choice to go along with his cams'. At this point I got out of the discussion. My opinion then as now is that the vendor didn't know ANYTHING about setting up a valvetrain. I guess time has proven me right as this guy is long gone from the LS1 world.

My point to all of this is that the LSK lobes are not 'idiot proof'. Give them to someone who doesn't know what they are doing and they will tear **** up. OTOH if they are set up correctly they are quite simply badass. If you compare what they can do to compared any other lobe @ a given .050" duration nothing else compares for a hydraulic roller. We have spun these lobes to 7200 RPM with no ill affects. We have people daily driving with these lobes. We have made outrageous power compared to some of the 'wonder cams' out there with these lobes. As far as what one salesman at Comp has said...I don't know. I know the way Comp works: They have sales people with strong opinions (as probably does any large company of the type) but their opinions probably aren't 'official' as far as Comp goes either. They are just that : Opinions. Unless you have direct facts or proof to back up your argument it really is just blind speculation.

Personally we have had sucess with these lobes and have had a bunch of customers using them (as we have directed them) with absolutely no ill affects.

Geoff

iTrader: (3)

Depends on what you are doing with the car. If you are road racing tell more about the types of tracks you are running on, vehicle weight, desired RPM range, etc.

The point I am trying to make is that while something like the TR224 is always a good safe bet we can always nail it a little closer if we have all of the particulars about your car and how you are using it.

If you need a closer reccomendation just let me know.

V8er

iTrader: (2)

Geoff,

A little more info would be great. Let's assume a C5 Z06, 3000lbs, 3.91 gears, stock bottom end, AFR 205s, headers and the other normal bolt-ons. We will also assume the correct valve springs, CR, timing chain, etc. A healthy, flat powerband from 3000-6500rpm would be nice , maybe something that will still put the car in the 425-450rwhp range?

Most of us aren't paid to win so I don't think anyone here will be changing cams from track to track.

What can you (TR) offer as a good road race cam that has a wide powerband and won't kill valve springs?

Thanks

Teutonic Speedracer

iTrader: (20)

Geoff,

I'll probably be calling today looking for the same thing. Last night I just about decided on a TR224-12. At first I was looking at cams with a max of .550" lift, but I guess .563" really isn't much. My setup is a 01 Z28, 3.42's, ~2,800 lb track only car. TEA S1 5.7, Kooks 1-3/4, HS Rockers, 918's, LS6 Valves, JWIS Chain, drilled LS2 Lifter Trays, 30# SVO's. Car is run at Watkins Glen, Summit Point, Limerock, Pocono Long. Looking for the same 3000-6000 with an occasional 6000-6500.

Looking for durability. Want to get through 15 or so 2 hour track days a year. (Yearly spring change, ~2,000 track miles).....like one 24hr Daytona with a bunch more heat cycles...

Can you do a TR224-10 or -11? What is the advance on this cam?

Thanks,
Dennis