Grant B

I would like some help in selecting a camshaft for my application.

My car is a daily driver and occasional track (ie road course) vehicle, and I am trying to select the right cam for my application. Right now my heads are stock, but I will probably go with AFRs at some point in the future. I've got to repair a oil leak on the front of the car (not sure if its the main seal or the timing cover), so I might as well throw a cam in at the same time. Naturally I want as much average power over my car's RPM range as is possible with the AFRs. I know that a cam which works well with AFRs might not work as well with the stock heads, but I don't care. I don't want to go changing cams every few months trying different stuff.

I don't care much about idle quality. Don't get me wrong, it would be NICE to have a car with a stock idle, but its not a priority.

And lowend torque... Its a 5.7L motor in a 3100lb car, IMO its got enough damn low end. Try driving a low comression, low displacement turbo car... I view low end like I view idle, its nice but not a priority. I'd rather have low-end and mid-range than an idle though, as I can always raise the idle.

My largest priority is reliability. I'm lazy, and prefer driving to wrenching. In one track weekend I can easily spend as much time at WOT as a drag racer would during hundreds of passes down the 1/4 mile. I want a cam/spring combo that offers OEM-ish reliability. Or at the very least, just something that only requires a spring change after a year of driving, which would be 15k+ street miles with ~1000 track miles. Oh, I floor it everywhere on the street as well I always keep an eye on knock and tune carefully, so I don't think bottom end reliability will be a problem.

I'm not going to rev any higher than 6400. To me its just not worth the potential trouble. With the C5 T56's gears, this means my RPM range at WOT is 4700-6400, so I want to maximize power in that range. Coming off some corners I'd imagine I will be below 4000, but as its a 5.7L I'm sure it will make enough power for street tires.

It will be catless with Z06 mufflers. I haven't selected headers yet, as I would like one with the proper runner length to match my cam. When I do heads I will try to set the proper quench clearance by using the right sized head gasket. I'd imagine this will work fine with 93 octane and 12:1 CR.

Does anyone know if the AFR heads possibly allow different valve spring sizes that could last longer?

Naturally I would also like the longest-lasting spring. Of course this also means the spring would be as weak as possible, since (all other things equal) a stiff spring does not last as long as a weaker one.

Thanks in advance for any assistance,
Grant

mrr23

iTrader: (3)

the 047 is a real nice cam. produces a large amount of torque with a nice increase in hp. for road course torque is the better option for coming out of corners and needing to accelerate. call and speak with roger about their cams and what they would say works best. http://www.vincihighperformance.com/...%20LS1%202.htm ask them about the red corvette that does road courses with their cam and rockers. i think he has their heads also. but not positive on that one.

deviate42

iTrader: (2)

id get the tr224.

Awesome cam and makes great power on stock heads

SouthFL.02.SS

I second the TR224 as a very reliable cam that will get you great power gains across the rev range (and will let you keep the low end).

Also, the Texas Speed & Performance 225 camshaft looks great.

But, if you want to venture a bit, a great cam for your application would be the:


TSP Custom 231/231 Cam: 231/231, .595"/.595", 112 LSA
Excellent Camshaft For Mid-High RPM Power. It works well on the nitrous and has an operating range of 2800-6500 RPM. 3,500+ stall & steeper gears recommended

It seems to be in your operating range, this cam makes 400rwhp cam only, and its even duration maintains a nice tq curve.
This cam + a set of Patriot Gold dual valve springs will make a great combo.

jrp

iTrader: (16)

call me crazy but i'd look into the ASA cam w/ ls6 springs.

but honestly i'd hold off on the cam until you know your head,intake , and exhaust setup and spec the cam around that rather then everything else around your cam. especially if your looking for 12.0 compression, you wont get that w/o welding up the chambers or you'll have to mill the heads ~.056 assuming your run a gasket thicknesss around .040. then you have to think in terms of DCR. with what your looking to do i dont see how you can throw in a cam now. as far as springs the standard set are PP golds; 135 seat presssure installed @ 1.800, 385 open, and max lift of .650.

SouthFL.02.SS

So true! The ASA makes a great roadracing cam.

Ed Curtis

JRP...

THE BEST ADVICE... PERIOD!!!!!

Ed

Grant B

Thanks for the advice everyone.

That cam isn't hard on valve springs? Are the ramp rates pretty gently or something?

That ASA cam looks interesting. Lots of duration considering how little lift it has. Seems like I could go higher on lift with different rockers on LS6 valvetrain since the Z06 cam has about 022" more lift? I wonder if it was designed for a class required to run the stock valvetrain. 1.8 rockers would increase lift to .555".

I just made a spreadsheet of HG thickness and head milling vs. CR, and damn you are right jrp. You'd really have to mill the crap out of AFR heads to get them to 12:1 CR.

As far as the exhaust goes, I believe you size the header length to the engine's valve events. The low pressure area of the exhaust's resonance has to arrive during the overlap period. At least this is how I understand it, but I'm coming from turbo cars so I could be wrong. I think your right on waiting until I decide everything though.

The Showroom stock cam is also designed to run on LS6 valve springs, although it requires the lighter valves and stuff too. The duration is so long, I wonder if its worth anything over the ASA cam reving to 6400.

SouthFL.02.SS

With Patriot Gold Duals, you're good for 15k miles.

mitchntx

iTrader: (14)

Don't listen to these drag racers ... you don't want to buzz the motor to 6600 dozens of times in a 20 minute session and 8 sessions over a 2 day period.

I hit road courses as well ... I did nine DE weekends last year. In the last 3 years, I've put 20K miles on my car and 75% of them have been on a road course.

I had a TR220/114 camshaft. With heads, LS6 intake and FLPs, I made 380 at the wheels and a rev limiter set to 6K ... more than enough to show M3s, 911s and an occasional C5 my tail lights.

The car was valve train trouble free the whole time running Manley springs.

Where do you run at?
Have you visited www.FRRAX.com?

Grant B

After doing some research, it appears the ASA cam was made for a spec racing class with sealed engines. A lot of people seem to think its a POS, but some seem to think its offers great real-world performance. I can't find many dynos or timeslips with it though... If it performs well, it seems to be what I'm looking for.

I wounder how badly it would idle at say, 900rpm? I've got HP Tuners, so tuning isn't a problem.

15k track miles, damn thats a LOT! Did you have any reliability problems with anything related to the driveline?

I haven't run the car on a long track yet (I just got it, it doesn't even have an oil cooler). I will probably run at Roebling Road, Sebring, Moroso, Daytona and Homestead. I have been using the C5 to tow my sprint kart to kart tracks, which it does quite well!

I had never seen FRRAX.com, thanks for the link. Doesn't look like they have much info on valvetrain stuff though.

mitchntx

iTrader: (14)

I ran an OEM LS6 clutch and a stock 3.42 gear

lsx24

iTrader: (45)

Well, you're gonna have to switch to something with gradual ramp rates. That automatically removes all TR, XER lobes. What you have left for easy lobes is the T1/B1 series, some MTI cams like the C1 (maybe) and some smaller Comp Cams absolutely. There's some useful info in this thread:
https://ls1tech.com/forums/showthrea...hlight=reasons

Search for my post in there, where I list some general characteristics of the CC 216/220 end of page 2? With or without stock heads, this CC gives a healthy bump over stock across the powerband. It really acts like a good general all purpose bumpstick and generates some serious numbers, in a very broad powerband. When looking closely at the ls6 cam, this is just a bigger version of that, for lack of better terms. In fact, if you compare the stats to the TR "Old Man Cam" (215/220 .600/.523 115 LSA), it's an interesting comparison and the numbers generated are telling. I mean, the description of the OLC states: "This is the perfect cam for someone looking for a stock range power band...Significant horsepower gains throughout the RPM range."

Therefore, it makes sense that a 216/220 .525 .532 114, which is specced just slightly more aggressivly (duration & overlap wise), can generate those kind of numbers and more. However, where it differs is in lift and ramp rates. The OMC has steep rates and very high lift, so it's not going to fall in the same generic catagory as "low maintenance". From what I understand speaking with tuners shops and Comp themselves is that their 216/220 is not a freak but designed as a strong street performer with or without ported heads, and will not have any holes in it's powerband. It might idle a bit rough, but nothing I would consider "lope". I have a 20 MB video clip of a member with that cam, a nice recording actually where you can hear how good this cam idles, and it not only sounds sweet but in reality you can hear it just that little bit when standing outside the car. I can host the clip if anyone is interested...

So, hopefully this may add another viable option to your quest. I know that in RR you are not at the top of the powerband all the time, so the more variance you can factor in, the closer you'll be able to realistically reach your goals within your search. You could argue why would you look at so many cams when you can just pop in a TR and be done with it. You know, if it were that easy Vendors would not be ramping up their ramp rates because of increased performance, when they know very well it decreases valvetrain life. I'm sure they'll continue to do that while this type of cam sells so well. With the "right" powerband you should be good to go on the street strip or track with any of these cams, and with the healthy midrange and respectible top end of something greater than the ls6 cam, it's really a helping bonus that you can run with a set of springs for a lifespan rivaling OEM. Hope this helps.

marc_w

First thing that came to mind was the ASA cam on LS6 springs. The combo should last for quite some time.

My train of thought leads me to believe anything over .550 lift is not easy on springs if you see a lot of high rpm use.

I like the Comp XE, or Lunati recommendation.

I'm not sure how agressive VHP lobes are. I know they mention that they're agressive in the upper lift ranges of the lobe, but the advertised durations say otherwise. I want to see if I can do a real "poor-mans cam doctor" of my VHP cam vs stock, vs the TR220 when I get it. I know just FEELING the lobes of the TR220 vs stock, the difference is immediately apparent.

Z06er

Grant B:

As a fellow road racer, I'd suggest the following: Drive the course(s) of choice using your car set up with the optimum suspension/brake/trans/clutch and gearing combo. Being a daily driver, this will be always a compromise. Tracking your car on street tires is okay for DE, but be advised, if you use R compound tires, the grip is so good, you'll need more than one suspension setting. For most daily drivers this is not practical.

Note your fastest times overall and try to note the RPM range you run your car at each track. Pay particular note to the low and high end rpm range, what gears you are in and the overall balance of the car under decreasing, increasing and full power. Alot of tracks by design will force you to short shift the car, which complicates matters. Keep this in mind if you drive one of those tracks. This will help you pick the optimum rear end gear with your transmission gearing to optimize the power band of the car.

This will take time, atleast one or more seasons. Work on your line and improve the durability of the car: cooling, lubrication, suspension settings, clutch, etc... Be advised, this is expensive as your biggest cost centers will be tires, brakes and all the ancilliaries.

Tune your car until you can't drive it faster. Find the threshold of adhesion in every turn at each track. Compare like cars driving the fastest times and find out what their set ups are...

Then based on the data you've obtained, upgrade your engine, trans and reset adjust your suspension settings accordingly. You'll blow away those spending the big bucks and powering off the track with 500hp...I've watched some guys I drive with who embrace this approach and it works..

This way, you'll work off an established baseline based on the tracks you know how to drive. Easy? Hell no. Your money be better spent in the long run, as seat time, makes up for just about everything. I can say this from personal experience as I smoke GT3's and Viper with a mildy modded Z06. Sure they may blow by me in the straights, but I catch them in the corners and its thanks for letting me pass you (the rules of the road are great...) They go too hot into the corners and its over.. off track and out of the event.

Lastly, the ASA Cam is a good one for road racing however, you will need to use the GMPP ECU specifically set up for the ASA cam. Their are better cams out there if you are not restricted to any class specific rules.

I too am looking at AFR heads, with some form of more aggressive than stock 02-04 LS6, as well as other engine upgrades to give the car more reliable torque in the 2000-5800 rpm power range. The tracks I drive on will never have me wind out the motor to 6800. I need power out of a 2nd gear gear all the way through 3rd and fourth and back to 2nd with full brakes, etc..

I am sure you can relate. Just my thoughts, as I am going through the same process...

Good luck and see you at the track.

marc_w

Z06er - that's very similar to what I get told in the motorcycle world. (I do a lot of trackdays there). I should have put two and two together.

It's not a fun recommendation (per se), but it's very true...

Z06er

Check out the T1 series. Basically stock LS6's in track prepped Z06's. Fantastic driving. For more exotic powerplants, check out the American Le Mans Series (ALMS). C5R's with restrictor plates and Kinsler Fuel Injection in action. Katech is a big powerplant supplier in this world. Good luck and safe driving.

Z06er

What mods do you have on your car? Depending on where you live (smog or no smog), your budget and skill/training level, there's quite a few things you can do to your FRC to make it faster and still reliable.

SSpeedracer

iTrader: (8)

I run a TR 220 in my camaro. No problems yet, no loss in low end. I have yet to weigh the beast, but its probably close to two tons.

A friend runs a TR 224 (425 RWHP) and beats the ever living **** out of his car, both on and off the track. He missed a track day when a lifter blew up.

equandt

iTrader: (2)

LPE GT2-3 ???

That cam sure seems to make a lot of sense to me for road racing.