bartmanC5

iTrader: (3)

Long time reader, first post at LS1Tech.

I'm running a 2002 C5 M6 Convertible (68k miles), and am working up the nerve for my first heads/cam project this winter. My car currently is stock but for axle-back exhaust, and already has LS6 intake, LS6 28lb injectors. Fair-weather summer daily driver, 95% street use but a couple track events each year. Most driving is sub-5k RPM, so I like my torque. I like the current exhaust note (but could use some lope), and the stock power level is nearly adequate.

I have a leaking front seal and wouldn't mind a bump in power while I'm tearing it open. Trying to do a budget build, doing my own work except the tune. I don't want to go long-tubes, nor do I want a 500hp tire-eating monster.

So far I've picked up a K&N FIPK air intake, new lifters, and a low mile take-off bundle: '03 Z06 LS6 heads (sodium valves) / cam / rods / springs. Gaskets, dampner, timing chain, and oil pump TBD.

It would seem I am nearly there for a Z06 conversion if I wanted it. Except I used the search here and came up with several discussions about torquey cams using stock manifolds, one in particular. It sounds right up my alley, and nearly identical to my configuration.


(2009) 218/230 .595/.598 115LSA +4 EPS Cam 403 rwhp LS1 with stock exhaust manifolds and mild cam
https://ls1tech.com/forums/dynamomet...-mild-cam.html

Sorry for all the questions - I've been chewing on this for a while. I'm torn between the LS6 versus 218/230 cam.

Will this cam have a noticeable lope, or is it really "stealth"?

I would get new springs and rods for the higher lift. What about rockers, fuel injectors, something else?

Is the original clutch heading for trouble, or should it hold either?

Any other parts upgrades suggested while I'm in there?

Cost-wise, the EPS route adds at least $700+ to the project, but can recoup some of that by selling the Z06 cam & springs.

Both cams bump the rev limiter, but the EPS would have better area under the curve? Z06 would probably net 370 rwhp, but 400+ with the EPS is tempting.

After the cam swap, will I need to trailer the car to the tuner, or should it be drivable for 40 miles?

Does anyone have an LS1 cam vs LS6 cam dyno overlayed on the same graph? I'm curious if I should see the +30TQ from 2200rpm all the way up like the EPS, or which one "wins" at lower rpm.


Thanks for any input.

PREDATOR-Z

The EPS is -6* overlap so Stealthy, but if you fiddle with the idle and timing at low rpm you "could" make out there is a cam if you have a trained ear. Also a X pipe and cat-back will help in getting a deeper sound.
That cam should be drivable on stock tune to the tuner but stay below 4000 rpm.
The EPS will be much better than a Z06 cam.
Might need to upgrade clutch for spirited driving. I would eventually. It will be a nice ride.
BTW you could mill the 243s a bit to get 11:1 SCR or close to it. That is a few ponies right there.
I would send the heads to AI for at least a good valve job.

bartmanC5

iTrader: (3)

Thanks for the info Predator-Z.

Already have a Borla catback. It sings nicely to WOT and has a nice burble on revdown with the stock H-pipe. Is there a way to lopify this cam a bit without significantly affecting the power curve? I don't understand the side effects of altering cam specs to increase overlap.

I'm trying to figure "bang for the buck" on these 2 cam options, and supplementary upgrades. EPS cam > Z06, but is it worth adding 30+% to the project? Will I end up with significantly more power/tq, streetability, economy, etc? Will it be a more optimal fit with the other selected components to reach my goal? I know that either way I would be copying a successful combination.

For valve job, I read that the stock VJ is passable but significant gains can be found at low lift with a good one. I haven't priced it out - a couple hundred bucks with new seals? What would the net result be to the whole curve? I don't suppose anyone has a valve-job-only dyno comparison...

Until now I've been running 89 octane on the stock tune and have been pleased with the results. Milling for sure (and likely just the tune) would force me into 91, the best stuff we have up here. How much milling is needed to reach 11.1:1 with oem MLS gaskets, and what would the dynamic CR be for my combo? I would be happy with a 4% tq gain across the rpm range. Is there a reason for me to use other than oem MLS gaskets?

Any feedback on the parts list I've assembled? Anything I missed, or are there other upgrades needed with the EPS cam?

On the reliability side, I bet the Z06 cam would be easier on the valvetrain for its lower lift. What life should I expect out of Comp 918 springs in this setup?

Thanks.

PREDATOR-Z

Hi Bart,

243/799 heads and a cam will definitely yield more than 4% power increase. Just raising your compression without a cam should yield about 3 to 4% for every point raised with tuning.
You could raise your power at least 2% by properly tuning your actual setup versus the stock tune.
IMO, either do it right or don't touch it. The Z06 cam will be less expensive, but will yield less results. If properly installed (at correct height) you should expect between 20.000 to 30.000 miles out of those springs but they should be checked every 15k as maintenance.

If you worry about mileage and maintenance, just give it a good tune and leave it as is. Once you go cam and heads, maintenance increases, there is no way around it.
Or you might consider selling your car and getting a Z06 if you want more out of it. IMO to put a Z06 cam in a stock LS1 is pointless for the money spent. A few more bucks and a better cam will not even require a head swap. On a M6 you can get over 400 rwhp cam only with ease on a good cam, but keeping the exhaust manifolds limits your output.
Bottom line, there is no such thing as cheap power. You have to think about it and make a decision.

bartmanC5

iTrader: (3)

You're right. That was the 4% I was referring to. If I have to go 91 octane, why not mill to optimize the burn? How much to mill with MLS gaskets to hit 11.1:1?

Thanks. I've already bought into heads/cam and a new maintenance interval. I just wanted to know if that interval was every 5k or 15k with this cam.

I'm not at all worried about mpg changes. I was more asking about the changes for better/worse between the cams. Is it safe to assume this stealth cam will not have surge/drivability issues like bigger cams?

I appreciate your input. These answers help whittle the pros & cons down to make a clear decision. I'm leaning towards the EPS cam.

Any other components to change while there?

oddwraith

iTrader: (1)

I like the comp 212/218 114 (.522/.529), and it works and sounds great with stock manifolds imo, and is relatively easy on the springs and is a better choice than the ls6 cam imo. It's torquey and it is easy to tune. Look it up and see if it's what you are looking for, it sounds like it is. XR265hr 114.

99 Blue Bird

iTrader: (3)

thats the cam i have. and a set of AI cnc ported heads. my car is not running yet but im hoping to break the 400 rwhp range when im all done with it. just looking for a CA smogable 400 rwhp car that runs really well. either way it will run better than stock.

bartmanC5

iTrader: (3)

That's another cam noted in my reading. Pretty convincing choice, if you really will gain 25-40 tq with a low .529 lift cam and 241 heads. http://www.superchevy.com/technical/...en3/index.html (tested with headers). But it looks to run out of breath around 6000 rpm, and wouldn't take advantage of a higher rev limit. But a good bump down where I am most of the time.

Comparing the 218/230 EPS cam with the 212/218 cam, how would their power curves match up under 5000 rpm, all else being equal? Is the EPS still +10 or +20 above the 212/218 across that band, or more closely matched?

I do spend some time above 5k at track events. Does the EPS have a wider power band that doesn't drop off like the 212/218 appears to?

Aren't those heads overkill, limited by your exhaust as Predator-Z mentioned? If stock 243s with this EPS cam can get to 400, what are you expecting the CNC'd heads to do for you?

Stock CR is 10.5:1 with 243 heads. Milling to 11:1 would increase a net of 2%, or 6-7 tq across the board, correct? Would this still provide enough PTV clearance for the EPS?

Thanks for the replies guys.

oddwraith

iTrader: (1)

Well frankly, the eps cams are really doing great stuff out there. I am not sure if they would necessarily do better under 5000 rpm than the xr265hr by a significant amount. There is a reason why a lot of truck guys like the comp xr, it is because of the great curve and mid range power/tq. It does drop off after 5000 rpm, but nowhere does it dip below where the stocker would have been. If you are interested in knowing more about EPS though, I would get a hold of PATG and see what his opinion is (I believe he achieved well over 400 rwhp cam only through stock manifolds-cheater cam). I just don't see the need for as much lift as the eps you specified earlier, but the other valve events are significant factors. Let us know what he says.

Either way I'd do pushrods, springs/retainers (ls6 springs or comp 915s work), oil pump, chain, gaskets/seals (should be obvious) and all the usual if you are doing an upgraded cam. This is a small cam, I suggested it because it really sounded like it would do what you wanted.

edit: I found this link, maybe you already saw this one...
https://ls1tech.com/forums/dynamomet...-mild-cam.html

99 Blue Bird

iTrader: (3)

OP y would the heads be overkill? every bit helps. all the heads are doing is allowing more air in and out of the motor. of course if i put on longtubes and had a cam for them the motor would probably run better but you have to remember that the drivetrain that was used for the dyno results was not a F body or vette. so there is gonna be a factor there. so im trying to increase the air intake that was a slight problem with the car that is in the thread you read and am hoping that i can get to 400 whp or more. you can build 5 identical motors but it does not mean they will all run the same.

so im not necessarily chasing the 400 rwhp mark but im chasing trying to have a California SMOG legal car that runs very strong with some of the longtube guys with cams. hoping to run in the very bottom 12s or 11.9xs n/a with some 115+ trap speeds. i would love to see a 118mph trap. than if im not happy ill throw a 150 kit on.

bartmanC5

iTrader: (3)

Very helpful, thanks. Sounds like both cams have significant improvement over stock, and perhaps equivalent (?) up to 5k. The EPS would for sure outperform from 5k to 6500/6800 rev limit with 243 heads?

Would the 212/218 low-lift cam benefit from a rev limit increase, or even the 243 heads? It's listed range is 1200 to 6000 rpm.

My first goal with this thread was to compare the LS6 cam I picked up with the heads, versus something more aggressive. It sounds like both the 212/218 and EPS options will be significantly better than the LS6. Now that the LS6 cam is out, I can focus on a new cam either off-the-shelf or custom cut.

I'd like to do it right the first time as Predator-Z said, and not go back in again because I chose the wrong cam. I'd like to optimize the combination where practical, but not chase an incremental 3% improvement for a 50% increase in project cost. For example from Predator-Z's comments earlier, I agree the valve job would be a great idea, especially if the heads needed to be freshened. But I am not sure the extra cost is justified for me at this time.

I thought I'd ask here about my goals & options before giving him a call. He seems to know his stuff from the things I've read.

I've read the stock rockers are best suited to around .550 lift, and the untouched 243 heads don't benefit much past .550 either. Can custom cams simply be cut to a lower lift? Yes, a good question for PatG. I assume a lower lift would be better for wear and longevity.

Thanks for confirming the parts list. The LS6 springs I have would work with the 212/218, but not the EPS.

I agree that every bit will help. Are you also opening up the rest of the incoming air path? If this cam combo is exhaust-restricted and we're using stock exhaust manifolds, would gains on the intake side benefit much? I guess I assumed the biggest bottleneck of the whole loop is the limiting factor. Is that not the case?

I'd love to hear how your build goes with this cam. When do you think you'll be on the road with it for an Sotp impression?

oddwraith

iTrader: (1)

If you were looking for higher rev limits (which cc 212/218 114 low lift doesn't really warrant btw) than I'd have to say to go with a spec'd eps cam. Check with our vendors for details. If stock rev limit, easy tuning, and off the shelf is more your style, the cc xr265hr 114 (mentioned above) will provide great midrange improvements right across the board, but will not do wonders past the advertised 6000rpm. It's not that it loses up top compared to the stocker, but it won't do much better.

PREDATOR-Z

That will depend on the ICL at which the cam is installed.
If it is on a 114+4 LSA (110 ICL) that translates into a 36 IVC and with a LS6 intake, a peak of ~5600/5700 rpm
The 114+2 LSA 112 ICL with a IVC of 38 will peak around 5800 rpm
114 +0 LSA or (114 ICL, ie: straight up) will peak at around 6000 rpm and can carry 500 beyond that easy for 6500 shifts.
In general on a LS6 intake, going beyond 42 IVC is usually limiting the peak at around 6200 rpm. There are other factors but not as important as the IVC.
The intake is the limiting factor.

PowerShift408

iTrader: (44)

It all really comes down to what your goals for the car are. Are you looking for a specific rwhp number? Are you looking to get to a certain e/t goal at the drag strip? Just want a bigger kick in the pants? All these will help determine what the best modification path is.

One avenue that I'd like you to consider is that of a custom ground cam. Many of LS1tech's supporting vendors will go over with you, exactly what you want out of your car, and factoring in what modifications you already have in place, will tailor-make a cam to your needs. I did this with a member named Patrick G and was incredibly pleased with the results.

Darkman

iTrader: (2)

I am running a 218/230 .595”/.600” 116LSA +2 advance EPS cam in a 2005 CTS-V (LS6) with stock exhaust manifolds, high flow cats and other mods. It is a great street cam (407rwhp, 393 rwtq).

99 Blue Bird

iTrader: (3)

I agree that every bit will help. Are you also opening up the rest of the incoming air path?
Yes i am trying to open up the rest of the incoming air path as much as possible. Im going with a Ram Air setup for f bodys, a 98mm air lid, 85mm mass air (actual measurement is in the 9Xmm range), a ported TB, and a ls6 intake. ill go with a fast 90 or 92 setup if i find a deal on one.

If this cam combo is exhaust-restricted and we're using stock exhaust manifolds, would gains on the intake side benefit much?
Yes they will. The cam is designed to force air out of the restricted area. Thats y the duration split is so wide. It builds up more air and forces it all out. Not saying the manifolds are not a restriction, just saying the cam is cut to overcome that restriction as much as possible.

I'd love to hear how your build goes with this cam. When do you think you'll be on the road?
Hopefully in November. Money has been the factor for me on this build.

99 Blue Bird

iTrader: (3)

Also here is my mod list

AI 226cc CNC Heads
LS6 intake and PP TB
Fast Toys 98mm Air Lid
85mm Mass Air
Fast Toys Ram Air
Powerbond 25% U/D Pulley
Custom Y-pipe with a Magnaflow or Flowmaster Merge
Magnaflow Catback

like i said im just hoping it runs in the low 12s high 11s and puts down some nice trap speeds. should be a nice sleeper and i should fool some people and catch them by surprise. and most important it will pass smog.

bartmanC5

iTrader: (3)

Yes, no, yes. HP/TQ less than 500, fully attainable. The stated goal is actually a front seal swap. I'm generally pleased with the performance, but would like "more power" while I'm in there. Yes, kick in the pants pretty well sums it up.

Now that I've ruled out the Z06 cam I have in-hand with the comments here, that is where I'm headed. I'll get with Patrick next week, and hope to be another pleased customer.

I don't understand half the implications of cam selection which is why I'm all over the board with my questions. Having a 1:1 conversation with an experienced person will get thru that, and to the turning-wrenches phase before snow flies.

Thanks for the info, oddwraith. It's been helpful.

My questions here are leading to a better understanding of what tradeoffs should I expect about the area under the curve? You can have monster low & mid torque -or- high peak hp -or- a moderate bump across the spectrum? Is this true with all cams, or can some excel at 2 of the 3? All else being equal except cam, is the area under the curve a relatively static number and you must take away here to add there? If so that answers my question (you gotta pick 1).

I understand you can increase the area with more cubes, intake & exhaust improvements, etc. I suppose cam selection positions you better to take advantage of those upgrades. Just thinking out loud.

Nice. Sounds like EPS has many options that would fit my bill. Can I ask what power range you notice that is attributable to your cam? Do you happen to have a dyno graph you could share?


In any event, I'll post back with Patrick's recommendation and eventually a before-and-after dyno result.

Darkman

iTrader: (2)

Attached.

bartmanC5

iTrader: (3)

Thanks Darkman, very pertinent. Interesting to see how a different LSA and advance for the same cam work out. I overlayed your graph with the one referenced above and it looks like your HP carries out flatter past 5500.

Since you were coming from an LS6 cam, how would you compare the two? I found a stock '06 CTS-V dyno graph to overlay, and the EPS looks to give a solid 30 or 40 lb-ft from 2500-6600 rpm, and still some gain even at 2000 rpm. Looks like a total "win" with nothing lost thru the whole range. I'd imagine it is a world of difference from the stock Z06 cam.

Definitely calling Patrick this week.


Good luck wrapping up your build. I'd be interested to see your drag results with this cam and your mods. Unfortunately the closest strip is about 3 hours away from me, so can't just hop over there. Not to mention zero experience.