For me, anything much bigger than the 218/228 with .525/.525 112LSA on the hot cam would be too big for daily driving. Of course I'm working on the tuning still, but ya know.

 

Hey, don't get me wrong - I agree with you completely in theory - camshafts are all about trade-offs in some form or fashion (be it idle, power, octane tolerance, valvetrain longevity, etc.) I just disagree with setting a general XXX value and saying everything above that is a race cam, etc. Like you pointed out, it's all about tradeoffs, which makes any specific breakpoint inherently invalid.

We have done camshaft setup's, especially a few small solid's, that imho idle better and are smoother than stock. (going by idle vacuum and emissions as well as percieved idle quality). You could also take one of the tiny cams, grind it on a 110 install it straight up and get a good bit of "lope" to it.

Just as a general point a large amount of cam "lope" perception seems to come from the exhaust itself. I can take a person and stick them in a stock LS1 with a cutout and then a LS1 with a 216/216 grind through a stock catback and they will generally think that the car with the cutout is "Cammed" while the other is stock.

But anyway, I do agree with you in theory, and every person has different perceptions - I do think.

Have you ahd your car dyno tuned though - I really am suprised that you would get "lope" from a 212/224 camshaft in a 415, though I admittedly do not have much experience with the TPIS grinds - do you happen to know the LSA and intake centerline?

 

This camshaft recommendation 'thing' is always a cam of worms. Whenever questions of this type are posted, there are always lots of differing opinions and advice, all well meaning I'm sure.

Here's my thinking.

When I read the initial post, I noticed immediately that the author has used bold type when writing the word 'driveability'. This indicated to me the importance he, the author, placed on that particular quality. So my comments were directed toward what "HE" thinks is most important.

So, if DRIVEABILITY, is the key operating word here, we need to try to understand just what that means to HIM. Not being able to read his mind, I made certain assumptions and based my advice on the following.

First, take a look at the duration of factory camshafts; those that are delivered to the showroom floor, not the aftermarket variety like the HOT CAM, ZZ whatever, etc.

I think you'll find that none ever exceed 220 degrees in duration at .050. Not even the most high performance models available today. I mean, Z06, Viper, etc.,; none have cams above 220 degrees duration at .050.

Now, you must ask yourself "WHY?"

There are many reasons for this, CAFE, emissions, warranty and, yes, driveability, among others.

Grab any of the big cam company's catalogs and take a look at their offerings. You'll notice that the wording used to describe the characteristics and recommended requirements begins to change when cam duration approaches and crosses that 220 duration level.

You begin to see the "Basic rpm operating range" hitting 2500+, higher stall converters begin to be recommended, the use of words referring to "fuel economy" are missing, idle characteristics begin to show "fair", on and on.

So the trick is to take their recommendations in general and not to "nit-pick" each and every word. What you can't escape, though, is the sense that once you move above 220 you are into performance cam territory, leaving behind "fuel economy", "good idle" etc.; qualities which are found in cams below that number.

BTW, I did not say or intend to indicate that cams above 220 are "race" cams. While not always as precise as I should be, I do try to choose my words carefully. I long ago learned that on this and other boards, there are lots of counter-punchers laying in wait.

Of the four events in a four stroke internal combustion engine, it's the intake closing point that has the most dramatic effect on power. As duration increases, that closing point becomes later and later. This, combined with overlap, creates the power gains and also causes the disagreeable qualities of a long duration camshaft. The longer the valves are held open, the higher up the rpm band the best power is made.

These disagreeable qualities can be partially offset by resorting to a wide LSA and/or installing the cam more advanced. BTW, I don't believe in installing a cam differently than the card recommends though. My feeling is that if I need to degree one in at 6 degrees advance, rather than the 4 degrees called for on the cam card, then I really need a shorter cam.

If you opt for a cam above 220, you've got to be prepared to make all the other necessary mods required to make it work right. On a TPI engine, you'll definitely need a custom PROM burn with raised idle speed, fuel and spark table mods, etc. A higher stall converter may be called for too, among other things.

Bottom line, if driveability is truely your primary concern, stay in the range one step higher than stock and choose a cam with less overlap.

Hope this helps.

Jake

 

I think I have a little experieince on this one....read my profile:D , so I'll just chime in :)

My 383 stroker, self-ported and polished heads, GM Hotcam Kit incl. 1.6 RR's, etc. can really give you a kick in the pants when your in-the-mood :crazy:

But otherwise, she makes a great daily driver....I drive roundtrip 86 miles to and from Manhattan each day and would't have it any other way :jester

The car runs really smoth and docile until you want to kick some butt ;)

I would recommend you talk to Frank Fernandez though on upgrading your tranny (if it's an automatic) if you are going to stroke your powerplant. A 383 kind of overpowers what our original Chevrolet designers put in the car....just a word to the wise :D

Good luck on your project......you'll love the upgrade :cheers:

 

Once you go above stock though you make tradeoffs. I don't disagree with everything you are saying, I just disagree that there are magic numbers like 220, etc. that themselves tell you all about idle quality, etc. I could take a 220/220 116+6 camshaft on a LT1 and I bet you may have a hard time telling it from stock. At the same Time I could stick in a 212/212 108 -4 camshaft and it would probably have a pretty healthy lope to it.

I just disagree that you can say above XXX duration this cam isn't something to consider - there are just too many other variable. You could take 2 cams with the same exace specs @ 0.050" lift that had very different idle qualities, performance values, etc - due to other factors like lobe profile, intensity, etc.




Looking at the intake valve closing - yes, increasing duration delays it - but so does a wider LSA. So if we increase the intake duration and narrow the LSA you can end up with an intake closing in the same point. Or you can adjust it by advancing/retarding the entire camshaft. ETC. It's all related, and duration @ 0.050" is just a small part of the entire cam setup, and that's why I don't think you can make sweeping generalizations based on it. You even pointed this out yourself below



The cam card reccomendation is pretty much generic though. If you look at any off the shelf grind they are almost always 4 degrees advanced. This really can't be perfect for every camshaft. An in actuallity it's all relative (and so somewhat irrelevant to assign a number to it and say "this is good". What we are really concerned about is the valve opening and closing events - and as we pointed out above these are affected in many different ways.



I think that might be one point of difference - this is a LT1 engine and it doesn't have nearly the problem with reversion on longer duration camshafts that the TPI setup experiences.

I do agree with most of your points, I just don't agree with the conculsion (qualitative judgement). I just feel there are too many variables to say 220 degrees intake duration is the breakpoint, etc.



[Modified by ChrisB, 2:20 AM 2/3/2002]

 

The ZZ9 and LT4 hot both have a bit of a lope at idle. I've also heard of tuning issues of an LT4 hot cam in a 350 cu. in. cars with automatics. Shalin turned nearly identical dynos in his blown 355 with the ZZ9 and LPE 211/219. The LPE cam does idle a bit better.

My friend with the MORE 383 initally used ported LT1 heads and the small cam 215/224(?) MORE uses. He was happy with the work but knew afterwards he picked to small of cam. The car was converted to ported LT4 heads with the 222/230 and the car was an auto. He works computer tech support driving location to location all over north Georgia and this was his daily driver. Duration #'s aren't everything. Ramp rates and cam advancements can have a huge affect on idle.

If you want a bigger name tuner to do the car. MORE would be my first choice. I would probably get a 383 with Stage 2 or 3 heads and the 222/230 cam. Also get a road race oil pan on the car. 96CELT4 can tell you locally about autoxing on the stock pan and the car not getting enough oil. MORE also had pics of long tube headers with random tech bullet cats that looked beautiful. Long tubes are the way to go. Talk with MORE tell them you're goals and they can work with you. I think you would be really happy with the work they do. I don't like a forced induction 396 the rod ratio suffer and the rings are further up in the pistons. However on a NA motor it shoudln't be a problem, and last a very long time.

I still think locally you could have a motor that is just as driveable built locally by Grimes, Elite, or Barnett cheaper using cam and heads from Speeddemon. Grimes and Barnett have been around for ages. Then have Jeff at Thunder install the motor. The biggest issue would be tuning the car because of the OBD2 computer. MORE maybe the closest shop to tune the car on a chassis dyno and burn a custom program. But I understand your concerns with that route.

 

The folks at Speed Demon seem to be good people. I have talked to them before and have bought some stuff there aslo. I also have had several dealings with MORE and I know the owner Mike. I have been there numerous times and can say that they are first class folks. If I were you, I'd go for the 396 LT4 package that will still be very drivable and pass smog tests if you have to. If you ask me, companies like LPE have lost touch with the average hot rodder. Companies like Speed Demon and More are much more customer oriented even it your not spending $40K on twin turbos!

Jason

 

Just to add my $.02 here let me explain my situation. I have the LT4 Hot cam in a stock displacemnet LT1. It has a noticable lope but it doesn't shake the whole car. Kinda a nice mild wooga wooga. One thing that greatly affects idle quality is idle SPEED. Mine idles around 800-900 and is completely driveable, will idle ALL day long without touching it. Now I have a friend who things it should idle around stock. To him it doesn't sound right because the car doesn't try to die on every lope. What he doesn't realize is that if I did it that way, I would basically have to coax it up to where it would run before I could give it any real gas. Sure it sounds meaner, but it's really counter productive.

I think mine idles about perfect, it's a good tradeoff between mean sounding and smoothness of operation. My car sounds aggressive, not like it's going to fall apart. Then again, this is where the difference of opinion comes into play. I want people to know I have the cam, and all but the dumbest ricer knows what that wooga wooga means when I pull up beside them.

I have some sounds.
http://24.17.202.123/sounds/hotcam1.mp3
http://24.17.202.123/sounds/hotcam2.mp3
http://24.17.202.123/sounds/hot_cam_open_headers.mp3

It has a fairly healthy idle to it, but still maintains excellent off idle throttle response and everything works, no vacuum problems at all.

 

WOW.

Really got my money's worth out of this post! :D

I've been studying your posts for a while now, and making some notes. I should have been more clear about my goals, but didnt want to interrupt your posts. My ultimate goal is a stealth stroker LT4. I mean an engine with behavior qualities identical to stock form (idle, smooth acceleration)-just ALOT more power. But, like I said before, I would be willing to trade some HP#'s for driveability.

If driveability is all in the camshaft, I'll choose one with stock (or better) qualities. Don't want to have to adjust the idle RPM's to hide any lope, so I'll need a less aggressive cam. I'll take a print out of this post to the tuner, and let them decide the best cam for the job. I'll get the full stage 3 port job on the heads, and keep the stock 3.45 gears. Hopefully this will bring about a very well behaved thoroughbred.

What about an oil pan? Being that this is my daily driver, and will never see a drag strip, would a racing oil pan provide any benefits? I'll probably take the car on a road track once or twice a year, but other than that, I generally stay out of the upper RPM range. This might be the best time to do it, if it would help.

Thanks again for the posts!!
:cheers:

 

While we're talking about idle characteristics, does anyone have any sound files of a stock displacement LTx with a CC306 cam?

 

[SNIP]WOW.

Really got my money's worth out of this post! :D

I've been studying your posts for a while now, and making some notes. I should have been more clear about my goals, but didnt want to interrupt your posts. My ultimate goal is a stealth stroker LT4. I mean an engine with behavior qualities identical to stock form (idle, smooth acceleration)-just ALOT more power. But, like I said before, I would be willing to trade some HP#'s for driveability.[SNIP]

". . .behavior qualities identical to stock form (idle, smooth acceleration). . ." Well I guess this should pretty much put all the differing views to rest.

[SNIP]If driveability is all in the camshaft, I'll choose one with stock (or better) qualities. Don't want to have to adjust the idle RPM's to hide any lope, so I'll need a less aggressive cam. [SNIP]

Well, not "all" in the camshaft, but cam selection is the biggest part of it. If you chose a stock spec cam, but installed a set of heads with really big ports, then many of the disagreeable qualities would surface, just as if you'd chosen a long duration cam with stock type heads.

I once ran a CompCams 218 @ .050 Hi-Energy flat tappet hydraulic in a 468 BB but installed big port aluminum heads (315 cc intake volume) and the big heads caused loss of low end manners. Ran like the wind up top though.

I'm betting, too, that if you go one step up in cam duration you're going to have to raise the idle speed. I don't believe a split duration cam in the 210/212 intake duration range will idle with stock-like smoothness at 650 RPMs. At 800 or so, the cam should be "just noticable"; that is, a sharp ear will be able to tell you've got a cam in the engine.

My 415 is set to idle at 850 with BLM and with Integrator values of 126/128 and you can definitely tell there's a cam in the engine. At 650, it's Rickey Racer sounding. The ZZ9 does have longish exhaust duration though.

I even swapped half of my 1.6 CompCams Pro Magnum RRs for eight 1.5s with a guy on this forum. I put the 1.5s on the exhaust to decrease the intake/exhaust duration spread and idle quality improved noticeably.

Sewing machine smoothness and camshafts with longer duration are mutually exclusive unless you go really, really BIG in the CID department, then the cubes mask the cam.

Keep us posted.

Jake

 

That woudl be pretty nasty. I have a friend with a CC306 in his 396 and it's VERY noticable. On a stock 350 I don't even know if it would idle worth a crap.

 

OOOoooo... jet an e-mail to SNKSKNR .. he has the 306 in his LT4 (355cid) .. with 13.5:1 compression :crazy: :crazy: :crazy: That thing is LOUD AS HELL and the cam nearly stalls the car any time it's stopped without a little bit of throttle.


[Modified by Glock'94, 3:51 PM 2/3/2002]

 

Yep, I agree with Jake then on the cam choice - or the general vicinity. It will still depend somewhat on what size motor you go with, etc. (383 vs 396) but if you want it honestly indistinguishable from stock then the duration is going to be down there. The lingenfetler 211/219 camshaft (but on a 114+4 )would probably be a good choice for you.



Yikes, I would work on the tuning a little bit. I will post some video of my car (350/cc306) later on today - no idle issues at all with the AC on or off, etc.

 

Love the sound of the CC306. We were over at a local shop with my Dad. A customer had an LT1 Z28 with long tubes, atr catback and stock heads running the CC306. Dad loved the sound said it reminded him of his old 13:1 327 with sidepipes on his 67 Vette. I don't think it is what Ross is looking for though. ;)

The CC305 or Crane 222/230 I think would sound really mild in a 396. The 211/219 would sound just about stock.

 

Http://www.slowcar.net/shared/car.mpg

there is a short video of my camaro with the cc306 in it. Stock bottom end. Idle is set at 1000rpm, but tach is about 150 high. The video clips are with the AC on. It idles well from a startup, and when I come to a stop, as well as driving around the parking lot (power steering pump putting a load on the car).

Exhaust is catless 3" y-pipe with 4" mufflex.

 

Had the ZZ9 cam in my 350 and the car idled like stock, drove like stock and could be nasty at the track at the same time. Have the ZZ409 cam in my 396 and the car idles like stock, drives like stock and hope to be nasty at the track at the same time. Be careful with sound. There are alot of mustangs that sound bad that are running in the 13's. JMHO.

 

Have put your on the 396 on a chassis dyno with the ZZ409? What did ti turn?

 

:confused: :confused: :confused: :confused: :confused: :confused: :confused:

 

Similar set ups have dyno'd at 410RWHP/422RWTQE with the ZZ409 cam 30# injectors and 58TB. Still breaking in the engine with the stock injectors and 52TB and trying to get the timing set right. Best so far is 385/411. Will be adding 30# injectors. Current fuel Pressure is at 53.