Hahaha. Tony has been preaching about Airspeed on here for a long time!

 

I've got stock 706's on my LQ4 with LS3 Flat tops. It's just something simple I slapped together there wasn't really a major goal in mind , I needed to get it rolling again and I knew I needed to put a solid short block in my car so I'd have a good foundation down the road once I figured things out a little bit better I knew that was the best way to start and my only regret at this point is not fly Cutting the Pistons or getting Pistons with fly cuts in case I got the itch to go all out. I should remedy this and when I do I can replace the heads with another set of stock castings that I have already like you do. I got 241s or 706s. I'm leaning towards home porting The 706 is a little bit to see the difference for science but in all honesty I'd rather open the hood and see some really well worked 241s were they belong

Choose whichever cathedral port head you wish and build the cam to complement the rest of your setup

I know for sure though that there are better mid-range numbers to be squeezed out of my less than ideal combo as it sits if I could decide on some nice cam events for it with the flat tops and the rest of the restrictions it still has a lot of compression and the potential for even more mid-range than I've seen with the cams I've ran like 20-80 tq -hp right!? even with the LS6 intake still on it and restricted exhaust I would happily swap cams on it again to see that happen.

I've tried 4 different cams so far messing with it the setup so far the car is like a rolling cam challenge at this point so throw me your ideas


​​​​​I've ran
212/218 115+0 really good
226/230 112+4 only better than above after 5k noticably worse lower end even Though both cams share the same IVC close event at 0.006" and 0.050"
204/222 112+1 quietly ripped to 6k and then fell flat, I was getting happier but needed wider power band
Then I tried a custom spec by yours truly comp
220/224 115 -4 (yes minus 4 degrees that 119° intake center line and a 111° exhaust center line rocket and roll, because I got wound up in y'all 's dynamic compression calculations This cam produced a perfect 76 IVC @ 0.006" for 8.5:1 dcr calcs and really responded to mid-range timing advance

If You've gotten this far I see now that with the 1.89" intake valve My ideal " single plane" LCA is probably about 105° or 105.5° if we are talking race day But I need something more like the op mustang grind for my setup. That's insane. The power that made was with only 12° of centered? overlap. @ 0.050" ?! Is this correct? I'm trying to find the right middle ground there that's less exhaust overlap than the summit single plane stage 2 cam 227/239 108 LCA but I've also ran the comp 777 drift in an lq9 setup I used to have that was a 233/243 114+5 and that was really great too and a lot less overlap but that setup had really good exhaust. I'm running a more restricted exhaust on this one



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Let's hear more about this earlier E/C with full exhaust

 

That 204/222 112+2 is one of the cams Im considering. With your displacement and head combo, Im thinking a head swap would help extend your rpm range past 6k a bit.
On that same note, Im wondering about having the 706s machined for 2.0 valves along with a valve job. Then I can swap the intake valves from the low mile 241s I have. Then I can hand blend the valve job and leave the ports alone.

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I think you should consider the Summit Ghost Cam 8715 (222/234, .600, .575, 115+3) or the Summit 8720 (218,227, .600, .600, 112+2). I am considering these two for my 04 gto. It depends on whether you want more power in the low to mid range or up high. Ghost cam is good everywhere in that you keep stock power down low and add to the top end. The 8720 would help everywhere, but less on the top end. I am leaning towards the 8720 personally.

 

​​​​​THat cam rips it would definitely benefit from better heads on a larger displacement combo

 

I could really probably use something in between the 5/4 race cam 218/230 105lca and the torkinator 212/218 110lca for this setup with the stock heads and restrictive exhaust, still I'm going tighter LSA this time I I've had the durations all over the place so I want to try at least 110 or tighter this time call me what you want I've had two 112's and two 115's in this one alone and over the years I've had 112-113-114-115 various durations various displacements this one needs a bigger overlap triangle but do I need the earlier evo or not to get the job done I wonder and has anyone ever tuned and dynoed a comp thumper cam? I looked up the cam card on the 235 /249 - 109lca +5 advance it's looks like a lot of fun actually

 

OK I am surprised you wanted the lower lsa considering the 226/230 112+2 cam was weak below 5000 and because you liked the 220/224 115-4 cam.

Well here are two great ones for you:

Little Chopper LS Camshaft (222/232-108+3) - Cam Motion

Lil' Lope LS Camshaft (216/224-108+3) - Cam Motion

 

The 226/230 112+4 was noticably weaker vs the 212/218+0 below 5k 212 is always really good street cam hard to beat

but my 220/224 115 -4 feels better than the 226/230 through the mid-range and pulls cleanly out to 7200 where it feels like it would happily keep going I have it lined with a 49° versus 41° intake valve close vs the other two cams rips out to 7200. Compression is fun it's not perfect but it works
The 204/222 112 was hands down the best from idle to 4k or 5K rpm but it couldn't breathe anymore by 6k and I need 7k
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I've about settled the 108 LCA 105 ICL is great though it should work even better when I upgrade the cylinder heads appropriately you guys pick the durations for the compression it's not about the idle note it's about mathing the best that you can for the combo to have as much of it all in by 2500 and keep it there till at least 7k which it seems like a lot of the cams built for "sound" appear to do maybe the durations need adjusted a little bit for my setup I don't know But I'd like to avoid as much of the " idle note" as possible

 

Maybe the auto trans wants a smaller cam or more rear gear. I don't think my BTR stage 2 with a M6 is weak below 5000 rpm even with 3.42 gears.

 

Little Chopper Cam it is.

 

@stockA4
So... 4.065 bore 3.622 stroke 6.098 rod length? Flat tops?
Whats your SCR? I'm back-calculating ~11.8:1 with the 76 IVC. Is that correct?
What's the details on this "restrictive exhaust?" (from heads to tailpipe).
What intake and throttle body size?
Are the 706s ported?
What's the current cam not achieving that you'd like it to do better?

And, this is an extreme example of comparing a restrictive exhaust (especially since it's mid-lengths and a stroker) with a cam meant for open headers; then going to a cam that matches the complete setup. But it illustrates how the combination is important. (See post 24). The cam with less intake and exhaust duration, and wider LSA in this case made more power across the board and allowed it to actually climb far higher past 6k
https://ls1tech.com/forums/generatio...ig-guns-2.html

Depending on the total setup and goals, maybe what you really need is a jr. version of a Big Gun?

P.S. Don't get me wrong, tight LSAs have their place and I'm a fan when it makes sense.

 

68formula,

Thanks for the interest in my setup. Let's see if we can Maximize The airflow potential here.

It's a lowered 4th gen Camaro 2600stall 4L60E 2.73:1 26" tire I use the car mainly now For SCCA CAM-T autocross competition where I leave the car in first gear for the entire run where I reach speeds over 60 mph the car happily does this in first gear touching 7K occasionally between corner transitions and The current cam I put together works really well here It has a fairly smooth idle dialed in at 800 however I just can't see how my 115 LSA " minimum overlap" compromise is "ideal" giving the math of my engine wants lots of overlap due to the small valves and ports but it also has a lot of compression I thought I needed to minimize the overlap so when I did this cam (220/224 115 installed -4) I called comp and told them I needed a "Band-Aid" lol They wanted to give me a 230/242 112+0 I thought I could do better But maybe I was closer than I thought? I mean the exhaust on 111° is the same as a 108+5 right I was just trying to pay attention to the restrictions on the intake side with the 119° intake center line. Lots of stock cams are around 122.5° intake centerline, it worked a lot better than I expected but I know it's capable of more mid-range the 204/222 112 +2 was excellent there I just needed it to hang on or at least carry a little bit longer

Yes, you are correct sir It is 11.8: 1scr
Simple smash together of stock parts. I only want to see how much air flow this stuff smashed together is capable of with the right cam and ignition timing on pump gas

Okay, here we go
Let's follow the air all the way in and all the way out

air goes in...
SS hood +FRA?
Fram air filter
Whisper airlid
Stock maf with screen
Ls6 intake stock 78 mm throttle body stock 02 injectors
255 pump (car maintains safe AFR between 12-13 probably due to the tall gearing LOL)
Stock 02 castech 706 heads 61.15cc 1.89" intake 1.55" exhaust valves
LS6 springs BTR 7.450" pushrods
fel pro 0.048" gaskets
Lq4 with LS3 Flat tops 0.005" out 376ci
11.8:1scr

Air goes out...
Stock 02 f-body manifolds
2 -1/2" Y pipe
3" intermediate with a 3" open cutout for competition
2-1/2" inlet Walker quiet flow muffler and stock tailpipes when the cutout is closed on the street

 

Seeing as how youve tried several cams with various results., my take away is this. You have a "larger" motor at 376 inches. The bottle neck in my opinion is the stock 706s. While I agree they do provide good low and mid range power, I can see them limiting past 6k. Not saying you need a full CNC job, but some improvements would really help it carry past where it is now. Some 2.0 valves, valve job and blend would be a night and day difference.
W What did you say the static compression is now?
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Both the stock 706s and 78mm TB are holding it back. Getting the heads ported would make a world of difference though as you said. Then there's those stock exhaust manifolds.

 

So you were running all those cams with that compression? Or those were ones you've tried on similar combos and you're just pointing out the powerband differences? Seems like some of them wouldn't play nice with pump fuel without pulling a few degrees of timing.

Oh, and what springs are you running?

 

Yes I ran all these cams ran the exact same setup year round accept timing yes I ran the 204/222 112+2 with the least total advance 22°, I think it was and it was fine in the summertime on the hottest days It would get a little irritated if lugged under 2500 RPM though that was a stock '02 A4 Camaro timing map though just added a few degrees after 3k on it and the car still had the stock converter in it at the time It wouldn't have been a problem at all if The car had had the 2600 converter in it It has in it now. With the 220/224 115-4 I'm running a lot more timing like the earlier LS maps look It and I recovered a lot of the response I lost with the IVC going from 33 to 49 (look at the valve events between the two cams, the biggest difference is really only the IVC now my total timing advance is 30° with a little bathtub dip to 26°- 27° at 4K rpm The compression really just messes with the timing advance at idle. It's very sensitive to slight changes in the timing at low speed and with the stock dbc setup It needs no more than 16° in gear for stability with the looser converter no matter what or it will try to surge even if the cam has any overlap or not it's really I believe I messed with the over and under settings slightly as well to keep it happy but of course it's also happy to coast and cruise at 40° as well so it's worth it. Still in my opinion because it still gets decent fuel mileage. Not really any worse than my stock 6-speed to be honest we're just splitting hairs here. Wondering if there is a better match of duration and center lines for my combo thats all what would happen if we did something like a 224/244 108+3 what would happen remember 2600 verter big cube small port we still talking a drag race 0-60 to be exact it just has shorter turns between rounds hehe

 

when are the new cams coming and can you tell us anything about them?

 

Great info. This also tracks what I expected. I'm actually surprised you didn't start with the SDPC LS6 Powermax Plus with the compression ratio and targeted powerband, but I'm guessing maybe you had concerns with stock converter. That would have been a much closer fit with the proper converter. You're current cam is very interesting being 4* retarded, but with your setup, does make sense that it works better than one would initially think. Anyway, what you're seeing with the super high DCR with the Powermax and timing changes with the other cam, you crossed the tradeoff point where you have to pull too much advance timing to keep from knock, that it loses performance. Whereas with a slightly lower compression (like with 243 heads) would allow a couple more degrees and make more power (plus added flow)

I think I know what you're trying to achieve with the couple of 108+3 ideas you've put out there, but for your setup it's actually going to backfire (no pun intended). Definitely take a look at that link I posted earlier to another LS1Tech thread, and also the link within that. It should clarify the picture.

So with all that I started with your current specs. and then kept making adjustments:
I felt it needed both a little more intake and exhaust duration. You mentioned the two cams with same IVC @ .006, & .050 behaved very differently. That and your current setup seems to indicate the setup likes the E/O around mid-40s. So I left it the same at first and only changed the E/C to 3* (to start). That would be close to avoiding exhaust reversion, and still some OL to use the exhaust pulse to help the start of pulling in fresh air.

I thought maybe trying a little above what I'd normally be comfortable with on DCR based you what you said, would work okay with proper tuning. So I figured allow up to 9:1 (which worked out to 69*+). Since this would be a totally custom camshaft I used a CamMotion intensity of 55. That put the IVC @ .050 42.5*. So I punched in 43*. On the IVO I wanted to keep it <0 to not contaminate the intake charge at lower rpm/loads. For that I used -1*.

Together all this resulted in a 222/228 111.5 -0.5. Which seemed really close to a good setup. But with your particular exhaust, I was still concerned about reversion. So I bumped the ICL/ECL to 112/112 (112+0) resulting in a 2* EVC and bumping the EVO to 46.

I played around with it some more adding and subtracting a degree to the durations, mild tweaks to the ICL/ECLs. I finally settled on 223/228 112+0. This results in IVO 43.5* IVC -.5*, EVO 46* EVC 2*. A little more intake/exhaust duration, some 5th cycle effect, yet avoid reversion so it stays strong above 6k. It'll work well with your converter too.

You never mentioned what springs you have, but if they're .660 duals, I probably do .595/.612. I don't know if Comp has some lobes close that would fit, but they typically have closer to 50-52 intensity, so you'd have to adjust a little.

 

68formula
I had a feeling when I pulled out the 226/230 112+4 it would have been noticably better straight up 112+0 for all the noise it made this makes sense keeping the overlap @0.050 0° or close to it if the intake overlap hurts it that much. I'll think on it