So, I cant keep my wife from vacationing away our spare income so I haven't had anything to really do on my car since I finished my H/C/I set up. That being said, I thought I would spend some of my spare time learning more about cams and have started working my way through the stickys on the subject.
When I started this car I consulted Martin Smallwood about my goals, etc. and he recommended the Tick SNS Stage 3 cam and TFS as cast 220 heads. After hearing some other options in my budget and speaking to Martin some more, that is what I went with. I am tremendously happy with those choices and really enjoy the car when I choose to drive it. I paired all that up with the basics.... 92/92 set up, AR long tubes, Magnaflow cat back, appropriate fueling, and a S60 w/ 4.10 gears, etc...
I got it all put together and brought it to Pat G in Victoria for tuning. Again...really happy with the outcome.

Where I get a little lost is that I read a lot of posts where people are recommending folks run a "smaller" cam for low end torque and I get a little lost with that recommendation as I feel like my car has plenty of low end grunt. My cam experience is limited to this cam (235/243 .630/.610 111+2), a 224/224 in a different car, and a blower cam from Thunder Racing on a PC car wayyyyyy back in the day that I cant remember the specs on. I have even had folks comment that they thought the SNS Stage 3 was a little large. Just looking to learn, not change my set up. Like I said, I really like it. Is there a cam that you think would preform better as just a Sunday driver/street car/ rare trips to the track? I feel like the one in there is a pretty good balance between some low end torque and pulling pretty hard up to 6800. The car screams under WOT. I attached my Dyno sheet from the tuning with Pat in Victoria to reference (Mustang Dyno). I thought it may be relevant and may help you educate me. Drop some science on me if you have a few spare minutes...

Thanks Fellas

 

Being that you have 4.10 gears and a manual I think that cam is a fantastic fit with those heads. The 4.10's help to compensate for the big cam down low and then you have awesome mid range and top end. Your setup is really good IMO.

I have 4.10's and a 6-speed with a cam very similar to the SNS 3 but with PRC 5 3 heads. I love it

 

Thats with my 222/228 on a 113+4 .567 .567
Longtubes, magnaflow catback, ls6 intake and stock 799 heads with a 278mm CircleD budget converter. Clearly you have more top end while my mid range is much better. (In regards to the power curve itself, not the actual numbers produced) You make more horsepower.

With similar heads my torque output would outperform yours. Although I would still make less horsepower.

Your combo is much peakier. Mine is flat. So one would assume mine would be fun for a circuit track or canyon runs. Yours will be fun in a straight line.

 

To be basic. Its not that one cam is better then another. They all have a specific purpose. The valve events, which are what dictate the duration we see when browsing cam catalogues, will give you an idea of when the engine will make power, stop making power and how much valve overlap it will produce. Keeping the intake valve open longer (biggerintake duration number) will make more top end power because more time is allowed for the cylinder to be filled with air moving at what we hope is a high velocity. Provided your lift specs for heads and cam are matched right. You loose bottom end power because of poor cylinder filling and what is known as EGR. The exhaust gasses go right back into the intake, causing poor air fuel mixture quality for a terrible burn and everything is also much hotter. More overlap is not suitable for low rpm because of the same directly related reasons. But this effect is good at high rpm because volumetric efficieny at high rpm is better because exhaust gasses pull intake mixture into the cylinder faster allowing for a cleaner better burn. And the intake centerline also change up where engines make power. Typically you will see cams with 112-114 LSA grounded with a 3 or 4 degree advance for an intake bias for more low end power. So my cam has an LSA of 113 with a 109icl and a 117ecl. LSA is determined by adding the centerline and dividing by 2. Advancing a cam opens the intake valve sooner, hence why it builds more bottom end torque and chips away at the top. Retarding it does the opposite. Something else to understand is lobe intensity. Ideally you want a valve to open and close instantly. We cant do this yet but the faster you can do it, the better for power. Although its also harder on the valvetrain so there is a balance of power to be had but its ultimately your choice. Thats just a few basic things to know. There are many good reads of you google it. Isky cams has some insight as well on their site about their research.

 

Thanks for the input. I do really like it. It's definitely the most fun NA car I have owned. It was surging a lot when Pat did the initial remote tune. Second one after some data logging was much better. By the time he fine tuned it on his Dyno it was pretty much gone. It's really well behaved at low RPMs and screams under WOT. The limiter is set at 7K and pulls up there but seems to be best shifting at 6800 or so.

 

Thanks for including you Dyno sheet. That helps me visualize what you are saying and it makes sense. I think that is where I get a little lost with some of the posts and stickys. It really helps me when I can see what your talking about. I do agree that this cars power is peakier than my my stalled 224/224 cam. I am not sure that this makes sense but this car is more "manic". You are either cruising at part throttle or getting it at full throttle. My other car was not so much that way. It seemed easier to control power output with part throttle. I am not sure if that is a function of the tune or the cam. No canyons here that is for sure, just long stretches of very flat freeway.

 

I get what your saying here.... I think. So another question just to get your opinion. This cam is specifically advertised to be matched with at least 3.73 gears, I think 4.10 ideally. Is that why they suggest the lower gearing....to compensate for the loss of lower end power due to the longer durations and overlap? And the way I understand it is that this cam has a built in advance of 2 (hence the +2) to give it more intake biased. I am assuming, again, that is is to help offset the the loss of low end power due to the longer intake duration and resulting over lap as per your explanation above.. Am I even on the right track here? Sorry if this is elementary....just trying to visualize this in my head.

 

Have you ran at the track with this setup?

 

Nope. Everytime I have tried to get down to Baytown with this car, the nearest track, it's something....kids got sports, or a cub scouts deal, of there is some family thing, etc. It got so frustrating to be honest I just hung up the idea for a while. Got the itch again though....

 

i highly recommend reading the "why LSA doesn't matter" sticky

 

Sounds like my buddy lol. He has young kids and is always involved with their after school activities, coaching, etc...Has a badass built Mustang Cobra but never gets out to use it lol

 

Yep. Same thing. I tried to be involved...coach, be a cub scout leader, etc and I don't mind it, I like hanging with my little dudes. I finished that car over a year ago and think I put 1500-2000 miles on it since then. I'll make it out there at some point. Gotta keep them priorities straight. Need them kids to put me in one of the nice nut houses of I make it that long. Lol.

 

Haha right! The day that a damn car takes a priority over a family member is a day you need to reavalute your life and priorities lol. This is why I never give my buddy ****, cause he's doing the right thing regardless

 

Hi Mike, Im not trying to change the focus of your thread, i want to comment seems like you have a nice choice of hardware on that car, but being a M6 combined with those specific H/C/I, I would of guessed made more power on the dyno..like 460ish, those numbers to me seem more like 243 heads and that cam numbers..YES I know its a mustang dyno and they can be stingy.
EDIT: and numbers arent every thing ..sounds like fun ride!

 

Lower gearing and Stalling at a higher rpm help cars with larger cams maintain their optimal powerband. As with anything if you recieve you also give...so more stall means more slip. Slip generates tons of heat and reduces transmission life. It also begins to widdle away driveabilty. It takes more gas to get the car moving forward, it severely begins to reduce gas mileage. On the unprepped streets, this usually just burns tires. On a track, more stall and properly optimzed rear gear will typically give you better ET and lower MPH. Now you can over stall and over gear as well. Too much gear and the car will drive way to aggressively and will always be loud, perhaps headache inducing on the freeway. But bigger cams need gear otherwise it will buck and surge while cruising, which is also headache inducing. Too much stall will feel sloppy and you will hate driving it. These two things are pieces of a puzzle that need to be matched correctly for not only great performance but also comfort.

Yes your cam is advanced to give you a little more low end grunt. It makes power a little bit sooner and fall off a little bit sooner. (Again do you see everything is a trade off?) No advancing a cam doesnt help compensate overlap. If you were to add 6 degrees of retard into it the overlap will remain the exact same. It will just move your powerband to the right and decrease felt throttle response. Advancing will build more bottom end, take a bit off the top and increase throttle response. Altering when the intake opens and exhaust closes will determine overlap. More overlap will result in poor idle quality and vacuum. Things like AC and power brakes (which as we know are usually vacuum operated) will begin to not work as well. At a certain point, you will need to figure out ways to compensate so that your brakes work...

This stuff becomes extremely complex and you could easily write a 1200 page book on it, perhaps mutiple books with different theories and results. I dont think their is a single person here that could give you all the details, some of it is even kept secret. ESPECIALLY lobe design. But the basics are out there. They are very long reads, I think there is a pdf on google from a university about all this. It gives all the insight to how the 4 stroke engine works and what changing cam profile does to it. Still tough to get any info on lobe design. And of course everyone will tell you theirs is better then the next guys...dont get too hung up on it.

 

Its not like their is a trick to cam selection. Just be honest with yourself. Just ask yourself, what am I using this car for? Do I want a hot street strip cam in a daily? Am I going for more Rpm? Do I want it to be well mannered? What kind of heads am I running? Do I want to change valve springs every 20000 or 80000? Will my heads and intake make power above xxxx rpm anyways? Can my bottom end take that much rpm?

 

Thanks! Pat actually told me before hand that his Dyno generally kicked out lower #than some other in Houston. Not sure why. I wast over concerned with the peak numbers after it was done and I drove it. It's a blast to drive and livable if I get stuck in a little traffic.

 

BSpec, thanks a ton for the insight. I have been reading and to are right, the data can make your head spin. Honestly, I read some of it and when I'm done I feel more confused. To did a great way of explaining that in a way that was easy to understand.

I also get your point about getting a can based on what you honestly want. That what was great about working with Martin. We discussed things I wanted, what I was willing to live with, cost, etc. This is where we ended up. I know I will have to swap springs more often with this cam but I am completely comfortable with that.

If anyone else had anything to add I am all ears....

 

Thanks Darth. I am actually in the middle of reading that one.

 

Think I need to see track times with this set-up. God knows Youtube is only good for idle clips.