I wonder if I'll be leaving anything on the table with that btr stg2 turbo cam.

 

Its ground for Boost . And does very well with boost . Would not run it in an all motor application unless I was going to boost it down the line .

 

Yea no intentions of boost with this car. Not even spray.

 

 

I have the BTR stage 2. IT will buck some just off idle in a parking lot. Otherwise it drives like stock.

 

how much did your car make with it? also what clutch and gears?

 

Summit I definitely respect your cam knowledge. Would you pleased explain how the cam listed above and the Ghost Cam would compare:

​​​​​1. power wise,
2. idle,
3. valve train noise
4. drive ability
5 valve train requirements

to the golden oldies the like:
Comp Cams 224/224 XER .581/.581 lift cam on a 114
and ​224/230 XER .581/.588 lift cam on a 114

That would maybe help some folks like me relate and understand the new big split cams for cathedrals.

Thank you
​​

 

 

I sent you a PM reply this morning. Let me know.

 

Thank you, Summit that's a good explanation.

 

Hi all, hoping to get some advice on this same topic....

I can get an L77 for $6,300 or an LS3 for $8,400 delivered to my joint. In an effort to save a few bucks and to satisfy the "something for nothing” geek in me I'm thinking I should get the L77 and swap out the cam and intake valves and for around 800 bucks in parts I'll have an LS3 beater on my hands.

About my project:
1. I'm doing this as a transplant into a Toyota 86. Therefore completed it should be around 3,000 LBS at most. This is a darn sight lighter than Camaro, SS or anything else you would usually find these engines in.

2. It'll be matched with a TR6060 M10, 3.73 diff.

3. I'm not a very 'revvy' driver. That is, I usually keep my RPM's low. I rarely push it out to redline before gear changes in daily driving. Being in a light chassis with what could be considered heavily overpowered, this issue is going to happen even more I think. That is, if I am already a low rpm driver, I am sure once this project is complete and I have a mountain of power and torque right from takeoff in a light chassis I am going to get to redline even less than I already am now.

4. As I am this low rpm kind of driver, I am mostly looking to get performance gains in the mid to low RPM's. I am not the type of guy who needs to brag to others about the peak power number I got on the dyno. What I really want is enjoyable pull at low and mid RPM, so I am guessing around the 1000's through to about the 4000's is where I'd be chasing the gains???

5. I use the car for about 70% daily driving, 20% spirited driving on backroads on the weekend/evenings and 10% track a few times a year.

6. I don't really like heavily lopey, lumpy, badonkadonk cam idles. I don't like sitting at the traffic lights and feeling the idles shaking the whole car side to side. I don't like taking off in first gear and feeling some shudder and herky jerky. I don't need to rev the engine to impress the girls. I don't want to wake the neighbors in the morning. If I do rev the engine it will be all for my own car **** enjoyment and when I'm driving with the windows down listening to all that V8 glory. So the lopey sound of a cam isn’t really what I’m chasing. Yes, sure, maybe a hint of it, but that’s all. If you never said anything to anyone, the untrained ear would not even hear the difference between cam and non cam. An enthusiast will probably notice though. I don’t want a divorce from my wife who would refuse to ride in it with me because "it's too loud and vibratey" .

7. I'll be doing an intake, headers, exhaust, tune etc whether I go the L77 or LS3 route. Disregarding these items for a second, if just the cam and valves on their own could be netting me perhaps a 50, 60, 70 HP bump in power, this would be enough to tell me the idea is worth it. At 360HP stock on L77 and 430HP stock on LS3 I only really need to make up 70HP or thereabouts to make the exercise worthwhile in my book. If the cam and valves on their own are only going to get me another 20 or 30HP I think I will just forget the L77 idea and get the LS3.

Cam options….
If I'm right, the stock LS3 cam is 204/211 LS 117. If I am trying to make up some ground from the L77 to the LS3 I would guess popping an LS3 cam into the L77 would work, but I could probably do a little better for power gains whilst still retaining a smooth ride with a cam a little hotter than this.

I could consider popping in an LS9 cam with 211/230 LS 122.5 but this seems a bit odd to me in the quite wide lobe separation. Also this is for a supercharged 6.2 so I don’t think it would be very appropriate for a NA 6.0. I could be wrong though.

Another off the shelf Chev choice could be the LS Hot Cam 88958753 with 219/228 LS 112, but I would be a little concerned the separation is a little low and might end up too lumpy idle for my desires. Also it is a bit pricey.

So that said, I was otherwise defaulting to the Summit 8715 stage 1 ghost cam at 222/233 LS 115+3 . However now that I have been reading and researching a bit more over the last few weeks I am worried that even this might be too aggressive for my desires. Or maybe I am over-thinking it? Perhaps with the right tuner I can still get the ghost cam to where I want it to be in the idle and take off and low to mid torque profile?

What do I think I’ve learned about cam specs in regards to my application, desires etc?...

Lobe Separation: I should probably be looking at higher than lower. E.g. around the 115 (or more) range.
In. Duration: Probably around the 115 to 120 mark.
Ex. Duration: I'm guessing around the 225 to 230 mark.

Are these the major specs/numbers I should be considering for this decision? Should I be digging deeper into the other specs? Am I over-simplifying it by only considering in/ex and lobe sep?

Two more ideas...
1. Cam Motion Mild Performance LS Camshafts 03-01-0005
This thing is 216/226 LS 116.

2. Use a truck camshaft? I am guessing this might give me the low/mid RPM bump I am looking for? There seem to be a number of them in the 210’s/220’s mark, but perhaps there is something about truck cams that would otherwise destroy my performance that I don’t understand/appreciate just yet.

So now it is over to you, my new forum friends. What do you think? Do you have any ideas or suggestions for which way I should go?

Thanks,
Matt

 

The LS3 does NOT need much cam to wake it up. The one you mention (LS3 Stage 2) will have -11 degrees overlap, and will have a SLIGHT or noticeable lope, but will have good manners.
One up from that is their Stage 3 (220/230, .553 or .596 lift, 117LSA +4) that will still have decent low end and lope just a bit more with -9 degrees overlap. These are both regarded as mild cams. Keep in mind that 6.2's make torque nearly by accident, 6.0's only slightly less so.

 

I have a Miata with an LS3 in it, and it seems like I drive it a lot like you do on the street, light throttle and low rpms.

Anyway, this engine had a HotCam in it when I started, and it sounds like you wouldn't like the idle quality. I think somebody's "Stage I Truck Cam" might be just what you're looking for. Or any off the shelf cam that the manufacturer advertises as being usable with a stock converter in automatic trans cars. Most of these will have a slight negative overlap.

 

Grubinski, did you keep the same cam in the Miata, or can I assume you have changed it out since then? If you've changed it out, what did you change to and are you happy with it? Would you choose the same again or still go with something different?

I don't know a lot about cams, and I am not sure if the whole "truck" thing is just a general category name and they can be used whenever you like, if they do in fact fit the bill of what you're looking for. Jerry likes to wear trainers/runners/sneakers with his suits. I'm sure if you invite him to the white house and tell him its formal wear he is still going to where his sneakers. That's what works for him and nobody is going to tell him any different (nobody would judge him either).

From what I know truck cams are giving additional torque in the low and mid rpm end of the range and not giving much to the high rpm's. In my use, it is low and mid RPM torque that needs to be provided, even if actually it is at the expense of high RPM. If through the tuning process of a truck cam I have dropped from a possible 480 peak HP at 6000 RPM (with an automotive cam) and now I only have 450 peak HP at 5500 RPM (with my truck cam) but my HP and torque in the 1500 to 4000 range has increased proportionally to what I've lost in the 4000 to 6000 area then that sounds ideal to me. Power and torque above 4000 is never going to be a problem for this car. It is the low to mid RPM stuff where most of the driving will be done that needs the most help along.

 

p.s. Maybe something like the SUM-8719 ?

 

I made 408 with a stock clutch and 3.42 gears with ported 243 heads. Found out later my throttle body was only opening 90%.

 

With the bigger cube motors, they will suck up the SUM-8715 than even what more than what you're hearing on 5.3 and 5.7L. Yes, the tune is everything and you can play with the idle rpm to get it where you want. We'd recommend going with the big bore because it will deshroud the valves more and get the LS3 heads and their lighter weight hollow stem valves. The high lift version of our stage 2 truck cam is SUM-8720 and actually has -1 degree overlap rather than the -3 degrees the ghost cam does, but would pick up low and midrange torque. We think you're probably going to be making an unusable amount of low end torque, so that is something to consider. Not much use if you can't put your foot in it all the way. We also think the SUM-8719 .550 lift version of the Stage 1 truck cam would be great if you wanted a nearly imperceptible idle with strong gains (-10 overlap).

 

I put an ASA cam in it, which is what comes with the LS376/525 motor. I do not like this cam... it doesn't like running at light throttle, which is what you're doing 99% of the time with a light car / big engine on the street. It surges a bit at low rpm and creeping in parking lots, and in mixed driving it gets around 14-15 mpg, it got 18 with the HotCam. This winter the engine is getting a major going over. It will get better heads, more compression, and a *much* milder cam. From 10 degrees of overlap down to 1.5 degrees. I hope to greatly improve the mileage and driveability. If the new cam doesn't idle well enough, I will put in a new cam with even less overlap ... but I think this one will probably be good. If I get my usual driving around mileage to 20 mpg, that is sufficient. It'll probably get 30 or close to it on the highway.

The comment was made above by 'Summitracing' that you can't use tons of low end torque in a light car. That is the truth. I am going to be working on traction control for the Miata. As it stands, I can't apply full throttle until 3rd gear, and even then if the pavement or tires are cold, I have traction issues. It's a fun problem, but it's not optimal for performance. The Miata is 2400#, and the engine currently makes 462rwhp/425rwtq. Too much is never enough.

 

If you want good street behavior at light throttle, you want NEGATIVE overlap when measured at .050 lift.