Summitracing

Thanks for checking in on the thread for a cam recommendation. We can see a couple of cam options for you.

Being a stock 5.3, LS6 manifold, and stock throttle body we'd look at the Ghost cam. That's part number SUM-8715R1. Specs on it are .600/.575, 222/234, 115+3 with -2* of overlap. It's stealthy and smooth but packs a punch when you lay into it. It will ring out to 6,800+ with the ever-popular PAC 1218's which we carry through Trickflow asTFS-16918-16.

With better-supporting mods such as an aftermarket intake and throttle body, we could see the stage 2 working. That's part number SUM-8707R1. Specs on it are .600/.600, 226/238, 113+3 with 6* of overlap. The stage 2 will have a steady lope but it's easy to tune and live with. It has a wide powerband and pulls strong to 7,000+ RPM with 150 lbs. seat pressure.

Regarding cylinder heads. We could see a couple of options here as well. You could have the factory 706/862 heads worked over by someone like Total Engine Airflow. Have them mill the heads, do a bowl blend, and maybe even have them install a larger 2" intake valve. Depending on your budget you could go aftermarket. An option could be a Trickflow Gen X 205cc CNC'd TFS-30510001-C00. These have a 58cc chamber and would bump compression to just under 10:1 with stock .051" head gaskets. With a .040" head gasket you could bump that up to just under 10.2:1.

We're here to help. Let us know if we can be of any further assistance.

Summitracing

Thank you @68Formula . You're on point and leading @5.3TURTLE in the right direction.

5.3TURTLE,

The 8707R1 would be on the too big side for this combo and goals. The 8715R1 "Ghost" cam and 8720R1 (Truck stage 2 high-lift) are the ones we'd look at here. We would favor the 8720R1 as well. With its 39* IVC it will get you up out of the corners. At the same time it has a wide powerband out to 6,500+ so you should experience less up/down shifting time. This gives you more time to get up on the wheel and hit your marks

Let us know if we can be of any further assistance. We'll be happy to help!

5.3TURTLE

Thanks Summit and 68!

CatfishC5

Hey Summit, Looking for a cam sugestion on a LS1 with long tubes, CAI, LS6 intake 4l60e with stock converter, 3.15 rear gear. Will run a stall if needed but gear has to stay. Im mainly interseted in the drag and drive events and index/bracket 1/4 mile. Will be going with a set of ported heads from Advanced Inductions (243 or 706). Not trying to set the world on fire, 11.5-12.0 ET is the goal. How much low end will the gost cam give up compared to the truck cams, is the gain in the low end worth the loss on the top end for my goals. Thank you.

slowpoke96z28

iTrader: (2)

I can see going to a bigger manifold, but I wanna keep the tb since I have that TNT power ring on it, so I figured a bigger manifold would be pointless. I don't mind going bigger on the manifold if it will still help. I see the LM7 has a 8cc dish. I guess that means relying on compression ratio for engine output is a nogo without messing with the shortblock?
Can you project an ET for those combos?? Trying to be the quickest daily driven stock bottom end lm7 there at the track, so I gotta know how much barking I can back up lol.

G Atsma

Thinner head gaskets are an option, where you can also improve the quench.

68Formula

Assume you're comparing the Ghost Cam to the Summit Truck Stage 2 High Lift (.600" lift will take advantage of the ported heads). Both cams should be capable of meeting your goals (with good traction). The 3:15 rear gears will hold you back some, but at least the Vette is light, your running long tubes, and presumably bumping up the compression ratio with the heads. Plus sounds like more of a strip car than daily driver and cruiser. If you can add a stall and higher compression, go with the Ghost Cam so those heads can eat.

CatfishC5

Thank you for the reply, the car has been 12.5s this summer and hoping for a little better times this fall in better air, I was hoping I could make up for the rear gear with some tq down low, yes Im hoping for 11.5 or so compression. I think the ghost cam would work just dont want to give up a ton of low end.

Summitracing

Thanks for letting us know about the Oldie but goodie TNT Power Ring. Since you're spraying and want to keep that setup we'd stick with the stock manifold. With that being said we'd go with the Ghost cam. If you're truly going to be trying to daily this we wouldn't recommend the 8707R1 in a stockish LM7.

Yes, the LM7's have an 8cc dish piston. Depending on end goals you could go a few different routes.
- You could leave it as is and just hit it with the spray.
- Put some .040" head gaskets in for a little bump to 9.8:1.
- Throw some 4.8 0cc flat tops in it for a good bump in compression. With stock .051" head gaskets and the factory 706/862 61cc heads, you'd be right around 10.5:1.
- You could jump up to a forged piston if you wanted. We have our forged 2618 Pro LS pistons. To boost compression in a stock bore 5.3 we offer the SUM-326945780-2P -2cc dome piston. This is for the .945" gen 3 press-fit rod. That piston would boost compression to 10.9:1 with the stock heads and stock. 051" head gaskets.

This gives you some options to think about whether you want to stay SBE or get into the short block and or heads.

Summitracing

@68Formula your assessment is spot on here.

Regarding the truck cams to the automotive cams. In general, truck cams are designed for well big heavy trucks. They need an early intake valve closing (IVC) to get up and moving and to keep torque efficiency for towing. In a light car such as a C5 Vette, we don't really need to worry about that.

We'd go with the Ghost cam and ported 243's. We'd also mill .020" or so off the 243's for a compression bump. To add another compression bump go with .040" Cometic head gaskets for an added bonus of reduced quench. Boosting compression improves power and torque throughout the range. Go with a 2,500+ RPM converter and you'll be ready to go out and accomplish your goals. At the same time, you'll be able to go cruising with ease in the C5 with the Ghost cam.

CatfishC5

Just bought a set of Advanced Induction 226cc 799s 65cc with BTR .660 duals and titanium retainers, is this to much spring for the gost cam? About to call summit and get the cam just want to get the right springs as well. I already have a set of .048 MLS gaskets, should I take the heads to 62cc and run those gaskets or get a set of .040. Thank you for your reply.

Summitracing

Those springs will work well with the Ghost cam.

Regarding the heads and head gaskets. You'd be right around 10.6:1 with the 65cc heads and the .048" head gaskets. If you cut the heads to 62cc with the same gaskets you'd be up to 11:1. Add in the .040" head gaskets and you'd bump it up to near 11.3:1 right near your 11.5:1 target. From what we've seen right around 11.5:1 is about the limit for 93 Octane in cars. You might find that your tuner will need to pull a bit of timing to keep the engine out of knock. For future reference, we have our own handy compression calculator right on the site.

Dadillac21

Summit I tried to PM you but it wouldn’t let me as I’m too new . I have been impressed with your attentiveness on the board and am interested in your cam/component suggestion for my cts-v. It is an 05 ls6 car and currently has LTs and full exhaust , CAI , tuned and shortly stage 2 creative steel motor mounts . I plan to have the 243 heads ported and polished by a very well respected local business . I cannot for the life of me decide on a cam and springs or trunnion . I want all the power I can get while still having decent street manners and it may be silly but I want a nasty idle that turns heads lol I’ve been given very generic cam suggestions so far from well known businesses . What would you suggest ?

Summitracing

Thank you for checking in for a cam recommendation. We enjoy being a part of the community and interacting with fellow members! We understand wanting a nasty window-rattling idle. Although sound is subjective a "nasty" idle typically comes with poor street manners. Think of an old-school hot-rod shaking and lunging at a street light. That looks cool and sounds "nasty" but it's a bear to keep it idling and isn't pleasant for daily use. For decent street manners you may have to give up that nasty idle for a steady lope. There’s a few cams we’re thinking of.

The first option we'd look at is our own Pro LS Automotive stage 2 SUM-8707R1. Specs on it are .600/.600, 226/238, 113+3 with 6* of overlap. It might not have that nasty unsteady lope you're after but it'll have a strong steady lope with its 3* IVO. The nice thing is it won't be a bear to tune and it'll be easy to live. It has a nice wide powerband that will work well with your combo and planned head work. You can pair it with PAC 1218 beehives which we carry through Trickflow as TFS-16918-16. If you're one for added insurance we offer .660" lift dual springs TFS-2500286P. When going to dual springs we typicaly recommend going with a trunnion upgrade. We offer both a bearing and bushing option within our own brand.

See an example idle video below. You can always have a tuner play with the idle speed and timing tables to get more lope out of a cam.


The second option we're thinking of is the Cam Motion Hotrod LS cam. That's part number CXM-03-01-0075 with specs of .595/.587, 227/237, 111+4 with 10* of overlap. This will get you that unsteady lopey idle with its 6* intake valve opening. It wouldn't be as well-mannered as our 8707R1 but it would still be manageable with a good tune. This cam would work with the same spring packages as our 8707R1. It has a pretty early intake valve closing of 40.5* compared to our 43* IVC of the 8707R1. That means the Cam Motion cam would be better on the low-end but it would peak sooner.

We did some digging but couldn't come up with an idle video of the Cam Motion Hotrod LS cam. There could be one out there we just haven't found it yet.


There's one more option we will put into the ring. That's our Pro LS Auto stage 3 "Extra clearance" SUM-8710R1. Specs on it are .625/.605, 230/242, 113+3 with 10* of overlap. It draws the IVO back a degree to aid in PTV clearance for rectangle port heads. We like the valve events of it and it's a viable option for your combo and goals. It has 5* IVO so its idle would be in between that of the 8707R1 and the Cam Motion cam. This would have the highest powerband of the three. It's geared more towards mid-range and top-end power. This cam would really take advantage of your planned head work with its added lift and largest duration of the 3 cams. This would require the TFS-2500286P .660" lift dual springs.

Here's an example idle video of the 8710R1.

This gives you a few options to look over. We're here to help so look these over and feel free to let us know if we can be of any further assistance!

CatfishC5

After reading Mavn's build thread and seeing that the Gost cam made power to 6500-6700rpm would advancing the cam a few degrees lower the peak to around 6200rpm and help with bottom end a little? Is there any downside to advancing it more?

68Formula

If it peaks too high for you, just run the 8720R1. The difference between the two in intake closing point is 4 degrees. If you were to advance the Ghost cam to match to bring the rpm down, the couple extra degrees of duration is not going to be significant within your target rpm range. Your total area under the curve for power in 2nd and 3rd gear will be similar, and you'll have more torque out of the hole in 1st. And then you can keep the compression where it is (still run the thinner gaskets Summit suggested though for better quench), and stock convertor. That will still meet your original goals.

Summitracing

@68Formula is spot on again. You can advance the Ghost cam a few degrees to bring in the powerband sooner. However, we wouldn't recommend advancing a larger cam to work in the lower RPM range you're shooting for. If you're looking for a lower peak the stage 2 high-lift truck cam SUM-8720R1 that 68Formula recommended is a great fit for your combo and goals. It will work with the same .660" lift dual springs you already have.

G Atsma

Interesting. To myself, I have referred to the 8720R1 as the "optimized GM Hot Cam" only due to the similarity in duration and LSA. I would bet that with the increased lift and more modern lobe profiles, it outdoes the old Hot Cam by a decent margin. Are there any dyno tests out there that compare the two? I always thought that the one thing that held the old cam back was the .525 lift, especially in something around 6.0-6.2 liters. Plus the old profiles.

Summitracing

G,

You have a good eye for spotting things. Yes, the 8720R1 and the GM Hot Cam share the same duration at .050" and LSA. However, that's about where the similarities end. The .600" lift is a part of where the similarities end. A lot of it has to do with our shorter seat timing. Then the design of our Pro LS lobes that provide vastly improved valvetrain stability. Unfortunately, we don't have dyno results comparing the two. That would certainly be something we'd like to do in the future.

G Atsma

Thank you so much for the great response! If used on an otherwise stock 6.0-6.2, (because ALL those engines ever need is a cam...) would you hazard a guess at how much better your cam would do vs. the old, grizzled, Hot Cam?