Jdamron17

I have the Huron v1 truck manifold t4 kit

Summitracing

Thank you for providing additional info. We have a couple of options in mind for you.

Option 1: Our Pro LS stage 2 turbo cam SUM-8706R1. Specs on it are .600/.575, 226/230, 113+4 with 2* of overlap. This is very popular for 5.3-6.0 street/strip T4 turbo builds. We wouldn't call it conservative but it's dialed back a bit from our stage 3 turbo cam. It will have a steady lope and will pull hard in the mid-range with a great top-end. It will be happy out to 7,000+ RPM with our .600" lift SUM-174004 beehives. If you're one for added insurance we offer the Trickflow TFS-2500286 .660" lift duals.

Option 2: Our Pro LS stage 3 turbo cam SUM-8716R1. Specs on it are .600/.575, 232/234, 116+5.5 with 2* of overlap. If you're up for a rowdy unmistakeable lope this would be the ticket. With its 6* at .050" IVO it will definitely have a lopey idle. However, being that this cam was designed for T4 turbo applications we dial the EVC back to -4*. This is to reduce overlap and help prevent exhaust reversion from getting back into the intake. With that being said, with its rowdy idle it won't be a bear to tune or drive on the street on your way to the strip. Your 4,000 stall converter will help tame some of that IVO and it will certainly help get everything out of the cam.

You'll be shifting the powerband to the right going with the stage 3. The IVC of the stage 3 is 46* vs. 42* for the stage 2. The IVC is basically what sets the powerband. The later we close the intake valve the further out to the right the powerband goes. The same spring packages listed for the stage 2 will work well with the stage 3.

We know our customers like combos so all Pro LS cams are offered in a variety of combos. We have cam and spring combos and cam, spring, and install kit combos.
- Available SUM-8706R1 combos
- Available SUM-8716R1 combos

You'll want some upgraded pushrods. With either of these cams, we typically see a 7.400" or 7.425" pushrod used. Things can vary so we always recommend measuring for pushrod length before purchasing pushrods. If you don't already have a pushrod length checker we offer the Trickflow TFS-9501. For pushrods, we recommend a minimum of a 5/16" Chromoly pushrod with a .080" wall. You can typically find a set of 16 for around $100. From there you can get into a thicker wall or larger diameter pushrod. For excellent stability and strength check out our 11/32" HDR pushrods with a .120" wall. These have 25% less stress and 28% less deflection than a typical 5/16" x .080" wall Chromoly pushrod.

Regarding a possible gearing change recommendation. We would need to know your rear tire diameter in inches or their P metric size (ex: 305/45-17). We'd recommend looking at this article on how tire size affects the final drive ratio. Also, we have this handy gear ratio calculator on our site.

Jdamron17

Thanks. You guys are awesome. I think I’m going to go with the stage 3. I won’t have to flycut with this cam will I? And I haven’t decided on a 26 or 28 inch tire yet. Thanks again!

Summitracing

Thank you! We think the stage 3 turbo cam will be an absolute joy with your combo. With the 8716R1 in an SBE LS1 with 317 heads, there shouldn't be a need for flycutting. Regarding gearing and tires. With 4:10 gears we would probably go with a 28" tire. Unless your converter has minimal slip then we could see going with a 26" tire.

Summitracing

Hey folks,

We wanted to let you know about our Pro LS cam GIVEAWAY we currently have running for LS1Tech members! Go check it out in our **GIVEAWAY** Summit Racing Pro LS Cam thread. Get entered in the GIVEAWAY thread for your chance to win a Pro LS cam for FREE or a gift card of equal value! We're accepting entries up until Monday, May 9th, 2022 at Midnight, Pacific Standard Time. Good luck folks

sublime1996525

iTrader: (2)

Just entered to win a cam. You guys rock! If I win I'm buying a 402 stroker kit from you as well lol.

Summitracing

Awesome! That sounds like a good plan if you win. Good luck!

FASTCRAIG

Hi. I am thinking of going with an 8714 LLTC with LS6 springs for my LY6/4l80 in a G-body with 373gears. The 6.0 has upgraded fasteners and a BTR trunnion upgrade. An LS3 intake with 92mmTB. 843 heads and engine are stock. 17/8 long tube headers with full 3" exhaust with crossover. The 4L80 has a shift kit and 3200 stall. The car will be a DD with occasional 1/8 mile trips. Does the 8714 make sense with my setup? Not caring too much about lope. I want a strong package with good manners.

Summitracing

FASTCRAIG,

Thanks for checking in on the thread asking about a cam recommendation. Our SUM-8714R1 stage 4 truck cam is a good cam. Specs on it are .550/.550, 226/230, 112+4 with 4* of overlap. We do recommend it for cars from time to time. For this combo, we'd like to see more lift and maybe a bit more duration. For a rec port application, we really like to see .600" or more lift to take advantage of that big intake valve and the rec ports.

Example idle video of the 8714R1 in a 6.0.

Similar to the 8714R1 stage 4 truck cam is our SUM-8707R1 stage 2 Automotive cam. Specs on it are .600/.600, 226/238, 113+3 with 6* of overlap. The two would idle/lope pretty similar. The intake valve opening (IVO) is basically what sets the idle quality. The earlier we open the intake the more air we take in on the downstroke (at the expense of idle vacuum). The 8714R1 has a 5* IVO BTDC vs. the 3* IVO BTDC of the 8707R1. The 8714R1 truck cam is going to have a steady lope to it just as the 8707R1 would. The added lift of the 8707R1 would improve power/torque across the range. It does move the power a bit to the right from the 8714R1 with it's 43* IVC vs. the 41* IVC of the 8714R1. You have good supporting mods such as the 3.73 gears and 3200 stall for the 8707R1. It will require a better spring than the budget-friendly LS6 springs. We recommend a .600" lift beehive such as our SUM-174004. As an upgrade you could go with the TFS-2500286P .660" lift duals from Trickflow.

Example idle video of the 8707R1 in a 6.0. The first clip is the stock cam. See second and third clips for the 8707R1.

Either of these two are going to have a steady lope to them but will tune well and be easy to live with. The 8714R1 has .550" lift going for it for the budget-frienndly LS6 springs. The 8707R1 has the added exhaust duration, .600" lift, and 2* of overlap for more power all while having similar manners to the 8714R1. You'll just need better springs.

We're going to throw out a 3rd option. It seems you may want a cam that has a smoother idle and mild manners. Take a look at our SUM-8715R1 known as the Ghost cam. Specs on it are .600/.575, 222/234, 115+3 with -2* of overlap. The Ghost cam will have a smooth idle to noticeable lope depending on idle speed. Comparing the IVO's it has a -1* IVO. It's opening the intake valve 6* later than the 8714R1 and 4* later than the 8707R1. Plus with -2* overlap it's going to idle much smoother than the other two and be mild-mannered. Don't let that fool you though the Ghost cam packs a punch and carries power out well to 6,800+ rpm. It would work with the same spring packages as the 8707R1.

Example idle video of the Ghost cam in a 5.7.

We think you would be happy with any of these three. Let us know if we can be of any further assistance. We'll be happy to help!

Kawboom

Like a loving girlfriend once said; "It's okay to have a small cam, honey, the big ones just hurt anyway..."

knappo99

iTrader: (1)

I have a completely stock 1999 ls1 and was trying to decide on a cam. I have 6.0 heads ported by tea and some home ported 799 heads . I was looking at the 8715 but the rod bolts in the engine may be questionable at extended rpm’s. Would something like the 8720 be better considering the possibility of lower compression and limited rpm? Street usage only, possibly daily driver. Also mileage is now a bigger concern with prices going up. Or should I just stay with stock and put in some higher ratio rockers as a budget upgrade ( since I already have some) small chance of turbos (I have most of the parts already) thanks

Summitracing

@knappo99,

Thanks for checking in on the thread asking for a cam recommendation.

We would go with the TEA ported 6.0 heads. Assuming these are 71cc and without milling, they would net you around 9.7:1 with a .051" head gasket. You could go to a Cometic .040" head gasket and bump that up to 10:1. This would also help reduce the quench distance which helps promote a more efficient combustion cycle and reduce the chance of knock.

Onto a cam recommendation. The SUM-8715R1 "Ghost" cam is very popular for LS1 builds. It will have a smooth to noticeable idle depending on idle speed. With -2* of overlap, it tunes well and is easy to get along with for a daily driver. It packs a punch and makes good power out to 6,800+. The Ghost cam works well with a .600" lift beehive springs or as an upgrade you can go with .660" lift duals. While we recommend a 2,500+ converter it will work just fine with the stock converter.

If you're looking for more low-range and mid-range performance the SUM-8720R1 stage 2 high-lift truck cam is a good one to look at. It will have a noticeable lope depending on idle speed. We have plenty of folks that use this in cars for the exact reasons you're looking for. It makes good power over the stock cam, it will be easy to get along with and maintain efficiency. You can use either of the same spring packs that we mentioned above. It will work just fine with a stock converter.

Don't forget about our cam combos to make the cam swap easier. We have cam and spring combos or cam, spring, and install kit combos.
- SUM-8715R1 combos
- SUM-8720R1 combos

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

wannafbody

iTrader: (2)

Wouldn't the stage 2 turbo cam work better with 2 degrees overlap as a NA cam than the stage 2 street cam with the extra 4 degrees of overlap?

Summitracing

@wannafbody,

This is one of those "It depends" answers. Are we talking about a mostly stock combo with a full stock exhaust system or are we talking about something with bigger cubes and a free-flowing open exhaust system? Does the customer have the gears and or converter to help tame some of that overlap? Then we have to factor in the customer's wants and needs. Some customers don't mind a bit of character while others want near OE driveability. This is just a bit of info we try and cover when making a cam recommendation.

In general, the SUM-8706R1 is in the "Single T4 turbo cam" category due to that low overlap of 2*. We limit overlap in the T4 single cams by closing the exhaust valve early. If you look at the single T4 turbo cams chart on our site you'll see those cams close the exhaust valve at 0* ATDC or mostly BTDC. We do this due to the restrictive nature of the T4 to help prevent/reduce exhaust reversion from getting back into the intake. From time to time we'll offer up the 8706R1 as a recommendation for a NA car or truck. It all depends on the combo and goals. We place cams in categories to help the novice customer narrow down the right cam for them. As you can see in the Single T4 cam chart we pulled over a couple of truck cams (SUM-8728R1 and SUM-8720R1). That's an example that cams fit into different buckets/categories.

Thanks for raising this question wannafbody it's a good one.

For anyone that wants to read up on cam selection, cam specs, and individual timing events check out the two-part article below.
Part 1 - Comparing Camshafts: A History of Camshaft Specs and Choosing the Right Cam
Part 2 - Comparing Camshafts (Part 2): Consider Individual Timing Events When Choosing a Cam

We're not here to just sell parts. Obviously, that's part of it being that we're a retailer. However, we want to help make more knowledgeable buyers and engage with the community

grubinski

I have to say, I enjoy this thread a bunch. Nothing is as fun as bench racing camshafts. :-)

The LS3 in my Miata will be out next winter for a valve spring swap (preventative maintenance due to "high" lift) and some other routine maintenance. I am pretty happy with the current cam in the car (227/232 .646"/.650" 114+1 to go with 11.8:1 CR), which makes 471rwhp/425rwtq. However, I might want to tame it down a teensy bit in the idle / low speed area. The car is street driven 99% of the time, road tripped whenever I can, and has a very light flywheel (25# flywheel and clutch total) in addition to only weighing 2400#. Any bad manners at light load low rpm is reflected in some bucking and surging. I've tamed it a lot in the tune, but had to pull a bunch of timing to do so.

I'm thinking something like 226/230 116+2 ... 47 IVC (need that to run 92 octane), -1 IVO, 53 EVO, -3 EVC, so -4 degrees of overlap instead of +1.5 degrees, and a bit earlier EVO.

My understanding is that this will definitely improve idle quality, reduce low rpm torque a bit (and perhaps the peak torque), and maybe spread the torque curve out a bit flatter. With IVC of 47 degrees, it should still pull just as hard up top, perhaps marginally better due to the slightly earlier EVO.

My question is, how far up the rev range does the "idle quality" improvement go? Will it be smoother at 1400 rpm? 1800 rpm? With the current gearing, I spend a lot of time at 12-1800 rpm at light throttle. If the lower overlap cam would run better there in addition to at idle, it'd certainly be a compelling argument to try it out. If the lower overlap would improve cruise fuel economy at ~1600 rpm, that would be a plus.

Kawboom

That is a very, very small change in cam.

grubinski

Agreed, but it takes overlap down by 5.5 degrees, which *is* significant, IMHO.

G Atsma

Small cumulative changes CAN make big differences.

Kawboom

Sometimes. In others, you would never notice the change, except for the missing money.

G Atsma

If he who makes the changes knows what he is doing, the differences WILL be felt.