Hello, I am swapping an LQ9 into my 2005 Silverado 1500 4x4. The drivetrain is stock but I don’t mind doing some transmission or converter work, this is my daily driver so gas mileage and driveability are very important. The motor has a stock bottom end with a FAST lsxrt intake, 102mm TB, larger injectors, trick flow aftermarket heads, and long tube headers. I want a good truck cam that has a slightly lopey idle and can maintain fair enough mpg and driveability for a daily. Whatever cam can produce the most power while retaining those characteristics is for me, and I am open to suggestions entirely. I have narrowed down to three cams and was wondering what your guys thoughts might be on each. Thanks!

https://www.summitracing.com/parts/sum-8713
https://www.jegs.com/i/COMP-Cams/249...6L+%2F+364+%29
https://www.jegs.com/i/Crane-Cams/271/1449121/10002/-1

 

sum-8720

 

just curious, what makes you say that one? Thanks

 

It's a very flexible cam with plenty of lift. It is essentially a copy of the GM Hot Cam with a bunch more lift at a bargain price.

 

Those are 3 VERY DIFFERENT cams. Not sure why you picked those particular ones. The result from any of them would be RADICALLY DIFFERENT from any of the others.

The one thing you DO NOT WANT in a truck is "lope". That will cost you what you need the most, which is, TORQUE. It's not much fun sitting at a stop light with some hoaty-groaty sounding motor, and watching somebody with a STOCK, or at least stock-sounding, motor pulling away from you. (having humiliated quite a few people that way over the years)

I'd suggest something like the TPS "STAGE 3 truck cam". it's something like 216/220, not sure the lift. 3000-ish converter. Get it from Edge or Circle D or somebody like that, NOT B&M or somebody like that.

 

I spoke with 3 different techs with experience in LS Cams and each one gave me those and looking at them I saw they were totally different. I gave them the same info I said above, that’s where those 3 came from. And seeing as how dissimilar they were I needed some help
choosing the right one. And I see where your coming with the lope, I never got anted much of a lope anyway just a little bit to give it a more aggressive sounds profile. But you would go with a TSP over like a BTR or a Crane? Also one more question I saw that one specd out for a 5.3, you think it would still produce good results in the 6.0? Thankyou for your help

 

Its been tested and makes GREAT power across the curve.
I HAVENT RAN IT but if I was putting a cam in a truck, thats the one I would be picking due to the dynos I have seen comparing it to other cams and its price is great too.

check youtube there are a few videos of it having a slight lope with a fairly open exhaust.

 

Scroll that video to 17:35 to see a comparison with that cam and a couple others more aggressive cams.

Even the smaller 8720 will loose power below 3300 or so but I think on a 6.0 it wouldn't be as drastic as the engine in that video is a 4.8.

 

Texas speed stage 3 or 4 5.3 high lift truck cam. And a circle D 2800-3000 stall. Not that you necessarily need the stall, but you WANT the stall.

Either of those cams is about as much as you can go before needing a stall but 4L60's have really tight converters and giving it a little more stall will drastically change how quick the truck is.

And if you had to choose between stall and cam, do the stall. Unless you're towing quite a bit then we need to look at this a little different.

 

I like that he uses the little 4.8 quite often, as it is the "worst case scenario", in that with any other engine, it can only get better, low-end power-wise.

On a side note, remember that any power numbers from a Holdener test, or any dyno comparo for that matter, should only ever be compared to others from the same dyno session.
This is true for any dyno test, as there are too many variables between dynos, weather conditions, which (or any) accessories on the engine, etc.

 

I have used it to tow before but not often so that isn’t a priority. Right now I’m deciding between the stage 3 HL and stage 4. But I will definitely be getting a stall to go with it

 

Under camming is better than over camming if that helps you choose.

Call texas speed and discuss this with them and see if they can help you choose

 

Before you spend that much money on a converter I would be saving for a 4L80

 

Here's the deal:

Dyno numbers are GREAT if you're looking for "max power". Cams that deliver "max power" have to do that by moving the engine's operating RPM range up higher, at the expense of torque at low RPMs.

A "max power" cam works GREAT in a light car with LOTS of gear. That combination allows an engine equipped with a "max power" cam to hit its optimum RPM range quickly, while putting only a very light load on it when it's inefficient.

Put this in perspective: you DON'T HAVE a "light car". Instead, you have almost as much weight to move around as TWO WHOLE LIGHT CARS (something in the 5500 lb range) with a gear that's roughly equivalent, due to tire size, to a 3.08 or AT BEST a 3.23 gear in a car with the smaller tires that a car has. Picture that in your mind: a car with a TERRIBLE gear to begin with, with A WHOLE ADDITIONAL CAR stacked on top of it; and you're going to try to make ALL THAT "fast" somehow. That's the challenge you face. A cam recommendation that works for a car will fall FLAT ON ITS FACE in the pile of machinery that those of us with 4WD trucks are dealing with.

The first thing you gotta do is, GET IT MOVING in the first place. Doesn't matter how bad-*** it is from 80 mph up in 2nd gear, if it takes you 35 seconds to get there. Which is EXACTLY what will happen if you pick a big cam.

The right cam for you is this one https://www.texas-speed.com/p-8558-t...-camshaft.aspx with ALL of the supporting hardware, PARTICULARLY, valve springs. Ask TSP what they recommend for those, and whatever the higher / optional recommendation is - NOT the "least you can maybe get by with" - FOLLOW IT.

 

^^^^^^^^^ This man speak truth, Kemosabe....

 

That sounds perfect, the TSP stage 3 HL With probably 112 LSA was the one I was looking at getting. And I definitely will not cheap out on valve springs and a converter. Getting good springs rated to .600 with pro magnum roller rockers and like a 3000 stall. It’s a z71 so not sure what gears it has but I totally get what you are saying. I’m fairly new to this stuff but am trying to get as informed as possible and am fairly well versed in the basics by now. Thankyou very much

 

Not sure I agree with a lot in this thread. If he was building a cam, headers stall GMT-800 6.0 truck I'd say yeah be careful and don't put in to much camshaft. This build is far from that with the FAST 102, Trickflow heads, injectors, longtubes etc. This is a potential 450+ whp build that needs a cam that doesn't fall off before the heads and intake are beginning to pay dividends for their large price tag.

Why limit the RPM range to 6000 with a small camshaft when the heads/intake were designed for power throughout the curve to 7000+ RPM? My GMT-800 with a stock bottom end LQ9, PRC 225 heads, with less intake/tb (TBSS/92mm), 231/234 629"/615" 111 LSA, 3200 Circle-D, 4.10 gears has plenty of bottom end power, enough to to rip the tires off through 1st, 2nd and into 3rd, and wants to keep pulling past my 7000 limiter. The LQ9 has the good rods, shouldn't be afraid of a thousand more R's IMO

 

Z71 doesn't tell you anything about gears, or anything else mechanical. It's skid plates, upgraded shocks, presence or size of sway bars in some years & models (I don't think that detail applies to yours), and STICKERZZZZ!!!! but nothing mechanical. That said though, a typical vehicle equipped with it usually is otherwise pretty much optioned-up, including the sportier powertrain choices. They don't put that package on fleet work trucks, only on ones that are toward the top of the price range.

Most common gear in a truck like yours is 3.73. That's what my 04 Avalanche (w/ Z71 FWIW) has, and more than likely that's what you have too. RPO code GT4 on the SPID label. My Av weighs about 5850, a pickup of course will weigh somewhat less.

I worked the gearing situation out BTW: my truck has the stock 17" tire size on it, 275/70 if memory serves; but I measured it at 15" from center to the ground. Compared to a typical car with 26½" diameter tires (13¼" from center to ground), which is about what a Vette or F-body has, that works out to the same drive shaft speed as 3.29 gears in such a car. If your truck has bigger tires than stock it could be worse. You could benefit from ALOT more gear but your gas mileage might be affected.

While the better heads and intake and all that will help the higher RPM horsepower, they won't do squat for bottom end, which is where a DD truck spends its life. Speaking strictly for myself, outside of the occasional blast up a freeway ramp or something, mine doesn't see above 4000 RPM more than a couple of times a month, and most of the time it's below 2500, especially cruising. For a DD, that's pretty much what needs to be optimized; not 7000 RPM. Even though the motor might be perfectly capable of it. The vehicle simply doesn't provide much opportunity to use that. Great to have on those rare occasions, but the other 99.9% of the time, 2000 - 2500 RPM is where it needs to be useful.

What mileage does it get now? Is that with the stock 5.3? (fyi, mine gets just about 14 mpg, with totally stock 5.3 except LT headers and a tune) What are you willing to tolerate? A little bit of gear might not hurt it too much, might even help, but ALOT more (4.56 or more) would probably hurt it. Plus it would be kind of expensive, having to do both front and rear.

 

What compression and which TFS heads?

 

The Trick Flow GEN X 515 HP Kit with the 215 heads comes with the equivalent of the Sloppy Stage 2 camshaft 228/230 which is a good matching kit. With the Fast 102 a little more camshaft is not unreasonable. If you spend the big bucks on Trickflow heads and a Fast 102 you're dropping at least $3,500. If he wanted to limit horsepower and torque why even purchase these super nice hotrod parts? So you're saying these parts are worthless for bottom end torque? We all need 706 heads with tiny 1.89/1.55 valves, a 212/218 camshaft, stock LS1 intake with a 78mm throttle body to produce HUGE torque numbers?

With respect... I don't understand that mind set. When you already have two very nice pieces of bolt on go fast goodies... why put on a governor? When a warmed over stock head, mild cam build runs out of that "instant bottom end torque" the aftermarket heads, cam, intake build is going to say bye bye. Again with respect... this is a potential 450 whp build and if he limits his fun to a 4000, 5000 or even 6000 RPM blasts up the freeway ramp... he's not having fun yet