what’s everyone running cam wise and intake wise? i’ve got a 6.0 that’ll have 706 heads that’ll be decked, want something that’s got a nice chop at idle but will also perform. i know not to select a cam off of sound so i can sacrafise that. i’ll be pulling a few trailers throughout the year (maybe 1-5 times)

but mostly daily driving/road tripping so don’t want it to be a top end only cam, 4l80e and 3:73 gearsPFA of what it’s going in

 

Because of towing, you can’t go big stall converter, so your limited on cam choices. Keeping the camshaft duration lower will keep torque lower in powerband, which is what you want especially with a heavy truck like this. I’d throw a low 220’s intake duration cam at it and a fast intake. Any performance (aftermarket) cam will chop some. Don’t skimp with tuning. Find a good reputable tuner and pay him whatever he wants to make it run correctly. Makes the driving experience soooo much better. Cool ride man!

 

Just throwing this out there, take a look at Summit's 8720R1 - 218/227, .600/.600, 112 + 2.
It is like a totally modernized GM Hot Cam. Some lope, very strong low and mid, good top end.
It should work with your 706 heads (good choice, BTW!) and give you a very flexible AND torquey engine.

 

Looks like a twin to mine...I'm running the same combo your going to use in my 86...

 

I want a square crew dually sooo bad. Nice looking truck, that is all.

 

There's something about a big ol' square body crew cab dually! That will definitely be a looker

Onto your camshaft quest. You've received some great advice from @Chev70elle and @G Atsma. We'll 2nd G. We like that you're going with 706 heads on this. Boosting compression will improve power and torque throughout the range. Our Pro LS Truck stage 2 high-lift SUM-8720R1 would be a great fit for this combo and goals. It may not have a window-rattling choppy idle, but it will have a noticeable lope with the idle speed turned down. More importantly, it's got the right valve events to get this dually up moving and on down the road. It has a great balance of low and mid-range power for daily or towing duties with a top-end that can carry out to 6,500+ if you're feeling sporty!

Here's an example video of the idle. This is in an un-tuned 6.0 at an idle speed of 500 RPM. ( See the 0.55-second mark for confirmation of that idle speed)

You can run the 8720R1 with a stock converter. If you wanted to get a stall converter something in the 2,200-2,500 range would work well. You'll need some better springs to pair with the cam. The Trickflow by PAC TFS-16918-16 beehives are a great match. As an upgrade, we offer the .660" lift duals TFS-250286P.

You'll need upgraded pushrods. With the 8720R1 you could end up with 7.400" or 7.425". Things vary so we always recommend verifying pushrod length before purchasing pushrods. You can do so with a pushrod length checker. We offer the Trickflow TFS-9501 pushrod length checker. When it comes to purchasing pushrods we recommend a minimum of a 5/16" Chromoly pushrod with a .080" wall thickness. You can typically find a set of 16 for around $100. From there you can get into thicker wall and or larger diameter pushrods. We offer our Pro LS HDR thick-wall pushrods. The 11/32" option with a .120" wall offers 25% less stress and 28% less deflection than a typical 5/16 x .080 wall Chromoly pushrod.

Some Cometic .040" head gaskets might be something to think about here. They will provide another little bump in compression and reduce quench. Reducing quench will help provide a more efficient combustion cycle and reduce the chance of knock. Speaking of knock. What is your estimated compression ratio and what octane fuel do you plan on running? If you don't know the compression ratio and can provide the cc's of the milled 706's we can run the numbers in our compression calculator.

On the intake. Something in the form of a FAST, Dorman LS2, or a TBSS/NNBS would work well for the combo and goals.

We went on a bit of a deep dive. We're passionate about these LS engines and our Pro LS lineup. We want to help customers build out combos, not just sell a cam and run. Let us know if we can be of any further assistance!