"Tow Pig" build

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My guess is to keep compression at a manageable level, (317's have large chambers) but I will let Cline speak for himself.

Most likely, but compression could also have been handled with piston selection since he is replacing them too. That's why I hope he chimes in. It clearly was planned out and not cobbled together. I'm not familiar with all of the intricacies of Gen III/IV builds, so any info I can gain will only make me better.
 
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I am interested to see how well this works, I would have thought something like a Brian Tooley Racing Torque cam would have been more appropriate for towing, but the cam used does have a pretty wide LSA at 116 and almost 40 more ci than the 6.0.
 

clinebarger

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Sir, that is some beautiful work there. One question: Why did you decide to go with the 317 heads? I ask because I am planning an LQ4 build for my old Nova, and am looking at using the old 823 heads off of my Denali that I swapped out last year.

If this was a high performance/RPM build......I would have used L92/LS3 heads for the larger Intake Ports & Intake Valves. 823 castings usually have a 68-70cc Chambers & 317 castings are 70cc-71.5cc so there's not much difference in chamber volume between the two.

The Cathedral Port castings are optimum for low RPM torque production & the 317 Chamber size allowed me to use an off the shelf piston & still have a reasonable compression ratio for the duty cycle & almost the ideal Quench Clearance of .048" (Ideal is @ .045").

Numbers are as follows...
Bore Diameter 4.005"
Stroke 4.000"
Gasket Bore 4.020"
Gasket Thickness .051"
Chamber Volume 70cc (Actual after surfacing)
Piston Dish -12cc
Piston height +.003"
**Comes out to.....9.98:1 compression ratio



If you were to use the stock -6.7cc Dished LQ4 pistons & 823 castings.....
Bore Diameter 4.003"
Stroke 3.64"
Gasket Bore 4.020"
Gasket Thickness .051"
Chamber Volume 68cc
Piston Dish -6.7cc
Piston height +.006"
**Comes out [email protected] 9.93:1 compression ratio
If you were to use LQ9 flat top pistons or a flat top with the same piston height.....You'd have @ 10.7:1 CR which be more ideal for a performance engine running premium fuel (And a good tune)
 
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If this was a high performance/RPM build......I would have used L92/LS3 heads for the larger Intake Ports & Intake Valves. 823 castings usually have a 68-70cc Chambers & 317 castings are 70cc-71.5cc so there's not much difference in chamber volume between the two.

The Cathedral Port castings are optimum for low RPM torque production & the 317 Chamber size allowed me to use an off the shelf piston & still have a reasonable compression ratio for the duty cycle & almost almost the ideal Quench Clearance of .048" (Ideal is @ .045").

Numbers are as follows...
Bore Diameter 4.005"
Stroke 4.000"
Gasket Bore 4.020"
Gasket Thickness .051"
Chamber Volume 70cc (Actual after surfacing)
Piston Dish -12cc
Piston height +.003"
**Comes out to.....9.98:1 compression ratio



If you were to use the stock -6.7cc Dished LQ4 pistons & 823 castings.....
Bore Diameter 4.003"
Stroke 3.64"
Gasket Bore 4.020"
Gasket Thickness .051"
Chamber Volume 68cc
Piston Dish -6.7cc
Piston height +.006"
**Comes out [email protected] 9.93:1 compression ratio
If you were to use LQ9 flat top pistons or a flat top with the same piston height.....You'd have @ 10.7:1 CR which be more ideal for a performance engine running premium fuel (And a good tune)

Thank you for the detailed explanation. I'll be looking for at least 6000 RPM out of my build because the governor in my 2004R shifts around 5500 at WOT. The stock LQ4 bottom end specs are where I will be. My Denali still likes to pull 5-6 degrees with knock retard on 91 octane, so around 10:1 is probably where I want to be in the Nova.

I'm looking forward to seeing your build at completion. It's gonna be nice.
 

clinebarger

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Timing set installed.....

*Some of you guys might notice I'm using a 4X Gen IV Cam Gear, The original Gen III gear was discontinued & superseded to the 1x Gen IV gear which is twice as much.....The 4X gear works fine on Gen III engines!
*Pre-stretched, Seamless Roller IWIS chain sold by Hinson Motorsports & called C7-R Timing Chain.

Oil Pump.....Just a OE LS6 pump.


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Did you torque the head bolts with a Techangle torque wrench, or did you use an actual torque angle gauge? I ask because I used ARP bolts on my 6.2 and torqued to ARP's spec. I just put a cam and lifters in a 5.3 for a friend after one of the AFM lifters rotated 90* in the tray and wiped out the cam. I put OEM TTY bolts in that one, and noticed 8-10 foot pound variations from bolt to bolt with my Techangle. It was just more variation than I expected.
 
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clinebarger

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I use a 1/2" drive Snap-on Techangle torque wrench.

I only see a few foot pound variation, But take a few precautions that I've learned over the years......
*Lube under the Head of each bolt with ARP Ultra Torque.
*During the Initial Torque sequence (22 Ft Lbs), Run several passes per head......Slowly pull on the wrench & you'll notice that some of the bolts didn't actually reach 22 ft lbs because the gasket doesn't just automatically compress evenly.

There's enough leeway in the design that it's not super critical & what you observed is quite common. I mark the heads out of ingrained habit.....The Techangle counts the bolts for you.
 

ls1mike

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No reason to run ARP head bolts or studs, LSx engines don't have head gasket issues.
I did it on the Caprice, but the WS6 is running the OEM ones. Figured I was in there. I think I used the same head gaskets.
I have not seen those lifters before. I am interested in what you think of them.
I need to stay out of this thread as the I can hear the truck out there asking for a cam. :)
 

ls1mike

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I get it! ARP's are easier to torque in the vehicle as well. I'm sure you would agree....This build doesn't call for ARP head bolts.
Nope I agree, these came in the kit I bought so I figured why not. I used BTR LS7 lifters. I couldn't find the GM ones at the time. Are the ones you are using a pretty new item?
 

clinebarger

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Fairly new product, Though this engine won't strain them much RPM wise.....I'll report back with any failures.

LS7 lifters have always done well for me in the past, Especially since I started using Cam Motion grinds/profiles.
 
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Oddly fascinated with this project - any updates?

How does one match parts together for something like this? (Lifters, heads, even gaskets, etc). I'm guessing the harness / brain box is a nightmare.

I get that there is a lot of skill involved - but is there a community of engine builders who share what works with what? (Genuine question from someone who can barely figure out a stock engine).
 

ls1mike

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Oddly fascinated with this project - any updates?

How does one match parts together for something like this? (Lifters, heads, even gaskets, etc). I'm guessing the harness / brain box is a nightmare.

I get that there is a lot of skill involved - but is there a community of engine builders who share what works with what? (Genuine question from someone who can barely figure out a stock engine).
I am sure Clinebarger will answer you. Cline is really experienced and probably does all that on his own. For me when I do my head/cam swaps on LSx stuff I will talk to people with similar setups. There are so many groups and people who have done LSx swaps/upgrades you can bet someone has done it before and is willing to help you out.
 
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