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Advice on Engine Build

igotzzoom

SM 2017
SM 2016
Full Member
Joined
May 30, 2016
Messages
90
Location
Orange County, CA
Hi Guys, I'm itching to get more power in my '04 Z71. Here are the different scenarios I'm considering. I'd love to hear your experiences doing any of them, or something different. The key issue is I live in California, and I want to be able to smog it without a headache.

1) Bore existing LM7 iron block to LS1 (3.898 in) spec, new pistons, LS6 heads, LS9-grind cam, Magnacharger TVS1900 Radix blower.

2) LQ4 or LQ9 long block, Maggie blower, shut the hood & call it a day

3) LQ4 or LQ9 short block, AFR CARB-legal heads, LS9 cam), Maggie blower

4) Gen IV LS3, Maggie blower

5) LSA Crate engine (If I can pull together enough money)

I know I'm going to have to beef up the 4L60 for it, but if I'm having the engine built outside the truck, might as well get a built 4L60, and put them in together.

Thanks in advance for your feedback and experiences.  
 
beef up rear end too...
 
I would think 5 would be about the same cost as 4 (possibly even cheaper), unless you can find a used LS3.

The LS9 camshaft is really designed for rectangular port heads (hence, can get away with less intake duration).  It also has a crazy wide lobe separation.  A better choice would probably be a Lingenfelter Camshafts L210065297.  You can compare them below:
https://www.summitracing.com/parts/lpe-l210065297/overview/make/chevrolet
https://www.summitracing.com/parts/nal-12638427

I'd say if rebuilding the LM7 to 5.7L, use the Lingenfelter camshaft, have the stock heads rebuilt and ported by Total Engine Airlfow, and the exhaust valve faces ceramic coated for extra detonation insurance.  Make sure the pistons you pick keep the compression ratio under 10:1 for use with the blower. Build the hell out of that 4L60E, and remind your tuner, that's what your running.  If you have the G80 rearend, swap in a Trutrac differential, and (assuming stock tire height) put in some 3.73s while you're in there.  Use a stronger cast cover, such as this  http://www.bmracing.com/products/70502-cast-aluminum-differential-cover-for-gm-82-85-86/.


You might be better off though finding a LQ4/4L80E combo and swapping both together.
 
Bigtrucklover said:
I would think 5 would be about the same cost as 4 (possibly even cheaper), unless you can find a used LS3.

The LS9 camshaft is really designed for rectangular port heads (hence, can get away with less intake duration).  It also has a crazy wide lobe separation.  A better choice would probably be a Lingenfelter Camshafts L210065297.  You can compare them below:
https://www.summitracing.com/parts/lpe-l210065297/overview/make/chevrolet
https://www.summitracing.com/parts/nal-12638427

I'd say if rebuilding the LM7 to 5.7L, use the Lingenfelter camshaft, have the stock heads rebuilt and ported by Total Engine Airlfow, and the exhaust valve faces ceramic coated for extra detonation insurance.  Make sure the pistons you pick keep the compression ratio under 10:1 for use with the blower. Build the hell out of that 4L60E, and remind your tuner, that's what your running.  If you have the G80 rearend, swap in a Trutrac differential, and (assuming stock tire height) put in some 3.73s while you're in there.  Use a stronger cast cover, such as this  http://www.bmracing.com/products/70502-cast-aluminum-differential-cover-for-gm-82-85-86/.


You might be better off though finding a LQ4/4L80E combo and swapping both together.

Some good ideas. Not sure I can do the LQ4/4L80 as a package, since CA prohibits HD to LD swaps. However, the LQ4 was offered in the Yukon/Sierra 1500 Denali. I would think the wide LSA on the LS9 cam wouldn't cause many issues with emissions. Also, from what I've read, Lingenfelter actually quit using their own FE cam, and actually started using the LS9 cam. I may just stick with the stock cam, since I've heard most FE applications generally like a milder cam. My goal (whether or not it's realistic, considering the CA restrictions) is 500 rwhp. From what I've seen, 450 rwhp from a blown 6.0 is pretty easy.
 
igotzzoom said:
Some good ideas. Not sure I can do the LQ4/4L80 as a package, since CA prohibits HD to LD swaps. However, the LQ4 was offered in the Yukon/Sierra 1500 Denali. I would think the wide LSA on the LS9 cam wouldn't cause many issues with emissions. Also, from what I've read, Lingenfelter actually quit using their own FE cam, and actually started using the LS9 cam. I may just stick with the stock cam, since I've heard most FE applications generally like a milder cam. My goal (whether or not it's realistic, considering the CA restrictions) is 500 rwhp. From what I've seen, 450 rwhp from a blown 6.0 is pretty easy.

I am not sure if this matters, but the first generation EXT's all came with the LQ9.

But you probably already knew that.
 
I remember asking this some years ago, and was told the LQ9 is probably a great bet for our vehicles. Not sure what you mean by "California doesn't allow LD to HD swaps."    I've not heard this.  I assumed any engine could go into any vehicle as long as emissions controls were retained.  For example, I could (legally if not practically) put an 8.1L Vortec into my '00 Jetta.
 
PerfectReign said:
I remember asking this some years ago, and was told the LQ9 is probably a great bet for our vehicles. Not sure what you mean by "California doesn't allow LD to HD swaps."    I've not heard this.  I assumed any engine could go into any vehicle as long as emissions controls were retained.  For example, I could (legally if not practically) put an 8.1L Vortec into my '00 Jetta.

https://www.bar.ca.gov/Industry/Engine_Change_Guidelines.html

"Don't mix engine and vehicle classifications which will degrade the emissions certification standards. For example, a heavy-duty engine cannot be installed in a light-duty exhaust-controlled chassis even if they have the same displacement. Non-emissions controlled power plants such as industrial or off-road-use-only engines may not be placed in any exhaust-controlled vehicle."
 
igotzzoom said:
https://www.bar.ca.gov/Industry/Engine_Change_Guidelines.html

"Don't mix engine and vehicle classifications which will degrade the emissions certification standards. For example, a heavy-duty engine cannot be installed in a light-duty exhaust-controlled chassis even if they have the same displacement. Non-emissions controlled power plants such as industrial or off-road-use-only engines may not be placed in any exhaust-controlled vehicle."

Both LQ4 and LQ9 were used in light duty AND heavy duty truck applications (although not available in the Avalanche).  The only HD engine for the Avalanche 2500 at that time was the 8.1L.

https://en.wikipedia.org/wiki/LS_based_GM_small-block_engine

On a side note, that link just screams, "this is why CA can't have nice things."  It's a beautiful state with excellent weather, but how anyone puts up with all the legislation b.s. is beyond me. 
 
Bigtrucklover said:
, "this is why CA can't have nice things."  It's a beautiful state with excellent weather, but how anyone puts up with all the legislation b.s. is beyond me. 
Beats me too! My son is sixth generation and he's dying to get out. My wife and I often talk about how soon we can retire and get out of here. 
 
Yeah. It's an unfortunate reality I have to deal with for the time being. But I'm always up for a good challenge, and this is certainly one of them.
 
Check this out if you already haven't.
http://www.trucktrend.com/how-to/engine/1208tr-5-3l-bow-tie-builds-mild-to-wild/
They got 603 hp @ 6,400 rpm and 544 lb-ft of torque @ 5,400 rpm from a naturally aspirated LM7 by stroking it.  Also look at a 4l80e swap the 4l60e wont last a second with that much power.  If you can do the tranny swap yourself it will only cost around 2-3k.  Check this out for instructions on the 4l80e swap.
http://www.ls1truck.com/forums/front-page-news/14163-how-4l60e-4l80e-trans-swap.html
Good luck with your build.
 
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