CK5
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383 vs ls

Stroker or LS

  • Stroker

    Votes: 16 44.4%
  • LQ4

    Votes: 12 33.3%
  • Other

    Votes: 5 13.9%
  • Built 5.3

    Votes: 3 8.3%

  • Total voters
    36
I have full length stainless Hedman headers. I installed ORD heavy duty shackles with greasable bolts. On the driver side, all that I had to do was grind a little off the nut for the hanger. Plenty of clearance. Passenger side required a little dimple work right at the collector with a ball peen hammer. Not much though.
 
They also make a set of full length that they told me won't extend below the frame rails which would more than clear the shackles. I already had a previous set of full length headers so I went back with them to ease connecting to the exhaust system.
 
Here she is. Tomorrow I want to get it on an engine stand and strip the harness off and start cleaning it up. Also need to check if this is an lq9, or an lq4 without pulling a head...image1(3).jpg 20180311_212606.jpg image1(4).jpg 20180311_212508.jpg
 
Got the engine on the stand yesterday and it started dripping water from the oil filter, which was crushed..., and the exhaust. Looks like I'm going to need to tear into it and assess the damage. If my rotating assembly and cylinders are rusted I'm not going to mess with replacing stock for stock and will look into stroking this thing.

Also, I didn't notice but the harness going back behind the block (trans, o2 sensors? fuel pump?) was just cut. Hoping I can salvage it, but may likely need to buy a new harness. Anyone know where I can buy a pre-stripped down harness for this if that's the case?
 
How do you like your gear vendors?

My C20 has a built 406 sbc with a th400 and gear vendors overdrive.

The GV is great and allows me to cruise at 70 mph at 2400 rpm with 4.10 gear and 33" tires. The engine has great torque starting at 2000 rpm and really starts to wake up above 2500rpm and probably peaks at 4500 with a comp 264 roller cam. This truck is my daily driver and is also for towing my 8500 pound toy hauler. The GV gives me 6 gears and makes all the difference. You can't coast downhill or engine brake while in overdrive as it won't lube properly and could burn up. Empty, I will use light throttle or very short periods of coasting and with a load I stay in 3rd down hills, or 2nd with the trailer.

The 6.0 is the way to go. I'm tired of dealing with a carb and the fact that it likely doesn't have an ideal tune for much of my driving. A FI setup would be much better for always getting as much power as possible.

I probably have $6k into my engine with a roller conversion being almost a grand, a forged and precision ground crank, a couple grand into aluminum heads and intake with porting, an hei billet dizzy, then add in headers that were about 600 bucks back in 2001 and all the other crap to match. A magazine article claimed 525 tq from a very similar 406.

Cry once with the electronics, fuel system, and other crap but if I was in the same position, I would go with the 6.0. A small supercharger would be an easy was to make big and reliable power and probably for less money than what I have into the 406.

Diesel is the way to go for torque and I agree that old muscle sounds the best. Diesels can sound good and sometimes be less obnoxious sounding while still sounding mean when you get on it. I hate the sound of the 2005 5.3 chevy trucks. The starter sound is annoying (not like the gear reduction starter on my 406) and the stock exhaust is quiet but also annoying. When the 406 has a flowmaster super 44, it sounded insane and it was also nasty with a 40 series. I can't take that drone anymore and went to a 70 series, which really surprised me. My k5 has a new crate 350 tbi and a 70 series and is quiet and ok sounding. The 406 is night and day difference with the same muffler and while tame, people still can tell it isn't a stock engine.
 
Good news is that for the most part the drivers side is fine, just a little surface rust in #7, nothing a little hone can't handle. Still need to pull passenger side and get the rotating assembly out.

Is the extra compression worth replacing the pistons (assuming these ones are fine) for flat top or even dome?

20180314_184130.jpg

20180314_184134.jpg
 
Good news is that for the most part the drivers side is fine, just a little surface rust in #7, nothing a little hone can't handle. Still need to pull passenger side and get the rotating assembly out.

Is the extra compression worth replacing the pistons (assuming these ones are fine) for flat top or even dome?

View attachment 259954

View attachment 259955
You need to know the volume of the dish of the piston in order to calculate your static compression. You need the specs on your cam to calculate your dynamic compression. That is the magic number determining whether you will detonate or not. Deck height plus compressed head gasket thickness totaling forty thousandths for proper squish.
 
You need to know the volume of the dish of the piston in order to calculate your static compression. You need the specs on your cam to calculate your dynamic compression. That is the magic number determining whether you will detonate or not. Deck height plus compressed head gasket thickness totaling forty thousandths for proper squish.

They're the stock dish pistons, was debating whether putting the lq9 pistons in would be worth it.
 
Lq9 is above my pay grade. Not familiar with them. It all boils down to cam selection, compression ratio, header size/design ie: shorty, full length, heads, etc...........

What are you aiming to get out of it. Torque off the bottom end, horse power off the top end, fuel economy, good towing....

Many factors go into a good engine. All things have to work together to have a good setup.

You can spend all kinds of money and still end up with a piece of junk.

Much to think about.
 
Lq9 is above my pay grade. Not familiar with them. It all boils down to cam selection, compression ratio, header size/design ie: shorty, full length, heads, etc...........

What are you aiming to get out of it. Torque off the bottom end, horse power off the top end, fuel economy, good towing....

Many factors go into a good engine. All things have to work together to have a good setup.

You can spend all kinds of money and still end up with a piece of junk.

Much to think about.

LQ9 is just the HO version of the LQ4, which is what I have, the only difference being flat top piston vs dish. Anywhere from a 20-45 hp bump and increase from 9.4:1 to 10:1 compression

Some reading :)

http://www.hcdmag.com/60l-vortec-engine/
http://bdturnkeyengines.com/60l-lq9-vs-lq4/
 
The difference between LQ4 and LQ9 is the flat tops vs dished, and the cam. I don't think the half point of CR is gonna be much of a game changer like a cam swap would...
 
Just got approval for funds from the boss, this may have just turned into a 408 stroker build. Getting my stroker and an LS all in one :)

I know this was supposed to be a budget build...but...
 
Don't do the stroker kit. The liner length isn't long enough to keep the piston skirt from coming out the bottom of the liner at the bottom of the stroke. Really bad wear issues with those...

Skip to 8:43

 
The cubic dollar build...

LSNext block, 457" 8900 rpm red line. 1100 hp naturally aspirated, no boost, no drugs. Heads flow 490 cfm.
 
So far my engine build is looking as such:

-Either milled and ported 317s (want to get chamber cc down a bit) or stock 243s.
-flat top pistons
-stock cam? Haven't figured one out yet...
-stock bottom end
-Holley HP
-87-91 blazer tank (baffles worth the swap?) with sender and '97 vortec pump (internal pump worth the changes?)

still need to go through and check clearances and that everything will work together.
 
For cam ideas...read this.

http://www.hotrod.com/articles/ls-cam-test-comparison/

It's interesting with a direct comparison with all the stock cams, then at the end they try three Crane cams...with some great results. Bear in mind the test mule is a 5.3. With a 6.0 the numbers will be 13-15% higher.

I think I have it then (minus red):

-Either milled and ported 317s (want to get chamber cc down a bit) or stock 243s - if I can find any for a decent price.
-flat top pistons - https://www.summitracing.com/parts/slp-h1129cpa/overview/ (not boosting, so hypers should be just fine)
-Crane Cam HR-206/294-2S-14.55 - want to call and see if they still have the 200deg cam from your article.
-stock bottom end
-Holley HP - https://www.holley.com/products/fue...ion/hp_efi/ecu_and_harness_kits/parts/550-602
-87-91 blazer tank (baffles worth the swap?) with sender and '97 vortec pump (internal pump worth the changes?)
-Shoenfield longtubes (already setup for longtubes, would require less changes in exhaust) - https://rover.ebay.com/rover/0/0/0?mpre=https://www.ebay.com/ulk/itm/192119936298

This should put me at an 11:1 compression ratio and is basically an LS2 with an iron block and different cam.
 

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