FirehawkSS

iTrader: (2)

I bought a lq4 2004 chevy silverado motor this fall and have decided to swap it into my 87 firebird. Here is one of the mods that I have done to this engine.

I decided to go with the ls6 valley cover on my lq4 for the better ring sealing and less oil consumption. Also to clean up some of the pcv tubes all over the engine.

Next I decided to go with the ls1 steam tubes for their preferred cooling ability. I will be doing some road racing and you all know how sensitive third gens are to overheating. I've read that the ls1 steam tubes will help remove the last little bit of air near the back of the engine.

I also want to run the ls6 intake manifold with this setup. There is an inherent problem with this because the floor of the ls6 intake manifold is lower than the floor of the ls1 intake manifold. This is why the ls6 manifold has to be used with the ls6 steam tubes. Plugs in the back and a crossover on the front. Ls1 steam tubes will not fit under an ls6 manifold.

Well actually none of these mods should work together. Somehow I managed to make them work though. Here is how I combined all these mods into a truck engine! LOL! Yea talk about a frankenstein project. Check it out.

FirehawkSS

iTrader: (2)

First buy an lq4 motor

Second remove truck manifold

Third strip and clean

FirehawkSS

iTrader: (2)

Next remove truck valley cover and install ls6 valley cover. You can see in the picture above that I have already done that. There is no tab that needs to be ground off on the lq4 motors. So the ls6 valley cover fits perfectly. I reused the valley cover gasket because it looked like it was in great shape.

Check out these pics of the valley cover installed. Notice all the nice round areas that protrude out from the valley cover. These will end up causing you problems!

FirehawkSS

iTrader: (2)

After that is done take the ls1 steam tube and place it on the valley cover. You will find that not only do the tubes hit the round things but they also hit the pcv pipe coming from the cover. You will need to copy my steam tube routing exactly to make it work. If you can find another way please post a pic because this took about 4 hours of work.

I bent a little at a time and refit the tubes. Each time I bent the tubes i would get a little closer then take them off again and rebend. But sometimes you would make it worse before you made it better. Have confidence in your bending ability and try to think a few bends ahead. Plan each bend carefully and don't over bend in one spot or you will kink the hose.

I used everything I could to make tight bends and large bends. I didn't use a tubing bender. Work the steam tubes around round objects only. Nothing sharp because that will cause a kink in the tubes. I used a 1in diameter bar locked in a vise to make the large radius bends and a screw driver shaft to make the tight bends. You can also use your two thumbs if you are extremely careful. Enough talk just make sure you don't work one area too much or it will break or kink on you.

Now keep in mind you will also have to make sure the mounting pads at each end of the tube fit into their respective places. The angle must be correct as well for proper sealing and mating with the heads. This is harder than it sounds.

FirehawkSS

iTrader: (2)

So why do the tubes need to dodge all the round things and the pcv tube? Well they need to do this because the ls6 intake manifold will leave you no clearance whatsoever. You can use the ls6 intake manifold with the ls6 valley cover obviously without any problems. But remember i'm using the ls1 steam tubes instead of the ls6 steam tubes. Look at the first set of pictures and you will see the lq4 steam tubes installed on the engine. That is similar to the ls6 setup.

Anyways since there is no clearance with the ls6 intake you must make clearance. There are stiffening ribs on the bottom of the intake that must be removed so that the manifold can be used. You have to be brave as well as crazy to take a right angle grinder to your ls6 manifold. I was very careful with my grinding. I made sure to only take off the rib material and in no way gouge into the manifold floor. You will also have to peel back the foam and grind on the ribs there. Once done you can re-glue them to the manifold. I started with a little at a time but then said screw it and ground most of them off.

FirehawkSS

iTrader: (2)

After this is done you will be able to mount the ls6 intake to the heads. I did a dry run and installed the manifold and it fit amazingly well. Look how close everything is though. It in no way touches any part of the intake manifold. It will fit with patience and multiple attempts.

Front of engine

Passenger side

Drivers Side

Back of engine

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Was it worth it? I think it was but you judge for yourself. At least you know what you are in for if you try these mods together.

blk91rs

Saw your post about installing an ls6 intake on an LQ4 block.

Looking to do something similar.

I was wondering what serpentine setup you used? Did you use a ls1 and ls2 set up? or did you use something similar to this link with a modified waterpump and bracket

http://www.performancetrucks.net/for...ries+speartech

InfernalVortex

iTrader: (4)

Im just curious, why would changing the lifter valley cover reduce oil consumption or have an effect on ring sealing?

I've got a 5.3 in my truck. I always thought about yanking it and throwing it in the RS... But at the end of the day it'd be a lot cheaper and easier to just grab another one. But I dont know nearly as much about LS motors as I do about Gen I motors.

1ADan

iTrader: (4)

the LS6 valley pan allows for a revised pcv setup to be used which is supposed to elimate or reduce some of the issues (oil consumption) that come from the LS1-derived pcv system that originally came on that motor.

techrunner

i see a lot of effort in this setup, i was just wondering why did you decide to mod the ls1 steam tubes and not just block off the back ports? my lq4 came that way (2003 engine) with just a crossover in the front. just wondering if theres anything better about using all four ports. thanks

BlueZee28

iTrader: (30)

You can trim off the "fins" on the underside of the LS6 intake without changing steam tubes or the valley cover. A friend of mine did this and it worked great, no fitment issues.

Atilla the Fun

In the beginning, (no, I'm not getting biblical) there was a problem with detonation in cylinder #7, which is where the original steam tubes came from. For my LSx builds, I decided that overworked trucks that stay at WOT for as long as 10 minutes at a time, climbing over the Rockies, East of Denver, are more likely to have detonation problems than featherweight Corvettes that only see WOT for 13 seconds at a time, so I decided to combine the LS6 valley cover with the truck steam arrangement, and it's been excellent for the half-dozen builds I've done for my customers. I did it this way on my own Fiero, too. But I'm not using any pre-'01 parts, either. Not ever. Unconditionally, NO exceptions.

blk91rs

Do you have any pics???

InfernalVortex

iTrader: (4)

Whats wrong with pre - 01 parts?

FirehawkSS

iTrader: (2)

Take a look at the above pictures and you will see where i did grind the fins off the bottom of the ls6 manifold. I was pretty happy with the fit

See what 1A Dan and Atilla the Fun posted. They are correct in the reasoning behind this project. Im worried about overheating issues and detonation. I'm running the car in the silver state classic and i see long full throttle runs. I'm also running a de-areation chamber so the vent tubes are a must on this build.

FirehawkSS

iTrader: (2)

Here is a quick pic of the serpentine setup I used. It is an f-body setup. The truck setup will also work but there needs to be some modification near the throttle body. Corvette and gto setup will also work without mods.

Check this link out if you are curious what goes into a truck setup with the ls6 manifold

http://www.ls1truck.com/forums/front...take-swap.html

blk91rs

First of all, this is a wonderful picture, kinda jealous....lol, but it looks great.

Did you use an LS1 waterpump?.....what about the alterntor?

From what I can see and guess at: You used an LS1 pan, windage tray, pickup/tube.

FirehawkSS

iTrader: (2)

You are correct on all the above. Ls1 setup all the way on a 6.0l truck block with truck heads and ls6 manifold and ls1 pan with tray and pickup tube. One thing to note I used the 6.0l o-ring for the pickup tube and not the ls1 o-ring. It felt like the 6.0l o-ring gave a better seal. I haven't measured oil pressure yet as the engine has not yet been fired with the new setup.

blk91rs

Here is something I just thought of: Does the LQ4 have a double timing chain like an LS2? And if not can you install one?

1ADan

iTrader: (4)

IIRC, the LS2 has a single chain, as its the the stock replacement for the LS1 now. It is beefier than the original LS1 chain but retrofits onto the gears with no issue.

blk91rs

So from what I understand the LS2 chain is a good OEM replacement for the stock LQ4 chain?