is a 6.0 from a chevy express van the same as the truck except for the intake?

 

should be, i got mine out of an 05' express, looks the same except the accessories look a lil' closer because of the shape of the van, otherwise the same but i believe it is the lq4, lower compression engine

 

The intake's are the same, but the balance tubes for the fuel line(s) are different. The only 6.0L's are either the LQ4 or the LQ9, although their are different HP ratings for the LQ4's depending what they came in. The difference in power comes from the RPM that they "rate" the power at. Since the Denali has the 3 piece engine cover, which surpresses some of the noise at higher rpm's, they spin it higher and of course rate it higher. The work trucks, which come with the single cover that is non-insulated, make more noise at rpm, so they spin them less and of course make less power. See article below:

A: All the vehicles you've mentioned, with the exception of the Cadillac Escalade, utilize the Vortec 6000 LQ4 V-8 engine. The Caddy SUV is actually fitted with the Vortec HO 6000, option code LQ9, and uses a higher compression ratio, via a piston upgrade, which brings it up from the LQ4s 9.4:1 to a 10.0:1 ratio. This explains the significantly higher power rating of 345 hp at 5000 rpm. The Vortec LQ4 engines in the other 1/2-ton GM light-duty trucks, such as the Sierra and the Yukon, only have a slight horsepower variance. The plus or minus five horsepower is due to the different exhaust systems and air intake configurations in each model. Now here comes the tricky part. Your Silverado 2500 is considered a heavy-duty truck due to vehicle weight and therefore falls under certain federal regulations, one of them being the Transportation Equipment Noise Emission Controls. There was a problem with the Chevy and GMC 3/4- and 1-ton trucks equipped with the 6.0L V-8 engine producing excessive noise. Your truck's LQ4 engine actually had its potential horsepower downgraded. It now peaks at 300 hp at 4400 rpm because it was too noisy and would have failed the test pushing more horsepower at a higher rpm. According to the General Motors Engineering Communications Department, there were also driveability concerns involved with the decision, and the downgrade was accomplished through various means including the programming of the powertrain control module. One of the experts in GM performance reprogramming is Fastchip. You can log-on at www.fastchip.com or give them a call at 918/446-3019 for further details. You can pick up the K&N Generation II Fuel Injection Performance Kit to aid intake airflow for a few more horses. I also suggest not putting any money toward exhaust modifications on the 2500 series. The factory setup appears to have a good flow, and aftermarket performance systems are showing little or no advance in power.


copied from here http://www.trucktrend.com/features/t..._truck_expert/

 

BTW, you can swap out your balance tube from your old 5.3 onto the Van intake. You may have to change your driver side fuel rail as well, as it has a vacuum operated regulator built into it. It's no big deal tho, and definately doesn't require removing or swapping the intake as long as you have the fuel rail / balance tube off your current motor.

 

Your'e kiddin' right? I'm not arguing with the article; I, myself, found that article way before you posted it today. But you're saying the engine cover is, ultimately, what makes the difference in the horsepower rating? You're kidding right?

 

alright, the one i'm looking at is out of an '05 too. is $2100 a good price for a brand new pullout? has less than 5 miles on it.

 

 

If you read it and think in depth on it you will see that the engine cover is not actually what is allowing it to spin high but is there to supress the noise the engine makes.

They do not let the engine sping up high like the escalade since it would make too much noise.

It is a different program first and mainly as well as the cover to tame the noise but I see that has a joke since who gives a bit about noise on a work vehicle.

I have to say that there is more in the higher compression, tuning, and possibly the cam even though it is not stated here.

Either one will work for a build up but if you are just slapping on in a different ride you are better off with the caddy so you do not have to bump up the compression or mess with tuning.

 

It's not the cover, it's the RPM that they are rating it at. Why does the LQ4 in the Denali make (rated) at 325 and the same LQ4 in a 3500 1 ton make 300 (rated)? It's because the Denali is 320@5000rpm (365@4000 tq) and the 3500 is 300@4400 (360@4000 tq). How do you explain the same motor making different power? The Denali, from what they say, isn't confined to the same "noise" guidelines. It makes sense to me. Dyno your truck at 4400rpm's and then again at 5000rpms and I BET you'll see a gain in HP at higher RPM's. The point I was trying to make is that the LQ4's are "rated" different in different vehicles, but are essentially the same. It's not the engine cover, you could take that off and throw it away. I never meant to incinuate it was the engine cover.

 

The LQ4 in the 3/4 ton trucks is detuned from the factory to adhere to the "Transportation Equipment Noise Emission Controls". The standards are obviously not the same for the denali's or suburbans. It's the same motor down to the cam, but just tuned differently. The engine cover has nothing to do with the noise coming from the engine.