nope 45hp diff is correct, but a tune can make a world of difference

the motor you have is fine

 

should i think about upgrades to get a tire burner or should it be strong enough stock?i do have 3.73 and id like to keep up with my wifes escalade lol

 

Alot of the LQ9's extra HP comes from the PCM tuning, along with the higher compression. An LQ4 6.0 is plenty powerful, especially with some supporting mods. First thing that I'd do before bolting that bad boy in is to find a cam that suits your needs, get some strong valve springs and push rods, bolt er in, get it tuned and let it rip!

 

lq4's were rated between 300-335 hp depending on application.

lq9's were rated at 345 in all applications.

 

I am going to get the lq4 becuase of the lower compression for a turbo application, but if you were gonna keep the truck n/a then i would imagine you would want the higher compression higher hp lq9. Now obviously a tune would help a lot, but just stating somehting. Any 6.0 is gonna be great, i can't wait to buy mine, i'm jealous.

 

agreed a cam will be much easier to install before the motor goes in the truck

 

normally sellers are commanding higher prices for the lq9 than the lq4 and for many its not worth the extra money for that little bit of compression bump, you could probably mill the heads to get the difference in comp. for less than the diff in cost

 

can you tell by the vin if so how i do have the vi n# the place i got it from said i could go on the gm site and find out is that true and if so does anyone have the link to site .or i can give youguys the vin

 

I have the username and password to GMDealerworld, so shoot me the vin and i'll try and find out. I know if you go to car-part.com they ask for the vin of the motor, but it doesn't say lq4 or lq9. I'll try and go into engine build and see if it gives me the number, shoot me the vin and i'll try right now.

 

The LQ4 is rated lower but, compared to your 4.8 it's a torque monster. All the LQ4 needs is a nice cam and a MP122 and it will make good power and break trannys.