well if i go used LS1 chances are im going to find one with way more miles on it then my 4.8 what am i going to have to do to make sure it runs like new and not give out on me at all? also will an LS1 bolt up to my 4L60 with no problems? (im assuming i have a 4L60 its an 03 SCSB without tow package)

 

In my opinion, LS1's are very overpriced. People still want $2500+ for an LS1. You can get a 6.0 for half of that. The 6.0 has better heads and a 4" bore which in my opinion is a lot better since all of the General's performance stuff is now on a 4" or bigger bore. Also, since you don't have the tow package, at least get a tranny cooler.

 

Agreed

 

how much are the 6.0s goen for? LQ4, LQ9, LS2 etc. and will they bolt up to a 4L60 with no problems?

 

You live in Miami Florida...there's got to be someone with an F-body selling his/her LS1. High mileage on these new motors means very little. If you get the engine at a cheap price because it has 150k+ miles, all one needs to do is hone the cylinders .010" over and slap in $300 dollar OEM replacement pistons from Speed Pro in a +.010" oversize. The machine shop doing the work will replace the 2nd thing on the list of high miles, which is the cam bearings. For about $500-600 plus pistons you could have a brand new short block. I'd build the V8 as money and time allows and swap in a built LS1 with goodies rather than a cheap low-mileage stock LS1. Turn it into a project to work on when there's nothing on TV while you keep driving the 4.8L now, then after a few months swap it into your truck and tune the PCM for the 5.7L.

 

well lets say i go 6.0 or 5.7 like you say and i bring it restore it to new what kind of gas mileage am i looking at city/highway? and how much ballpark figure would all the machine work and new parts for the new motor run me?

 

I wouldn't worry too much about gas mileage

With the 4.8 I usually got around 14 city. The worst tank I ever got was 10 mpg. With the 6.0 I've filled up twice where I calculated it, and both times I saw mid 13 mpg. That's with me taking it easy. I floor it once every eon LOL. Well, it did have 2 dyno passes on it, and 1 seafoam treatment where I went wot about 5-6 times.

As far as highway mileage, the 6.0 gets better than the 4.8 because it NEVER kicks out of OD. It's actually one of the things I don't like about the 6.0 (it's actually in the tune more than anything) is the fact that it's really hard to get the engine to kick into 3rd on the highway.

 

well thats one thing i love about my 4.8 the way i drive it im getting about 17 city. all i do is when i see a red light ahead i let off the gas and just cruise to it and when i accelerate i try to keep it under 2k and once im up to speed i try to keep my RPMS as low as i can while still maintaining speed. works awsome for me

 

ok well heres a question, how much HP do you guys think my 4.8 will make with intake, full exhaust (longtubes no cats), e-fans, pullies, and a tune?

 

I'd say about 280 to the wheels, which is exactly what you will get with a 6.0 stock. Add in a nice cam and you should get around 300 to the wheels. I'd say at that point you will start having some traction issues.....I know I got some with the stock 6.0. The stock 4.8 could squeel em, but the 6.0 can just burn em up