Im pretty sure the 5.3 in my truck is toast so now right now Im tossing around three ideas.

1. bore the cylinders on the 5.3 I have put forged pistons in it arp rod bolts and head bolts, p and p the heads valve job and all that stuff which will give me a 330 and cost me about 1400.

2. bore the cylinders stroke it and put a forged rotating assembly in it then the heads stuff above that will give me a 374 for 3000 and I can spray a 250 shot on it and not worry about it.

3. buy a 6L lq4 put some 5.3 heads with all the good stuff done to them and enlarge the combustion chambers to 72cc so I will have about 10.1 CR put rod bolts in it and I will have a 364(or whatever a 6L ci is) for about 2000 and be able to spray a 150 shot pretty easily.

Option one is the cheapest and will net me about 400 crank hp probably. Option two will net me about 480 or so and be able to spray the **** out of it. Option three is economical also and will net me 460-470 hp but I wont be able to spray as big of a shot and it will lack the torque that the 374 would produce. What would you do?

I want something that is going to be dependable and all my new valvetrain stuff will go into whatever engine I build. The only thing I would change is if I went the 374 route I would get a different cam. I realize spraying a 250 shot would eventually cause problems on even a forged engine but that would only be for the track I would probably spray a 175 shot all the time. I realize I would need a higher volume fuel pump and all the supporting stuff but I am just talking dollar for dollar what is going to be the best combination. Going the 374 route will take another month atleast to come up with the money.

 

Nobody has any help to give me to make an informed decision or what?

 

I like the idea of option 3. What happened to your 5.3?

 

Think I fried a piston ring not sure yet Ill find out tomorrow when I do a compression test on the cylinders and see what the deal is.

 

Were you spraying it when the problems started???

 

If youve really killed the 5.3 and are gonna go through all that trouble I would do it right and at least do a h/c 6.0

you could have 450 at the wheels instead of 350

for an extra 1500 thats cheap for 100 rw more I think its worth it plus youve got something to build on also.

my .02

 

looks like you want to spend 1400 to 3000.

if the 5.3 still runs good enough to get you around.
salvage a 6.0 block and start building a 408 or a very strong 6.0
6.0 crank and rods are good with arp blots, forged pistons for extra strength.
every thing else you put in to the 5.3 can swap over, that's less stuff to buy.
your tune will need a small upgrade, your cam will kick out more hp with the extra cubes.
compression will be higher with the 5.3 heads, maybe 10.6 - 10.7
6.0 block. new bearings, arp bolts, 010 forged pistons LQ4, new rings and a little machine work.

trying to save a few bucks and increase hp.

 

Option 4, bore and stroke a 6.0 to whatever, forged internals, headwork, and then a 250 shot on top. And better go ahead and upgrade to a FLP Level 5 4L80E...

 

A buddy of mine is going to look for a 6L short block today for me. 10.6 is too high for daily driving I dont want to have to run race gas all the time. I would get the combustion chamber on the heads enlarged to 72cc which would give me a low 10 CR. If I go the 6L route I will put a set of je forged pistons in it, go with a little bit different cam and sell mine, get some head work done the 5.3 heads I have and put arp rod bolts in it. Ill know more about what Im going to do when I do the compression test after work today and find out how much a 6L short block is goign to cost me. Vortec350 I have been spraying on it but I dont know exactly when it started smoking bad cause I drove from texas to alabama and aparently somewhere along the way something happened it was smoking a little bit before but now it is like a smoke screen when I start it up and it runs rough as hell and makes weird noises that it hasnt made before so I think its toast.

 

damn, sounds like your going to be down for a while until you get the new motor built.