Hey guys I've got a question.

Which displacement would be better to build? I'm looking to make FI and of course it going into a truck it needs to make torque and as much as possible. Are there any pro's or con's to either displacement or would one suit a DD better than the other? Also I'd like to engine to be built on a 6.0 block cause I'd like to use the L92 heads on it as well....any imput on that would be apprciated. Thanks Guys!

 

370 is much cheaper, wont have to buy a new crank, its just a 6.0 bored .030" over

 

There's no replacement for displacement. But you might as well stick a 4" crank in there if you're going 383 cause they cost the same. With a 4.030" bore that will make it a 408. If keeping cost low is a priority just get the stock crank checked and balanced..it will handle 800hp. If you'd be happy with 600rwhp or so, save that $2000 on a forged crank and go 370. If you're going for a HIGH boost application..you can only make as much hp as the weakest part..forged 408.

 

go 408 if ur gonna do 383...won't cost any more and agree that cubes rule! If I did it all again I'd buy a crate mill from GM or any # of others and get the warranty that comes with it. Do ur home work before ANYTHING... whatever budget u assume, DOUBLE it. Unless ur gonna do the work urself make sure u get a running RELIABLE truck before final payment. There are no shortage of hackers out there. Talk to some of the sponsors and others as well...SLOWHAWK, Richard @ WCCH, Joe @ Left Coast, Rick @ Synergy.

 

Second thot: Get some WCCH heads, GT2-3 cam, and a Mag or Procharger blower w/ 90mm TB and Meth, and ull get 420-440rwhp out of ur 5.3 with stock internals. Below 450rwhp and torq, u can stick with the 60E (as long as its lvl 5 built), and the G80 might even hold up for a while. Moving to an 80E will gobble LOTS of ponies - and u will eventually need to change the G80. R/

 

This is the basic idea. If you're going to start with a 6.0L block then it's not really a matter of 370 vs 383 (ls1 with a 4" crank), then it's more of the question to stroke the 6.0L instead.

So in all reality the title of this thread should be 370 vs 408. In which case I'd rather keep the 370 and spend more money on the forced induction system.

 

 

boooo you suck


Just get the most cubic inches you can afford and be done. You'll be glad you did. I am getting bored with the 6.0L already and I've only had it running a month. It's fun to squeek the tires around town with but it'd be nice to disentegrate tires on command and have that off idle torque that is laughable. You need a minimum of a 408 (affordable) and run with it.

 

One should not say "there's no replacement for displacement", instead one should more accurately say "there's no replacement for CFM". It's not the size of the engine, it's a∫bƒ(Zx/5250) where x is RPM and Z is torque at x. As long as the area under the power curve for the used powerband is the same for two engines of different sizes, they will create the same amount of power and thus accelerate vehicles at the same rate. I would take a well built forced fed 370 over an N/A built 408 every single day, sorry hirdlej.

However, if the original poster has enough money to force feed a 408, now we're talking.

EDIT: Just remembered the OP wanted to know the pro's and con's of either displacement for a DD. In that case take the lesser displacement for gas mileage since a 6.0L will still propel you around town plenty fine, then boost it to hell and back.

 

Ok Mr. Engineering man.....