building a new engine?

[vonrottes]

I knew it would happen....after I went from the 2.8 to a 4.8 I still want to go faster.... Not a lot faster....just a little bit....

 

And since I don't have funds/transportation or anything else really to tear my truck apart and rebuild the engine... I'd like to build a second engine.

 

Ideally I'd like to get about 400whp more is fine.

don't want anything crazy since I want it to run on pump gas since it will remain a daily driver.

 

 

But here is my idea:

Firstly I want to build this as a 4.8 so I'm keeping the stock Stroke/bore

 

"bolt-ins"

JE 7.5 dome pistons

LS6 intake

Scorpion roller rockers

new "stock" lifters & retainers

No idea on cam/springs yet

Cometic .030 MLS head gaskets

ARP everything!

 

Machine work

Balance the rods within say .5gram

port/polish & Mill the heads down just a little 60cc chambers (should be right at 11:1)

port/polish the Throttle body

 

Does that sound like it would make 400hp?

[aussiek2000]

A good set of heads and cam should do 400

[vonrottes]

A good set of heads and cam should do 400

 

on a 4.8 making 250hp stock?

[STEVE-O]

Your trying to do it the hard way, just replace the 4.8 with a 6.0, or visit it

[vonrottes]

Your trying to do it the hard way, just replace the 4.8 with a 6.0, or visit it

 

But I want to keep the lower displacement so it will rev higher, faster.

 

I know it sounds weird, but I just like the sound of fast revving engines.

and with a 83mm stroke and 96mm bore.

rebalancing the internals, upping the valve train and doing some stuff to just straight up make more power....

 

I don't see any reason why a built 4.8 couldn't spin up to 7,500 and get there relatively quick.

[Chadz89GTA]

I spin my ls1 to 7400 and I'm sure it's seen 7500+ quite a few times as well. Stock newer style rod bolts and pac 1518 springs, made 400 even on stock untouched 241 heads.

[aussiek2000]

on a 4.8 making 250hp stock?

 

4.8 as in LS based truck motor? There are plenty of Heads/cam/intake making over 400. You will need to spin higher RPM to get the most out of it.

 

My 6.0 will be making 540-550 crank HP in a month or so on Heads/cam/intake/bolt ons and they only came with 360

[Chadz89GTA]

Keep the 4.8 crank and punch it to ls1 bore.

[vonrottes]

4.8 as in LS based truck motor? There are plenty of Heads/cam/intake making over 400. You will need to spin higher RPM to get the most out of it.

 

My 6.0 will be making 540-550 crank HP in a month or so on Heads/cam/intake/bolt ons and they only came with 360

 

Yes just a standard LR4

 

So I'm still lost on a cam and springs.

But what about ported/polished 799 heads milled down to 60cc combustion chambers?

[aussiek2000]

Hot rod made 451 on a 4.8 before going to turbos. Note the arcticle says 5.3 but they later find out at the end it was a 4.8

 

 

http://www.hotrod.com/how-to/engine/hrdp-1109-stock-gm-ls-engine-big-bang-theory/