Jwright41

iTrader: (2)

Is there any difference between the two forged internals as far as power making goes?

rwb

If you are looking at something like the lunati kit then NO. The only real difference is the stroker crank.

blue00ZZleeper

iTrader: (5)

That depends on what your goals are, what your preference is. A lot of guys tend to steer away from big stroke motors because of how far it puts the piston skirt at BDC. They tend to "rock" and side load a little more causing excessive wear and leading to increased oil consumption. Does this happen right away, not really if its built right. If your looking for a slight increase in cubes, why not look at a LS2/LQ9 based 370? What are your power goals and what do you use the car for mostly?

The Alchemist

iTrader: (19)

Well, if I had to do it all over again, I would have gone with more cubes. More cubes means less boost needed to make a certain power. In simplified terms, same motor, same cam, heads, exhaust, with the same size pulley on the blower, the 347 will see more psi of boost than the 383, but won't be making anymore power.

So 500rwhp at 7psi is better than 500rwhp at 12psi of boost since less boost pressure is less heat. Plus it allows you to spin the blower higher at less boost pressures before you have to go to a 3-bar map and tune.

Jwright41

iTrader: (2)

Goals are a weekend car that might see the track once or twice a year. More of a street machine so want good manners - I know it deals with the tune as well. What I am looking into as for parts is TEA Stage 2 243 heads, Tick blower cam - 226/234 | .59x"/.61x" | LSA115+3, Siemens 60# injectors and D1SC with 8 rib and 4.5 twin coolers. Exhaust will be 1 7/8 headers and true dual 3". Goal is 550-600. From what I have read on here you can do this on the stock engine but I would rather not have to worry about breaking anything and revisit the engine. Want to do it once and do it right.

Papa Wells

I would say forged 347, but that's just me.

dschmittie1

iTrader: (64)

600 is very easy to make with a 347 even with stock heads. I made 676 with my old 347 with 241 heads and 13ish psi when I had a D1.

That being said I know of 3 cars that have made 650-670 rwhp on stock short blocks.

but lets be honest. You will likely want more power than 600 and if you have the money to build a 383 vs a 347 why not build the 383

NicD

iTrader: (7)

Cubes will bring your powerband in sooner and make more torque especially with a procharger.

Papa Wells

An LQ9 408 can also be a very good budget motor and is very popular.