6Ltr 307 or 6.2Ltr 317?

[CarLad97]

I'm struggling at the moment aside from a small rwkw boost finding a huge difference between the 2007 6Ltrs 307 and the 2008 6.2Ltrs 317.

Stock out of HSV with out any other mods, which is the smarter buy?

 

[lmoengnr]

I'm struggling at the moment aside from a small rwkw boost finding a huge difference between the 2007 6Ltrs 307 and the 2008 6.2Ltrs 317.

Stock out of HSV with out any other mods, which is the smarter buy?

LS2 or LS3? Your choice!

 

[shane_3800]

LS2 is better on the street with the right mods as the cathedral ports have better mid throttle reponse. The LS3 has more power if done right with the right mods will always out power a cathedral port engine. The LS3 has a better factory intake too but on the LS2 you get a massive gain using the FAST intake compared to a megar gain on the LS3 with the FAST intake.

 

[shane_3800]

I will also add the cam setup on all gen 4 stuff is better imo but you can't use aftermarket solid timing sprokets on the gen 4 stuff.

 

[CarLad97]

Is there any noticeably huge difference between the two in sound/performance with mods? For example a 6Ltr and 6.2Ltr fitted with a stage 3 cam or bigger alongside a supercharger.

Iv'e heard or been told, that a worked 6Ltr will go a lot harder then a 6.2Ltr, Iv'e also been told the opposite so I'm all over the shop with a conclusion.

 

[shane_3800]

If you were to supercharge I would just go the LS3 and the biggest (reasonable) cam. In other words it will be okay to sacrifice some low end with a supercharger. Unless centrifugal then you want a cam with a little more at the bottom because centrifugals have a rising boost curve.

 

[Heron SSV]

LS3's have better heads, with square ports, similar to the L76/L77/L98. LS2 heads are similar to LS1's, they're cathedral ports. Square port heads flow better, especially with forced induction. A cheap upgrade for LS2's back in the day were to put a set of L98 heads on for a little extra power. LS3 intake manifold flows really well for a factory part, they handle well over 1000hp on a turbo setup easily.

Power wise, there will be small difference (lower) for and LS2 compared to an LS3 with the exact same mods, it'd be barely noticeable on the street. Sound will be the same, the exhaust setup will determine what it sounds like. Most supercharger kits cater for square port heads rather than the older heads.