Differences between LS3's:, 317, 325, 340.

[FFAman]

With MY16 SSV Redline out later this year and rumored to contain the LS3 I have 2 questions, 1) what state of tune will it come with and in a broader sense 2) what are the practical differences between the 317, 325 and 340?
hardware or just tune.?

 

[GenFSVR8]

The 340 in the R8 SV uses the same headers off the GTS plus the same bimodal air intake.

 

[FFAman]

So the difference between a 317 and 325 is tune only?

 

[Reaper]

Exhaust. AFAIK tune is the same.

 

[FFAman]

Exhaust. AFAIK tune is the same.

Cool, how is the exhaust different?

 

[PIR4TE]

So the difference between a 317 and 325 is tune only?

Yes, both tune and catback. The laugh is that the first thing people with the SV do is rip off the special exhaust and intake!

See the output figure is just marketing, the reality is there is virtually no difference when you tune any Aussie GenIV V8 with proven bolt-ons (see below):

6.2 mildly tuned with bolt-ons (DIY or Walky or Harrop) gets minimum 340 kW at the fly,
6.0 mildly tuned with bolt-ons (DIY or Walky or Harrop) gets minimum 305 kW at the fly.
This is due to a few minor differences, mainly valve events and compression.
6.0 custom tuned by expert with bolt-ons gets max 355 kW at the fly.
Sticking with bolt-ons you can equalise the 6.0 vs 6.2 compression by shaving 0.030" for about $800, and set to same valve events using replacement rockers for about $1200. Then the power rating comparison of LS3 to L77 evens up:
6.0 custom tuned by expert with bolt-ons, better combustion on e85 gets 370 kW at the fly. Whereas 6.2 already has OK valve events, compression, would only be marginally different due to being 0.030" (four human hairs or a flaccid bee's dick) wider bore.
So in terms of outright performance without opening the motor, the LS3 is better out of the box, but given good tune and bolt-ons (spend a couple grand more on the 6.0) and the difference is marginal. Fastest GenIV NA builds are 6.0.

 

[lmoengnr]

317 uses same cat back as SS/SSV with HSV mufflers.

325 uses 2.5" cat back (same as E series GTS).

340 uses above exhaust, with Bi-modal intake and exhaust.

 

[Ian Johnston]

So, E3 GTS cat back exhaust is different to E1 GTS. My E1 has 2 1/4"pipes, not 2 1/2" E1 is same as VE SS/SSV.

 

[Reaper]

So, E3 GTS cat back exhaust is different to E1 GTS. My E1 has 2 1/4"pipes, not 2 1/2" E1 is same as VE SS/SSV.

E3 GTS has 2 1/4" rear cans and 2 1/2" pipe in the mid section. The 325 mid pipes are very different to the SSV and 317 pipes (just look at the crush offset bend in the middle and you will cringe and immediately ditch the Holden pipes. 2 1/4" bimodals with a bit of pressure going thru them sound great.

Yes, both tune and catback. The laugh is that the first thing people with the SV do is rip off the special exhaust and intake!

near certain the 317/325 tune is the same.

 

[XUV]

317 uses same cat back as SS/SSV with HSV mufflers.

325 uses 2.5" cat back (same as E series GTS).

340 uses above exhaust, with Bi-modal intake and exhaust.

View attachment 176908

plus Holden (and QANTAS) have a love of the number 7 and it'll be in the power figure in some way 317, 32+5=7, 3+4=70
and the real power figure wll be there abouts.