Can the Cam?

[426Cuda]

I worked out the HSV headers and cats were pretty restrictive on the Maloo, when they were replaced by decent headers and cats.
They 'unlocked' a shedload of torque all the way through the rev range, and that was before the tune.
Took 4 days of driving before the CEL came on...

I think it's the cats and the entry angle more than the headers. I think that is where the cheap easy gains are.

 

[abuch47]

I think it's the cats and the entry angle more than the headers. I think that is where the cheap easy gains are.

But guarantees a needed tune unless you get a better design but still 400+ cell which seems to defeat the purpose

 

[rognvald261]

But guarantees a needed tune unless you get a better design but still 400+ cell which seems to defeat the purpose

You don’t need to alter the stock tune with factory cats. The bigger problem is confined space actually, as above that means obtuse entry angle to cat substrate and zero downpipe length as secondary (collector).
400 cell cats are not an issue, all modern cars have Euro 5 spec with high catalytic efficiency long life and performance.
Plenty of 10s NA LS cars with 400 Cell or otherwise compliant cats.

 

[426Cuda]

But guarantees a needed tune unless you get a better design but still 400+ cell which seems to defeat the purpose

As above. 400cpi cats may be flow restrictive. But, with a better designed entry, good gains are still there to be had. A tune is a must and very desirable with HFC's though.

 

[lmoengnr]

As above. 400cpi cats may be flow restrictive. But, with a better designed entry, good gains are still there to be had. A tune is a must and very desirable with HFC's though.

Are they 400cpi cats? I did read somewhere that Euro 5 were 600cpi, but cant confirm that...
Has anyone actually eyeballed the substrate in a VF2 cat?
I was under the Magnum yesterday and compared the cat to a Euro 4 HSV cat, the Euro 5 is 'physically' smaller.

 

[blackve76]

But of thermal dynamics and monster pirate schooling required

Ve/VF cats flow quite well due to there size the exhaust gets through easy, put a small 100cpi cat in won’t be a massive difference.

Early VE SS 6litre times (2007)and I had short pacemaker headers with std cats to 2 1/2 system with 224 230 cam made 325rwkw on dyno dynamics, add 4>1 packed 100cpi cats 3” system I gained 8kw from memory.

 

[dimetime]

dont forget about torque and sound guys, its all good to have a high hp/kw number but if the car drives terrible and sounds terrible then the kw doesnt really matter

 

[monty_vfssv]

But of thermal dynamics and monster pirate schooling required

Ve/VF cats flow quite well due to there size the exhaust gets through easy, put a small 100cpi cat in won’t be a massive difference.

Early VE SS 6litre times (2007)and I had short pacemaker headers with std cats to 2 1/2 system with 224 230 cam made 325rwkw on dyno dynamics, add 4>1 packed 100cpi cats 3” system I gained 8kw from memory.

8kw peak or accross the board?

 

[bbunnys]

Would someone comment on how they find highway cruising with a cam in the VF2 LS3. Mainly in regards to fuel economy.
Currently have a W375 with custom tune (manual car) and not interested in supercharger (out of budget). But from reading several threads in here, I think a cam could be a goer to get a bit more power from the NA engine. Seems like 224/232 114lsa, maybe like Harrop H02 seems like a good option. From what people here are using.

In NZ im running 100 octane, which is quite new here. I have a holiday house which is a 500km round trip from the nearest servo with 100 octaine or even 98. Currently no issues getting that distance on a tank with the W375 tune. But if cam uses much more fuel at highway speeds. Could be a distance issue.

 

[blackve76]

8kw peak or accross the board?

Peak all gains above 3500rpm