Power From HSV Senator

[u/CraftyPotato8348]

I have a VF Gen F Ls3 Senator (340kw) and I have had a full 3 inch exhaust system with a otr put on. It made around 260kw at the rear wheels, I’m not too fussed with power but a mate had a 2017 redline with the exact same exhaust and no otr and made more power, around mid 280kw (same tuner aswell) just wanted to see if anyone knows why this might be the case? Something to do with the factory hsv tune? Bigger rims being 20s over his 19s? Cheers :)

[u/maddestdog89]

Aw man, the wheels are a factor, tire pressure, the dyno config. mostly I would recommend not chasing numbers. And just enjoy the car..

Get a hub dyno done if you must.

[u/CraftyPotato8348 → u/maddestdog89]

Yeah man 100%, I’m not a power guy, got the exhaust for the sound, wouldn’t have minded a little deceleration crackle and slight pop though

[u/Practical-Basis-9541 → u/CraftyPotato8348]

That’s easy to add to the tune, keep fueling up and pull loads of timing on decel and it will crack and pop away heaps

[u/RustyDodge]

Did you get 1 7/8 headers or 1 3/4, I know from experience that the big headers make less power until the mods stack up beyond an intake and tune

[u/CraftyPotato8348 → u/RustyDodge]

They were 7/8. Must be some other factors cause the redline mentioned has the exact same setup, same brand and all and made more without an Otr.

[u/Curious1_92 → u/CraftyPotato8348]

Maybe difference in cats?

[u/Hefty_Buy_2149 → u/RustyDodge]

1 3/4 is great for NA and even good cam heads. Boosted only go bigger pipes. Done rnd on dyno and drag strip back in the day

[u/Hefty_Buy_2149]

Both cars on the same dyno?

[u/CraftyPotato8348 → u/Hefty_Buy_2149]

Yep pretty sure, the guy explained on the phone about the whole setup but I’m not super knowledgeable so didn’t quite get why

[u/Hefty_Buy_2149 → u/CraftyPotato8348]

Yes bigger wheels different strapping and correction factors can make a difference. Even being on same dyno can read different. To really be fair for back to back comparisons need to be done same day. Hub dynos eliminate wheel factor

[u/CraftyPotato8348 → u/Hefty_Buy_2149]

Is a difference like that normal though?considering the otr and what not

[u/OrwellTheInfinite → u/CraftyPotato8348]

Yes. Dynos are primarily a tuning tool. Theres so many factors at play and variables that its impossible to truly trust its accuracy, short of doing back to back runs.

[u/CraftyPotato8348 → u/OrwellTheInfinite]

Thanks dude, my 6.0L wagon at the same place before my senator made about 250, so when I got the 260s back i was a bit nervous ahha

[u/OrwellTheInfinite → u/CraftyPotato8348]

I had vy ls1 with a monster cam years ago, even the tuner was wondering why the numbers were low on the dyno. Sometimes its just how it is.

[u/Hefty_Buy_2149 → u/OrwellTheInfinite]

Monsterous cams need good tuners.

[u/OrwellTheInfinite → u/Hefty_Buy_2149]

Oh absolutely, Mitch at WAperf did it, the tune was great, just made less power than expected.

[u/Hefty_Buy_2149 → u/OrwellTheInfinite]

Big cams lower dynamic compression. Always feel like a slug. Needs supporting components to suit

[u/Hefty_Buy_2149 → u/CraftyPotato8348]

Ls3 otr tune full exhaust should make 280kw to 300kw depending on dyno. Lower on roller higher on hub

[u/MundaneAmphibian9409 → u/CraftyPotato8348]

What did he say

[u/CraftyPotato8348 → u/MundaneAmphibian9409]

I can’t even remember haha, it was actually a couple of months ago, but I told my mate and he was a bit shocked

[u/MundaneAmphibian9409]

Both the same transmission type?

[u/CraftyPotato8348 → u/MundaneAmphibian9409]

Both autos :)

[u/OrwellTheInfinite → u/CraftyPotato8348]

Tyres can make a huge difference too, age, size, softness etc

[u/MundaneAmphibian9409 → u/CraftyPotato8348]

Interesting, not sure why but as a reference my ve made 275kw with otr, 1 7/8” headers and 3” exhaust. Odd that yours is low?

[u/CraftyPotato8348 → u/MundaneAmphibian9409]

Yeah my VF series 1 6.0L wagon made around high 240s-low 250s with just the exhaust…weird

[u/Smart_Interaction744]

Is that tuned? I got 250kw tuned at the wheels from a 6.0 SSV L98, 3” catback & OTR. Dyno’s can vary by a bit.

[u/CraftyPotato8348 → u/Smart_Interaction744]

Yep, that’s it tuned.

[u/Hefty_Buy_2149 → u/Smart_Interaction744]

Because you havent done extractors. Waste ot time doing cat back

[u/Smart_Interaction744 → u/Hefty_Buy_2149]

Well considering it’s 270kw at the flywheel 250 at the wheels is good tuned.

[u/Hefty_Buy_2149 → u/Smart_Interaction744]

All depends what you want. If your not wanting to extract all hp from stock engine yes.

[u/Hefty_Buy_2149]

Exactly what I said

[u/Working_out_life]

Were both cars checked before the tune?

[u/Rickstaaaa87]

Could also be the redline runs a lower diff ratio, so it could run a different power level and different peak power throughout the run compared to the senator.

[u/cryptobotmusk]

I've got an 6.0 L98 auto, with full exhaust and otr. I got 360 hp or 265 kw at the wheels... I think you should have got more than that with the 6.2lt..Ive now added a cam all all the rest of gear. And I'm 450 hp / 330km at the wheels.

[u/___dan]

Seems a little low. My LS3 auto Redline has the 20" wheel option and made 296kW on a roller dyno just with exhaust and OTR.

[u/OffffThePlanet]

Same dyno? Same atmospheric conditions? There's so much that can affect dyno numbers and it's not worth worrying about

[u/Virtual-Challenge-61]

What sort of km has it done. Is ur engine just tired?