2010 VE SV6 SIDI Manual

[ve for lyf]

what revs should I be changing the gears?

[kuzman89]

Well peak torque for the SIDI's is at 2900rpm, but it doesn't matter really, in normal day driving I change gears around 1600-2000rpm. Its driving preference really.

[TinSnips]

Depends what you're trying to achieve.

[ve for lyf]

i change it when it hits 3k - 4k is that bad? i mean i take off very slow im not yet experienced enough and i just dont want to go hard on my car

[Ed]

depends, i change at under 2000, or sometimes around 6000! haha, they are a pretty tough engine and have been tested to withstand serious strain so the odd squirt won't harm it mate.


Aim for 2500ish just casual driving though

[ve for lyf]

how do you change it so low mine is always over 3k lol? the engine on it is very stong yeah so even if i push it to 5k revs on 2nd gear wont hurt it?

[TinSnips]

You'll just get used to it. You won't hurt it by letting it rev, so long as you don't throw it against the limiter.. Just change so you're not labouring the motor. Change lower if you want to save a bit of fuel - change higher if you want a bit more fun. In a nutshell. The 6s are pretty lazy, so cruise really well - but they certainly don't mind being allowed rev either.

[ve for lyf]

nah dude never have hit limiter unless sometimes when i accedently lower it to 2nd insted of 4th and it hits 5k - 6k revs or the other day i forgot to change down to go up a hill went up in 3rd and had to gear to 2nd and it hit 5k lol

[TinSnips]

You'll get the hang of it pretty quick.

[ve for lyf]

so even if i take off fast at lights in 1st and let it rev to 5k and change it to 2nd wont hurt it can take alot?

[TinSnips]

I'd be more worried about your clutch in that instance, if you're still learning.

[ve for lyf]

what ya mean haha I normally take off slow but like hold clutch for a bit? im still learning so yeah.. just aslong as im not hurting my car idc lol

[TinSnips]

Just don't feed the revs on too hard with the clutch half in - otherwise you'll get a bunch of really bad smelling smoke and be up for a new clutch faster than you would probably like. My advice.. get smooth on the stick first... then speed things up.

[TinSnips]

And rev-matching your downshifts will help with the smooth part.

[ve for lyf]

yeah I should take it easy first thanks dude

[jamesmp]

I normally change mine at 2,000-2,500rpm. Works well for City driving. At other times, I've pushed it up to just under redline in every get to get moving quickly.


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[Ed]

5k revs isn't revving too hard at all, thats just getting the peak power haha!

[ve for lyf]

serious so even though I felt like I was hurting the car by letting it rev up to 5k revs its not driving the car hard?

[Ed]

nah man, had mine at 5k this arvo and it didn't sound like it was going too hard and its literally in the best power range for gears

[ve for lyf]

you rekon its pretty safe then ? sometimes when i change into second it doesnt sit in and makes a crunching noise ? doesnt it just burn fuel to let it rev so high?

[UFO]

I havent seen a dynograph for a stock SV6 SIDI (did a quick google, apparently Street Commodores Nov11 issue has a graph in it. Anyone seen it?), but going by Holden's website:

Peak torque kicks in at 2800rpm (350Nm), and
Peak power hits at 6700rpm (210Kw)

Ok, the general rule is that the powerband of an engine lies between peak torque and peak power... but this is further constrained by gear ratios applied to the engine itself.

Anyone got gear ratio's I can use for calculations? And an accurate dynograph would be nice too .
If I had those I'd be able to calculate an ideal shiftpoint no worries to within a 100rpm.

But in the absence of these, it's anyone's guess. I'd place a hefty bet that the torque curve on the standard block is pretty flat considering how early peak torque is recorded, and most likely drops off before 5000rpm because of the target market (mums and dads that drive like miss daisy and change gears at 2000rpm), with the idea that good torque down low and mid range with better fuel economy is more important than a higher peak torque up higher in the rev range that would utilise more fuel to chase it. That's why car tuners are in business... to unlock that potential using more aggressive timing and ecu tunes (with little/no regard to fuel consumption ).

I reckon the stock block will actually perform better at lower revs.... and consequently revving the crap out of it wont give you any performance increase (might even slow you down actually!). Peak torque is at 2800rpm. By 5000rpm I reckon it's dropped off quite a bit. Yeah power keeps rising until much later, but everyone should know by now that the sinking feeling you get in your seatback when you press the go pedal is TORQUE, not power. I reckon once you're in the early 4000's there would be noticeable drop in torque, and it would be more beneficial changing then- than trying to chase more power at the expense of torque further up the rev range to 5000 and beyond.

Someone give me an accurate dynograph (I dont care about the figures- which can vary greatly between different dynos anyway, just the actual graph itself showing Nm & Kw relative to rpm), and exact gear ratios (auto and manual). Best guesstimate right now though? Mid 4000's... no more.

Remember, the stock SV6 isnt an F1 race car. Higher revs with restrictive breathing and gentle tuning of a stock SV6= waste of fuel and no performance increase.

[Fekason]

I have the power and torque curves for the 3.0 and 3.6 SIDI engines within a pdf file.

Unfortunately I cannot download it to the forum at work, so will have to wait till I get home late tonight.

Torque rises from about 260 NM at 1.2K RPM to 295 NM at 2.0K, then the line steepens to 335 NM at 2.4K, levels out a bit to 350 at 2.9K and then remains between 330 and 340 NM until about 5.8K RPM.

The source of this data is a holden Product Information Sheet of September 2009.

[Fekason]

In addition, the above information is based on using 91RON fuel.

The same engine using higher octane fuel in the USA delivers 214.85 KW at 6.3K, and 364.50 NM at 3.4K. Maybe the Australian version would too, or the reduced figures in Oz could be set in the engine computer. I don't know the answer to that, though the Holden brochure does say slightly more power/torque might be available if using higher octane fuel.

[jamesmp]

you rekon its pretty safe then ? sometimes when i change into second it doesnt sit in and makes a crunching noise ? doesnt it just burn fuel to let it rev so high?

Two things - make sure you've timed the clutch release, gear change and accelerator squirt perfectly, but let the revs drop more before carrying out the aforementioned.

[UFO]

I have the power and torque curves for the 3.0 and 3.6 SIDI engines within a pdf file.

Unfortunately I cannot download it to the forum at work, so will have to wait till I get home late tonight.

Torque rises from about 260 NM at 1.2K RPM to 295 NM at 2.0K, then the line steepens to 335 NM at 2.4K, levels out a bit to 350 at 2.9K and then remains between 330 and 340 NM until about 5.8K RPM.

The source of this data is a holden Product Information Sheet of September 2009.

I'd be VERY interested to see these charts mate. They would be a terrific reference for those that own the SIDI engines here.
If you could post them it would be very much appreciated.