LY7 3.6 L DOHC Dual-VVT

[thegriffon]

How much does GM underestimate engine power? We all know GM is notoriously conservative when calculating engine power. This has been highlighted the last couple of years as GM has begun a comprehensive program of third-party certification, with nominal horsepower increases even as rival automakers cut power claims with the advent of the new SAE standard. The latest beneficiary is the new higher-output version of the fwd LY7 in the Acadia and Outlook crossovers. Compare the previously published figures with the latest, certified results. Ford and Toyota, read'em and weep.

Power (hp / kW)

263 / 196 @ 6600 rpm w/ single exhaust (est.)

270 / 201 @ 6600 rpm w/ single exhaust (cert.)

267 / 199 @ 6600 rpm w/ dual exhaust (est.)

275 / 205 @ 6600 rpm w/ dual exhaust (cert.)

Torque (lb-ft / Nm)

244 / 331 @ 3200 rpm w/ single exhaust (est.)

248 / 336 @ 3200 rpm w/ single exhaust (cert.)

247 / 335 @ 3200 rpm w/ dual exhaust (est.)

251 / 340 @ 3200 rpm w/ dual exhaust (cert.)

We can only guess at how much GM has under-rated earlier, uncertified versions of the LY7.

[Flybrian]

Yes, I noticed that on some the dealer order guides. That's even better and, well, amazing.

[Northstar]

That's pretty impressive to say the least. If you add 15% to those figures (I believe that's what the GM press release said DI would add) you get over 315HP.

[ZL-1]

Better to under-rate them and have it certified with higher hp/tq than the other way around

It's good PR

[loki]

looking good, and even better for the cady's in the next year.

[goblue1999]

Better to under-rate them and have it certified with higher hp/tq than the other way around

It's good PR

187341[/snapback]

The japs don't think so....they would rather advertise them high, to get the press and sales traffic, and then hope nobody notices when they come in low, since they have a full time apologist staff working in the automotive press.

[Dsuupr]

WOW, that's a lot of power for those SUVs. I wonder if how much that also changes the Saturn Aura ratings.

[prototype66]

I guess my question would be what is the real mpg going to be.HP is sweet as long as you get the most out of the tankfull. I know alot has to do with the gearing as well so does anyone have any data on the numbers yet,or is it too early on?

[ZL-1]

The japs don't think so....they would rather advertise them high, to get the press and sales traffic, and then hope nobody notices when they come in low, since they have a full time apologist staff working in the automotive press.

187794[/snapback]

I thought those lower ratings were a result of changing to the new SAE rating system and not a 'projected-/expected-hp vs. certified-hp' situation.

[boblutzfan]

I guess my question would be what is the real mpg going to be.HP is sweet as long as you get the most out of the tankfull. I know alot has to do with the gearing as well so does anyone have any data on the numbers yet,or is it too early on?

187803[/snapback]

I love the Malibu Man signature...

[mikehamm45]

With the old OHV engines, GM used to have so much more torque.

The HP ratings with these engines is impressive, but I would rather see the torque closer to 300.

[Northstar]

With the old OHV engines, GM used to have so much more torque.

The HP ratings with these engines is impressive, but I would rather see the torque closer to 300.

187823[/snapback]

Not really. The OHV engines just made more torque than HP because they made such a lousy amount of HP. The only thing that made great torque was the supercharged 3800.

For example, look at the larger 3.9L OHV V6 from the Impala: only 240 lb-ft, while these 3.6L DOHC engines are making around 250lb-ft with less displacement.

[boblutzfan]

Not really. The OHV engines just made more torque than HP because they made such a lousy amount of HP. The only thing that made great torque was the supercharged 3800.

For example, look at the larger 3.9L OHV V6 from the Impala: only 240 lb-ft, while these 3.6L DOHC engines are making around 250lb-ft with less displacement.

187824[/snapback]

The advantage of the OHV engines was that a large percentage of the torque was available low in the RPM range. Do you know where the torque numbers match up on these two engines in terms of RPM?

BTW - these engines look great.

[Northstar]

Dyno sheets:

3.9:

http://media.gm.com/us/powertrain/en/produ..._LZ8_Impala.pdf

3.6

http://media.gm.com/us/powertrain/en/produ..._LY7_Acadia.pdf

The 3.6 makes more torque at basically all RPMs... in addition it never has less than 200 lb-ft while the 3.9 does dip below 200 for a little while.

[cletus8269]

are they going to use that for the base camaro? v6 numbers havent been that nice in my eyes since the Buick GN's were running down 5.0's

[LTB51]

I thought those lower ratings were a result of changing to the new SAE rating system and not a 'projected-/expected-hp vs. certified-hp' situation.

187812[/snapback]

That is true. And if you notice, Toyota/Honda re-rated all their existing engines instead of waiting until the next model year.

That was a big mistake.

Take, for example, the 2.4 engine in the Accord. It was rated at 160 pre-SAE J1349, then down to 155(?) on J1349, and the next model year it was 166 J1349.

Similarly, the TSX went 200 -> 195(?) ->204

If they had just done what some manufacturers are doing (no names ), and just rated new vehicles, the accord would have gone from 160-> 166 and the TSX from 200 to 2004. Look at how Honda underrates their engines! Just imagine what all their previous engines "really put out"!

Don't get me wrong, I'm a big fan about leveling the playing surfaces when testing. But what is impressive about this switch is the politics that GM played, not the change in the engine HP.

[BlkHhr104]

The Acura TL went from 270 to 258 too.

[ZL-1]

That is true.  And if you notice, Toyota/Honda re-rated all their existing engines instead of waiting until the next model year. 

That was a big mistake. 

Take, for example, the 2.4 engine in the Accord.  It was rated at 160 pre-SAE J1349, then down to 155(?) on J1349, and the next model year it was 166 J1349.

Similarly, the TSX went 200 -> 195(?) ->204

If they had just done what some manufacturers are doing (no names  ), and just rated new vehicles, the accord would have gone from 160-> 166 and the TSX from 200 to 2004.  Look at how Honda underrates their engines!  Just imagine what all their previous engines "really put out"!

Don't get me wrong, I'm a big fan about leveling the playing surfaces when testing.  But what is impressive about this switch is the politics that GM played, not the change in the engine HP.

187910[/snapback]

I agree with you. 100%.

It's just a smart way to generate good PR.

Edited September 1, 2006 by ZL-1

[regfootball]

With the old OHV engines, GM used to have so much more torque.

The HP ratings with these engines is impressive, but I would rather see the torque closer to 300.

187823[/snapback]

they still out torque the pushrods.

[regfootball]

fly, the ford's not that far behind. especially considering its 3% short in displacement and i think the ford only has vvt on one side.

It's fair to say both engines are comparable.

What is nice to think about, is both the GM and Ford mills getitng direct injection eventually.

It's fair to say that Ford and Gm finally listened, that folks want better v6's. Now they just need to make more of them and get them into more cars.

[loki]

will this be a sign of things to come in aura g6 lacrosse and malibu? i'm guessing malibu for 08 could have a ~265hp version, and the others getting the 270hp? or will these revised engines be in short demand causing the EPs to keep thier current lineup till... 2010?

[thegriffon]

I thought those lower ratings were a result of changing to the new SAE rating system and not a 'projected-/expected-hp vs. certified-hp' situation.

187812[/snapback]

Indirectly. In most circumstances the Japanese were incorrectly quoting Japanese figures rather than tests using any SAE standard at all (old or new). The introduction of the new SAE standard prompted new testing which highlighted the discrepancy. US automakers had been conservative in implementing the old SAE test, and had a larger hand in writing the new one (i.e. it now reflects more closely the setup GM has always used to test its engines). Third-party certification eliminates a certain amount of additional losses that GM had factored in, but not strictly required, resuting in higher results. Most companies have waited for new, higher-output engines before introducing the new standard. There are still some highly suspicious results quoted from some automakers. Honda for one quotes the same figures, irrespective of units (metric or US hp) or standard (JIS, EEC or SAE) for the new R18A 1.8 L in the new Civic, when there should be different results for each (SAE the lowest, not as it is at the moment, the highest).

[Mike The Canadian]

I like the power and all...but 6600 rpms...

oh well... i'm used to driving a car thats rarely reved over 4000

What worries me about these is the mileage....

gm has good ohv v8's, and crappy v6's of every type....

the 2.8 and 3.6 were rated practically the same on the cts...pretty ridiculous

[DetroitNut90]

Cool-more power is always good.

The 3.6 has impressed me since its launch.

[GMman]

Somebody tell Bob to get the 3.6 in the Lucerne....now!!

[mjd1001]

WOW, that's a lot of power for those SUVs.  I wonder if how much that also changes the Saturn Aura ratings.

187798[/snapback]

Actually, it's not a lot of power for those SUV's, when you consider those SUV's are going to weigh almost 5,000 lbs.

Power to weight ratio, that puts them below the Escalade, Tahoe, Yukon, Rav4, V6 powered Vue, Trailblazer/Envoy...and maybe a few more also.

[FUTURE_OF_GM]

The japs don't think so....they would rather advertise them high, to get the press and sales traffic, and then hope nobody notices when they come in low, since they have a full time apologist staff working in the automotive press.

187794[/snapback]

LMFAO!!!!

Agreed.... And I think that it is utterly stupid for GM to underrate their HP numbers. Nobody cares enough to find out the truth, if they did this kind of thing would be common knowledge. The average car buyer goes by what the manual says (If they even have a clue in the first place) and they could care less if GM, IN GOOD WILL, OVER delivered on the promise. In fact, they'd probably be skeptical to believe it if they heard it.

So, that said, GM should EXPLOIT the hell out of the actual numbers.... It's extrememly DUMB in this "horsepower driven" (Yeah right, you're average import yuppie doesn't even know what the hell the term means) race to HANDICAPP yourself right out of the gate. But, of course, GM is good at shooting themselves in the foot.

[carman21]

The FWD 3.6L V-6 is now rated at 20/28 with a 6spd Auto. That is a big jump. from the LaCrosse's 18/27. Dual-VVT makes all the difference.

Original 3.6L V-6

240-270hp

18/27 MPG

Upgrade with Dual VVT

240-270hp(appox)

20/28 MPG

Upgrade with Direct Fuel Injection

288-324hp

22/31MPG

The FWD applications will range from 288-306hp with ft/lb torque levels from the 260s to the 280s. Excellent news!

[thegriffon]

Supposedly the fwd 3.6 has always had dual-VVT. The single, intake VVT version has a different RPO, LE0 rather than LY7, and until recently produced even less power (just 210-230 hp) than in the LaCrosse (due to different standards it still may).

[loki]

The FWD 3.6L V-6 is now rated at 20/28 with a 6spd Auto. That is a big jump. from the LaCrosse's 18/27. Dual-VVT makes all the difference.

Original 3.6L V-6

240-270hp

18/27 MPG

Upgrade with Dual VVT

240-270hp(appox)

20/28 MPG

Upgrade with Direct Fuel Injection

288-324hp

22/31MPG

The FWD applications will range from 288-306hp with ft/lb torque levels from the 260s to the 280s. Excellent news!

189021[/snapback]

have to remember that's a 4speed vs a 6 speed though too.

DI , i'd say it goes up to 21/29 max, not 22 / 31......

[carman21]

The 20/28MPG figure was produced partially by the 6spd auto however, Toyota recieved similar numbers with its 5spd coupled to the 3.3L V-6. The Toyota 3.5L V-6 gets 22/31. So, I believe Direct Injection will allow GM's 3.6L V-6 to see similar numbers to Toyota's 3.5L V-6, perhaps better since GM will use a more advanced six sped auto than the Avalon's 5spd auto.

My point is GM is rapidly catching up. Add AFM to the DI 3.6L V-6 and we may see big jump in MPG. For Instance, the 5.3L V-8 used in the Impala gets 20% better MPG than the non-AFM 5.3L V-8.

5.3L V-8

Without AFM

16/22

With AFM

18/28

The 6.0L 400hp V-8 on the Camaro concept with AFM gets 30MPG hwy that is a 50% yeild over the non-AFM 6.0L V-8. I can't wait until AFM gets added to the hosts of technologies already in GM's DOHC Engines

[bcs296]

Actually, it's not a lot of power for those SUV's, when you consider those SUV's are going to weigh almost 5,000 lbs.

Power to weight ratio, that puts them below the Escalade, Tahoe, Yukon, Rav4, V6 powered Vue, Trailblazer/Envoy...and maybe a few more also.

188107[/snapback]

Good to see I'm not the only one who realizes how overwhelmed these new engines are going to be when in the Lambdas.

[Aura XR]

Makes me wonder how much HP my XR makes?

When the car was first being revealed, it was claimed to be 270, now it is down to 252. I wonder if that is an underestimate.