GM Confirms 420 HP 3.6L LF3 Twin Turbocharged V6 for 2014 CTS

[shaffe]

Originally Posted by Angrybird 12

I think there is a certain negative view towards V8 engines, even those that get nearly the same fuel economy and power that a twin turbo V6 does. Just look at the Ecoboost V6 in the ford trucks. Even though the power and economy of it is close to the base V8 available but costing more money they can't seem to make enough of the Ecoboost engined trucks. The Ecoboost v6 has 5 more HP and 40 ftlbs of torque more than the 5.0 V8. But it only gets 1 mpg more than the V8.
Then it costs about $1K more than the V8.

Is it really worth it? I still think its mostly public perception that V8's are bad and V6's are good.

All depends on who you talk to it seems with the Eco-Boost F-150s.

General consensus from people I know with them is that it is a fantastic engine. The torque is plentiful from low RPMs which all of them love.

as far as the MPGs that kind of seems to be a wide range of opinions on it. Some of the guys I know with them, get great gas mileage and others get terrible. Seems to really depend on how you drive it.

I cant wait to see what this engine in the CTS does performance wise.

[Kyle2k]

Does this engine have a heat exchanger like a supercharger then?

[GretchenGotGrowl]

Originally Posted by Kyle2k

Does this engine have a heat exchanger like a supercharger then?

yes, the charge pipes have a built-in heat exchanger similar to what the LS9 uses.

[Mr. Wyndham]

Originally Posted by Kyle2k

Does this engine have a heat exchanger like a supercharger then?

Check this action out - it's a REALLY tight package. And the article references how powertrain engineers really like the heat exchanger system they tried with the LS9 & LSA.

http://bcove.me/wnyly06c

The coolest part (IMO) is that with the removal of the exhaust manifolds, the direct-mounting of the turbos to the engine block (essentially taking the place of the manifolds), and the short path (therefore less tubing) to the throttle...I'm not sure this thing will weigh a whole ton more than a standard V6.

[Kyle2k]

Originally Posted by Mr. Wyndham

Check this action out - it's a REALLY tight package. And the article references how powertrain engineers really like the heat exchanger system they tried with the LS9 & LSA.

http://bcove.me/wnyly06c

The coolest part (IMO) is that with the removal of the exhaust manifolds, the direct-mounting of the turbos to the engine block (essentially taking the place of the manifolds), and the short path (therefore less tubing) to the throttle...I'm not sure this thing will weigh a whole ton more than a standard V6.

The throttle body is internal too- this is so weird and cool lol!

[Stew]

I like the idea of an AWD XTS with this in it.

[Mr. Wyndham]

Originally Posted by Mr. Wyndham

Check this action out - it's a REALLY tight package. And the article references how powertrain engineers really like the heat exchanger system they tried with the LS9 & LSA.

http://bcove.me/wnyly06c

The coolest part (IMO) is that with the removal of the exhaust manifolds, the direct-mounting of the turbos to the engine block (essentially taking the place of the manifolds), and the short path (therefore less tubing) to the throttle...I'm not sure this thing will weigh a whole ton more than a standard V6.

I was very interested in this concept from the first rumor years ago.....but if you had told me I'd be drooling over a V6, I'd have told you you were insane.

Hell...if you'd have said that the TTV6 would have 420/430 tq...I'd have called you nuts...I thought 400 would be a stretch And.....I think those are estimates, right? Could be as awesome as 430/440?

[GretchenGotGrowl]

Originally Posted by Mr. Wyndham

I was very interested in this concept from the first rumor years ago.....but if you had told me I'd be drooling over a V6, I'd have told you you were insane.

Hell...if you'd have said that the TTV6 would have 420/430 tq...I'd have called you nuts...I thought 400 would be a stretch And.....I think those are estimates, right? Could be as awesome as 430/440?

I don't see why it can't go quite a bit further than that. We have several Supercharged LLTs running those HP levels without issue and the LFX is a lot more FI-friendly. Lowering the compression ratio to 10.2:1 should allow it to run quite a bit more boost, and it sounds like the beefed up the rods (which are already very tough) and the pistons (which we've seen some breakage on in the LLTs). I bet the tuners will have these things running around 600 BHP in no time. I would think GM is just being a bit conservative and leaving something on the plate if they get some competiton from Ford.

[Kyle2k]

Originally Posted by GretchenGotGrowl

I don't see why it can't go quite a bit further than that. We have several Supercharged LLTs running those HP levels without issue and the LFX is a lot more FI-friendly. Lowering the compression ratio to 10.2:1 should allow it to run quite a bit more boost, and it sounds like the beefed up the rods (which are already very tough) and the pistons (which we've seen some breakage on in the LLTs). I bet the tuners will have these things running around 600 BHP in no time. I would think GM is just being a bit conservative and leaving something on the plate if they get some competiton from Ford.

How is fueling for the LLT, anyone running out of injector?

[GretchenGotGrowl]

Originally Posted by Kyle2k

How is fueling for the LLT, anyone running out of injector?

Injectors haven't been a problem so far. The HPFP (high-pressure fuel pump) in the LLT seems to max out around 550 BHP and on the LFX at around 660 BHP. I would imagine they have a different version of the HPFP in the LF3. I'm sure the injectors will become a problem at some point, but we are not having an issue with them keeping up on my LFX.

[KKreme15]

This new motor has me like

[big hammer]

Originally Posted by GretchenGotGrowl

We don't have the SAE certified numbers for the LT1 yet, so we can't really compare. I can tell you from experience, having TQ that comes on instantly like a TT engine and maintains most of that TQ all the way put to 5500 RPM is completely different that an engine that peaks early and drops off quickly. It remains to be seen what the power curves look like for both engines, but it appeals to people like me.

the new LT1 engine actually has an extremely flat torque curve for an n\a engine. these aren't your 1999 5.3's anymore.

[GretchenGotGrowl]

Originally Posted by big hammer

the new LT1 engine actually has an extremely flat torque curve for an n\a engine. these aren't your 1999 5.3's anymore.

I agree the DI and VVT help a lot. But add turbos to the lot and it extends that torque curve even more. This is especially true when you go with small turbos like what is described in the article.

[truth411]

Originally Posted by GretchenGotGrowl

I agree the DI and VVT help a lot. But add turbos to the lot and it extends that torque curve even more. This is especially true when you go with small turbos like what is described in the article.

But i bet $100 the LT1 would produce more torque everywhere in the powerband. While at the same time being more powerful, equal or more fuel efficient and more profitable. This ne ttv6 sounds exspensive. I still say an LT1 makes more sense for an ATSV. Imvho.