rlchv70

There are lots of reasons to offer a turbo 4 over a V6:
Fuel economy
Weight
Cost

There also can be performance advantages of a turbo 4 over a NA V6. The turbo 4 would likely be much easier to crank up horsepower by just cranking up boost.

Most of GM's engines have not required 91 octane fuel. I would suspect that a theoretical turbo 4 would be the same.

jg95z28

Not only do I disagree, but your examples actually favor my argument, when you consider: GM's DI-V6 gets comparable fuel mileage to GM's turbo Ecotec especially when you have to run the turbo Ecotecs on 91 octane to get comparable HP. (Yes, we all know they run on 87, however while fuel mileage goes up, horsepower drops.); they weigh roughly the same (the LLT is only ~25-lb heavier than the LNF with inter-cooler); and the cost of maintaining a non-turbo engine vs. turbo over the life of the vehicle (100k mi?) is typically significantly less.

While I agree that the ability to simply "turn up the boost" makes the turbo Ecotec appear to give it an advantage over the DI-V6 in increasing performance, in the end run, there are plenty of things that can be done to boost the DI-V6's performance whereas the turbo Ecotec is already approaching the maximum of its performance potential.

AdioSS

In what vehicles have the turbo 4 and NA V6 both been offered in? That is the only way to really know how fuel economy compares between the 2.

90 Z28SS

You are substantially wrong with that comment , you would need to put a turbo on the 3.6 to even begin to hope to match whats capable with the stock LNF and KOA stock turbo . There are stock engine , stock turbo Cobalts making over 400lb/ft to the wheels , in addition, just a tune , 3" exhaust and air intake will push it well into the 300's to the wheels .On the subject of modding , your gonna retain alot more fuel economy on the turbo eco over the 3.6 . Even my lowly supercharged eco still would average in the 30's on the highway . If I were never to mod , I would probably prefer the na v6 if for anything it makes nicer sounds . I would much rather hot rod the ecotec though Im not saying the 3.6 isnt capable ( I dont know really as Ive never once seen anyone go beyond the basics and a couple scattered turbo systems ) ...Im sure if you start playing with ported heads , cam timing or custom cams and the general bolt ons your gonna find power sure , but its at such a disadvantage cost wise if you'd like to mod it . I dont know how strong the factory 3.6 shortblock is , I do know the ecotec is quite a strong piece and also has a boost friendly compression ratio , the 3.6 is rocking an 11.3:1 compression ratio .

IMO , the 3.6 is the tapped out factory combo unless you really wanna come of some serious cash to change that .

jg95z28

Just how streetable is that LNF setup, and will it pass smog?

HAZ-Matt

Probably. At part throttle it is practically the same as stock I bet.

90 Z28SS

Alot of those cars are daily drivers as in only cars . In normal driving , unless u have by preference a ridiculously loud exhaust , its really rather tame . Beauy of a turbo , stock cams and a OEM pcm and good strong foundation to get a lil wild with without worry It'd be a hell of alot more of a daily driver if u didnt have to worry about managing it in a FWD car I cant comment on emmisions , I live in a state that does not test The cobalt/sky/solstice/ion aftermarket community is so small in comparison to the mammoth f-body/stang/vette aftermarket , alot of the shops that are doing big things cant afford to emmissions test . I think Hahn might , but I honestly dont know . Whos to say a single turbo 3.6 with all the bolt ons and a healthy pcm tune would be emissions legal , I guess youd have to see such a combo first . V6 camaro guys are not getting to serious past exhaust and cia , tuning . Likely because there is hardly a 3.6 aftermarket beyond that .

Geoff Chadwick

Your point is taken, but moot. The 3.6L has a LOT of potential - but it requires modifications that void the warranty to do so, just as the LNF mods. GM doesn't care what can be done after or outside their warranty - they need an engine that will be dead-nuts reliable and cheap for them to repair and maintain during a warranty or lease period. In that regard, the 3.6L wins.
The header pipes are in a different spot than on the LS, but I see your point. The block width toward the journals and mains is not so different between them, but packaging is always difficult. Still, the LS is smaller - and every little bit helps.
For Cadillac, yes. In theory if someone decided to tweak the suspension design (for perhaps cost purposes or otherwise) it could have an effect (I know not how, I'm not a suspension guy). I hope that never happens though.

In a more serious note, we should have someone get some exterior dimensions for the 3.6L, the 6.2L, and the LNF. I'm curious how the three stack up in an engine bay. We know an LS block will fit into a Sky - but would an LNF fit into a C6?

teal98

Is 85 pounds reasonable for the added rigidity and larger brakes? That seems high to me, but it would make my arbitrary 100 pound number round instead.

teal98

Audi is showing what can be done with turbo 4s. There are almost no N/A V6s left in the Audi line, and I think we'll see a lot more of that in the future. Ford and Hyundai are also starting to replace V6s with turbo 4s. Buick too, for that matter. The manufacturers will not be able to afford to leave fuel mileage improvers like turbo direct injection on the table.

SSbaby

I'm glad you said that, Geoff, because now I can also post this...






Seems like a nice fit, hey?

krj-1168

A smaller & lighter 6th gen Camaro - may mean is smaller V6 motor as the base motor - but I highly doubt it will be a Turbo 4.

But then I also expect a smaller V8 for the SS model as well.

Z28x

I wouldn't be surprised if the 6th gen base motor was something like a non-turbo 2.4L 4cyl. making 200HP+

Z284ever

A smaller, lighter, 6th gen will mean alot of things. It certainly opens up alot more powertrain options. 4's and turbo 4's are DEFINITELY probable.

With that said, I also expect we'll see versions with full GenV smallblock fury under the hood.

Geoff Chadwick

And it's still an easier spark plug change than in a 4th gen fbody!
But if we're going to keep up this route, we might as well pull up the LS-to-RX7 swaps as well.

Now while GM couldn't realistically make an engine bay that small and stick an engine in there with all the modern trimmings (because of potential reliability, safety, NVH, and maintenance issues), the main reason the 5th gen engine bay is so big is because of styling and not much else - it could have been MUCH smaller if the vehicle was going for a different look.

Which is why I'm more interested in how a cadillac alpha comes to the table than how a Camaro alpha.