Should the Corvette abandon the V8 for an I6?

[dwightlooi]

Should the Corvette abandon the V8 for an I6? Or, maybe, its Camaro little brother should?

Although the Corvette is most identified with a V8 -- more specifically various iterations of the small block V8 -- it started life with an I6. Now that first Corvette wasn't very good, but fundamentally an Inline-6 is a smoother and more refined engine configuration than a V8. The I6 and H engines are the only ones with zero 1st and 2nd order vibrations. It also allows contemporary technology such as VVT phasers to be incorporated with half as many actuators as a V-layout because it has half as many camshafts. The I6 is also fundamentally stronger than a V8 because it has seven main bearings and does not use shared crankpins like V6 and V8 engines do. In many ways, 50/50 weight distribution and inline-6 refinement was what defined the BMW 3-series as the "Ultimate Driving Machine". The BMW M3 abandoned the I6 for a V8, maybe GM should pick up this configuration.

Maybe an engine configured as follows (derived from the Vortec 4200) should power the new Corvette, Impala and/or Camaro instead of the small block V8?

• 2010 3.9L "Blue Flame Six" I6 Turbo DI-VVT ( LIZ)
• Type: 3.9L I6 (LIZ)
• Fuel Injection: Direct gasoline injection
• Construction: Lost foam cast aluminum block and heads, forged steel crank and rods.
• Aspiration: Twin turbocharged and aftercooled; 1 x Honeywell-Garrett GT2554, 1 x Honeywell-Garrett GT2560 ball bearing turbochargers.
• Aftercooler: Front mounted aftercooler
• Compression ratio: 10.3:1 (13.2 psi maximum boost)
• Valve configuration: chain driven dual overhead camshafts (4 valves per cylinder)
• Valve lifters: roller finger followers with stationary hydraulic lash adjusters
• Firing order: 1 - 5 - 3 - 6 - 2 - 4
• Bore x stroke: 95.5 x 91 mm
• Fuel system: direct fuel injection
• Fuel type: Premium unleaded (91 Octane)
• Fuel shut off: 7000 rpm
• Horsepower: 508 hp ( 379 kW ) @ 6300-6800 rpm ( SAE CERTIFIED POWER )
• Torque: lb-ft. 432 lb-ft ( 585 Nm ) @ 2100-6100 rpm ( SAE CERTIFIED POWER )

• 2010 3.9L "Red Flame Six" I6 DI-VVT ( LIV)
• Type: 3.9L I6 (LIV)
• Fuel Injection: Direct gasoline injection
• Construction: Lost foam cast aluminum block and heads, forged steel crank and rods.
• Aspiration: Normally aspirated, w/six intake port mounted throttle butterflies.
• Compression ratio: 11.8:1
• Valve configuration: chain driven dual overhead camshafts (4 valves per cylinder)
• Valve lifters: roller finger followers with stationary hydraulic lash adjusters
• Firing order: 1 - 5 - 3 - 6 - 2 - 4
• Bore x stroke: 95.5 x 91 mm
• Fuel system: direct fuel injection
• Fuel type: Regular unleaded (87 Octane)
• Fuel shut off: 7000 rpm
• Horsepower: 362 hp ( 270 kW ) @ 6800 rpm ( SAE CERTIFIED POWER )
• Torque: lb-ft. 293 lb-ft ( 396 Nm ) @ 4800 rpm ( SAE CERTIFIED POWER )

[z28luvr01]

Just a word of caution - the last person that suggested that the Corvette be powered by anything other than a V8....well....isn't with us anymore.

j/k

It's a shame that the 4.2L will die with the GMT360s. I do like the idea of I6s being used in the Camaro (and other passenger cars), a lot.

[VenSeattle]

If GM were to introduce a sports car with an I6, it would be better to do so in an all-new vehicle, than try to change the image of an existing popular model. Saturn or possibly an all-new Pontiac probably be a good place.

[loki]

i think most every one would call blasphemy if it's used in a corvette... i could agree.

your red flame engine.... wouldn't the 6 butterfly valves do wierd things to vacuum? not saying it has to but just thought about it shortly.

power wise, those engines would be bad @#$ in the right vehicles

[dwightlooi]

i think most every one would call blasphemy if it's used in a corvette... i could agree.

your red flame engine.... wouldn't the 6 butterfly valves do wierd things to vacuum? not saying it has to but just thought about it shortly.

power wise, those engines would be bad @#$ in the right vehicles

The reason you want the throttle butterflies to be as close to the intake ports as possible is to minimize the air volume down stream of the throttle bodies and before the intake valves. This way you enhance throttle response since the time it takes for this volume to change pressurize/depressurize in response to throttle movements become very short. Just about every racing engine uses butterflies mounted on or near the intake ports. The E46 M3 engine and all the current V8 and V10 "M" engines use this arrangement.

Theoretically, it doesn't matter where you put the butterflies as long as it is after the filter and before the intake valves. In fact, if you can vary the intake valve lift continuously and with good response times you don't need butterflies. The amount of vaccuum you "see" in the take plumbing upstream of the butterflies will be less than down stream of it, but it'll still be proportional. You can either tap your vaccuum lines downstream of the throttle bodies in the intake port area or you can simply design the vaccuum actuated accessories to work at lower idle vaccuum levels. It shouldn't be a big deal.

[DetroitNut90]

If GM were to introduce a sports car with an I6, it would be better to do so in an all-new vehicle, than try to change the image of an existing popular model. Saturn or possibly an all-new Pontiac probably be a good place.

The Corvette has built a legacy off of offering authentic American V8 performance at a relative bargain. I wouldn't mess with that image.

It's a shame that the 4.2L will die with the GMT360s. I do like the idea of I6s being used in the Camaro (and other passenger cars), a lot.

The Atlas I6 is a wonderful engine, my parents test drove a Trailblazer LT while we were shopping for the Venture. I'd love to have a Zeta or Alpha with a nice I6.

[Nick]

The reason you want the throttle butterflies to be as close to the intake ports as possible is to minimize the air volume down stream of the throttle bodies and before the intake valves. This way you enhance throttle response since the time it takes for this volume to change pressurize/depressurize in response to throttle movements become very short. Just about every racing engine uses butterflies mounted on or near the intake ports. The E46 M3 engine and all the current V8 and V10 "M" engines use this arrangement.

Theoretically, it doesn't matter where you put the butterflies as long as it is after the filter and before the intake valves. In fact, if you can vary the intake valve lift continuously and with good response times you don't need butterflies. The amount of vaccuum you "see" in the take plumbing upstream of the butterflies will be less than down stream of it, but it'll still be proportional. You can either tap your vaccuum lines downstream of the throttle bodies in the intake port area or you can simply design the vaccuum actuated accessories to work at lower idle vaccuum levels. It shouldn't be a big deal.

I believe all new BMW engines utilize Valvetronic technologoy (infinitely variable valve lift similar to what you speak of at the beginning of your second paragraph). They don't even have throttle bodies (and I believe this goes the same for the new ///M engines...no more ITB's).

[dwightlooi]

I believe all new BMW engines utilize Valvetronic technologoy (infinitely variable valve lift similar to what you speak of at the beginning of your second paragraph). They don't even have throttle bodies (and I believe this goes the same for the new ///M engines...no more ITB's).

Actually... all the new BMW engines are valvetronic EXCEPT the "M" engines. The "M" engines do not use valvetronic because the infinitely variable valve lift system utilizing an intermediate swipe armature is incapable of supporting the high valve lifts the "M" engines demand and still be able to close sufficiently to support idle requirements. The "M" engines hence use traditional butterflies, albeit eight or ten of them mounted right on the intake ports and fed by trumpeted velocity stacks.

The "M" engines also do not use the magnesium-aluminum hybrid blocks. The new V8 and V10 "M" engines use an aluminum block whereas the E46 M3's 333hp 3.2 liter I6 used an IRON block.

Edited August 13, 2007 by dwightlooi

[Nick]

Actually... all the new BMW engines are valvetronic EXCEPT the "M" engines. The "M" engines do not use valvetronic because the infinitely variable valve lift system utilizing an intermediate swipe armature is incapable of supporting the high valve lifts the "M" engines demand and still be able to close sufficiently to support idle requirements. The "M" engines hence use traditional butterflies, albeit eight or ten of them mounted right on the intake ports and fed by trumpeted velocity stacks.

The "M" engines also do not use the magnesium-aluminum hybrid blocks. The new V8 and V10 "M" engines use an aluminum block whereas the E46 M3's 333hp 3.2 liter I6 used an IRON block.

Gotcha...yeah, I wasn't quite sure on the m engines...could've sworn the new v10 was valvetronic (which would make the v8 valvetronic) but I guess not. I suppose they still utilize double vanos?

The S54 was basically an evolution of the euro S50 which explains the iron block...those S-I6's are pretty heavy engines...one of the many reasons why LS engines are a popular swap in e36's...

Edited August 13, 2007 by Nick

[Camino LS6]

In Corvette or Camaro, no.

In something new, yes please.

[toesuf94]

I personally would love a BMW-esque I6 in the new base Camaro. They are smooth, efficient, and torquey as hell. As a personal luxo coupe competing in a price class just below a base 3 series and top of the line 1 series...what a car it would be.

In the Corvette - no. Simply...no. The Corvette has continued an upward performance trend since the 1956 came out...and (other than the late 70's early 80s) has not stopped that trend since. Performance and perception of the car has continued to grow since the ZR-1 and it appears to be reaching to new heights with the '08/09 model years. I think the I-6 would be a slap in the face to those of us who have supported the Corvette all of these years and have driven it to the car it is now - a world class sports car at a bargain price ( Although, $71,000 for an LT3 Convertible is starting to get out of 'bargain' territory. )

[91z4me]

I personally would love a BMW-esque I6 in the new base Camaro. They are smooth, efficient, and torquey as hell.

They are also harder to package than a traditional V style engine. Something that people can easily forget.

Not to mention that there would have to be additional funding (besides the 3.6 HF family's) to create this little engine.

[CaddyXLR-V]

That would be a better engine for the Cadillac CTS, or an Alpha Pontiac/Cadillac. Since we are just dreaming anyway, I wouldn't mind it in the Pontiac's mid-engine version of the Corvette.

[Sixty8panther]

Oh boy, you have gone and opened up a can of worms...

About 2 years ago I started a thread abot how the Camaro

(when it comes back) should be powered by a INLINE-SIX

based off the Atlas in the Chevrolet Trailblazer (just make

a more shallow oil pan) and I suggested there be a TURBO

package that would position the Camaro where the Skyline

GT-R (R34) used to be... near exotic.

I wonder if Fly would be so kind as to link it off the old forum. :smile:

[Camino LS6]

My reservations about the Camaro are mostly packaging concerns (which eliminate it for the Corvette as well).

But, the notion of a mid-engined Pontiac sporting this powerplant - Wow!

It's too damn late to be giving me ideas like that, Mr Caddy! :AH-HA_wink:

[AxelTheRed]

Putting a 6 of any kind into the Corvette would only hurt the image of the car.

[Z-06]

Pontiac Midengine car is a good idea for a performance brand. But as P_C_S said Pontiac is Tick Tock so it won't work.

[Camino LS6]

Pontiac Midengine car is a good idea for a performance brand. But as P_C_S said Pontiac is Tick Tock so it won't work.

I think not.

[ocnblu]

Pontiac Custom-S has been brainwashed by the evildoers at Opel. We must remember that when we read his posts. He's an ok guy otherwise, if we can look past that kink.

[K.C.]

A Corvette with a 6 cylinder engine? Thats unAmerican. Shame on you!

[dwightlooi]

A Corvette with a 6 cylinder engine? Thats unAmerican. Shame on you!

The First Corvette had an Inline-6 :AH-HA_wink:

[CaddyXLR-V]

The First Corvette had an Inline-6 :AH-HA_wink:

And GM switched away from that idea real quick :AH-HA_wink:

The I6s you described sound like great engines, but I don't think they belong in a Corvette.

I'll take one in a Saturn Sky though, if it fits.