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I would take that 7.2 second 0-60 with a large grain of salt. Would not be the first time Pontiac has provided journalists with a car that was a "bit more than stock" - was just a few years ago that they finally admitted that the first two GTOs provided to testers in 1963 were a bit more than stock. Like 421s instead of 389s or the magic stop watch used for the "most famous 0-60" in 1965, 3.8 seconds, one road test that even Posche sidestepped years later.
 

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OTOH, 170 HP at 2860 (3110 running weight), and a working range of 170 ft-lb 4400RPM to 6400 RPM might actually do it. Mid-7 seconds, anyway.

Also depends on if they allow either an overrev to a properly geared second gear/final drive up to 60 mph, or set 2nd and final drive to avoid the 2-3 upshift at 55 mph (which can cost a 0-60 time of.... 0.22 seconds!!! :smile --- HEY, haven't I seen that time period somewhere before? :glol ), or just gear it to force the tester to upshift.

7.2 is probably a very agressive start with powershifts, or an optimistic article author, or a test from initial vehicle movement (which can vary by a tenth or two).

At the bottom of some of road and track's test sheets, it says something about their test procedures when accelerating using normal shifts, and not speed shifts, your actual 0-60 times may vary, blah,blah,blah.

I'd probably take it with a 0.22 grain of salt :wink and guess at 7.4 0-60 is probably more accurate.
 

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Just ran some quick calculations and with VVT I come up with 155 lb-ft at 2500 rpm, rising to 170 lb-ft at 4500, and then declining to 150 lb-ft at 6000 rpm. Redline not more than 6500, 98 mm (3.85") stroke is really pretty long to be spinning it that fast.

Personally, once you get over 3.5" stroke, I start thinking more torque than revs. but suppose the small bore makes for a light piston/rod assembly and with an undersqare engine it is easier to avoid detonation at high load/low revs such as a 2000 rpm 50 mph top gear pulling a hill.
 

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Ya, did same last night and got the 90% peak torque around 2200 (and around 154-156 at 2400 RPM, depending on how much retard/advance on cams - guessed at valve profile though). What, if any, software do you use (have some from MIT that aren't bad but complicated as s**t, and of course the old MIT 2-volume IC engine book for back of envelope, or several envelopes, calculation)?

Redline should be able to be spun to or more than 7000 rpm, but that's only my opinion.
 

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Examples from the 1960s of companies fudging on their 0-60 times? I know that to us this car is huge, but it isn't the make or break for them... and when you are talking about a car in the 7's... its not like the 0-60 time is make or break either. I see no reason for them to have tried to get around the true time. Not to mention if I recall, they were 75% and 85% complete, so they might change due to the changes still to come... so if the time increases I would be more likely to attribute it to that rather than them trying to work around it.
 

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Who cares if it's 7.2 or 7.4? Forced Induction from the dealership is the only way I'd buy a Solstice, and if a difference of .22 seconds actually matters to you then you probably don't want a slow 0-60 in 7.x seconds car anyway.
 

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skeptic said:
Who cares if it's 7.2 or 7.4? Forced Induction from the dealership is the only way I'd buy a Solstice, and if a difference of .22 seconds actually matters to you then you probably don't want a slow 0-60 in 7.x seconds car anyway.
:cheers :thumbs
 

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7.2 is not that optimistic, I had an 02 Z24 (dont laugh) with only an AEM Intake and a superturbo style muffler that would consistantly run 7.3-7.5 second 0-60 time and it was heavier and had less hp.
 

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DevlynSyde said:
skeptic said:
Who cares if it's 7.2 or 7.4? Forced Induction from the dealership is the only way I'd buy a Solstice, and if a difference of .22 seconds actually matters to you then you probably don't want a slow 0-60 in 7.x seconds car anyway.
:cheers :thumbs
:cheers :thumbs :smile

Point is, it's not an 8+ second car (like the base Miata!!!)
 

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The '65 test was more notable that the car was accompanied by Milt Schornak who had also performed some magic before the car was delivered.

Take the Autoweek cars (like in 64 there appear to have been two). The 2.4 RWD engine is not really in production yet so had to have been hand assembled. I would expect everything to be matched and then carefully run in on the dyno with a couple of engineers tuning in the "Powertrain Control Module" to "Stock Test #20" (maximum power) for the expected weather conditions (cool/damp) at Sea Level.

Maybe the head gaskets are a little thinner than what will be stock and the air filter element is removed or "special". Certainly in a 80% car, the exhaust system is not going to be expected to pass the EPA drive-by tests and no-one stuck a sniffer up the tailpipe.

Add some Mobil-1 oil for least drag at high rpm and the highest octane fuel they could find for no knock retard and you have something that is close to the max. It is just good marketting and they said specifically that this was not the way they were going to be sold. Heck they were probably 200 lbs lighter than the real thing as well, can think of several ways to arrange that.

So 7.2 second 0-60 is possible but I expect the "off the showroom floor" model to be a bit slower. Production tolerances and the ability to run on trash gas almost garentees it.

As to the rpm, I still think there will be a 6500 rpm redline on the tach (and maybe a telltale in the black box under the passenger seat mainly for warrenty reasons.

That 98 mm stroke is going to make for very high piston speeds and I doubt that the beancounters will allow it to be sold with anything more since it would need a lot of attention ($$$) to the bottom end and the oiling system not required for normal production engines to keep it alive.
 

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The 2.4 isn't a new-for-solstice engine. I would expect them to use an existing production engine running on pump gas for the test. As for the attention to the bottom end and oiling system used in production engines you might be interested in this, from http://www.saturnfans.com/Cars/Future/2.4lecotecfuture.shtml

Ecotec's Robust Design, Structure Enhanced for New 2.4-Liter Variant

Along with significant new technology additions, the new Ecotec 2.4-liter enjoys numerous upgrades to the robust basic Ecotec engine architecture. The Ecotec design, already noted for impressively low levels of noise and vibration, includes features like a structural oil pan; full-circle transmission mounting flange; a highly rigid lower crankcase with four-bolts at each bulkhead; long cylinder-head bolts to assure robust clamping of the cylinder head to the engine block; and direct-mounted accessories to eliminate these traditionally large contributors to engine noise, vibration and harshness.

The Ecotec 2.4-liter's basic structure has been enhanced in several significant ways to ensure the engine's increased displacement and power do not compromise the Ecotec's high levels of inherent refinement. "In the global engine family, we look at various engine components to evaluate which are the right 'fit' for any given engine application," said Subhedar. "Commonality is a vital part of the Ecotec program – it's like an interlocking puzzle. We try to choose the best combination of components from the myriad of available technologies.”

Thus the Ecotec 2.4-liter leverages several heavy-duty components and systems borrowed from the high-performance Ecotec supercharged 2.0-liter engine program, plus many that are unique to the new 2.4-liter variant:

* An auxiliary oil cooler that is approximately 30 percent smaller than similar-capacity oil coolers used on other engines.
* Piston-cooling oil jets spray the underside of each piston with a continuous bath of engine oil, increasing longevity by reducing engine operating temperatures.
* Redesigned cylinder head with structural improvements and new multi-layer steel gasket.
* New camshafts with optimized lobe profiles.
* Enhanced lubrication system to provide for the extra requirements of the camshaft phasers and piston-cooling jets, along with a deeper oil sump to handle the higher potential cornering forces.

The Ecotec 2.4-liter will be built at GM Powertrain's Spring Hill, Tennessee, assembly facility. The 2.4L Ecotec will be launched in the all-new 2005 Chevrolet Cobalt, and is reportedly slated for use in 2005 or 2006 model year Saturns.
 
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