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Javelin
Javelin MegaDork
10/24/12 12:32 p.m.

In reply to 92CelicaHalfTrac:

Yup, even over the Euros. Ferrari tried to say the 458's V8 had a higher specific, then GM stomped them. The new 13 Shelby GT500 might have the overall "highest HP total" number IIRC, but that won't last long at all.

There's a reason everyone and their great aunt Lucie is swapping the damn things.

tuna55
tuna55 UberDork
10/24/12 12:32 p.m.
Bobzilla wrote:
tuna55 wrote:
Bobzilla wrote: Now... give me that engine in the 4.8L displacement with the short stroke/big bore combo, shove it into the new Caprice and give it 3 pedals with 6 forward gears, and LSD and I'll be the first motherberkeleyer in line to buy it.

Why would you want less displacement?

even with the smaller displacement it would still be 350hp, but less cubes to feed would be more highway economy.

That and the 4.8 loves to rev.

Ughh.. I consider that a myth fed by poor quality parts available in the 60's leading folks to destroke engines. I don't really think it has any merit these days.

You may be right about mileage, but I suspect the gain would be fairly minimal. Your frictional losses are much the same and the injector can be controlled much better now to provide 25 hp at cruise, so 25 hp will still require roughly the same amount of fuel given the same engine architecture.

Gearheadotaku
Gearheadotaku SuperDork
10/24/12 12:33 p.m.
dculberson wrote: I would have thought that direct injection and all the other fanciness would be good for more than 20hp. (the LS3 is 430hp, the LT1 is 450hp, same displacement.) Still, sweet motor and proof this is a great time to be a gearhead.

it's all about emissions and gas mileage.....

tuna55
tuna55 UberDork
10/24/12 12:35 p.m.
yamaha wrote:
tuna55 wrote:
wvumtnbkr wrote: For one, it would make the engine larger. Those cams have to go somewhere. There was actually a pretty good thread about exactly this topic a few weeks ago. If you search for OHC, you will probably find it. Rob

the ZR1 C4 was exactly that experiment. The pushrodded motor could manage a much larger displacement for the same engine size, so no net sacrifice of power per pound, power per dimension, power per fuel. In other words, to manage the same hp figure, the OHC cam engine GM would hypothetically design would be heavier, bigger but have less cubic inches of displacement.

However, those ZR1's woke up much faster than the comparable tpi once lingenfelter got ahold of them. The LT5 was honestly better than the lt-1. I like the lt5 cars......I really do. I like the lsx cars as well, the experiment produced a great engine that should have been continued.

Oh I agree that the LT1 is inferior to the LT5. No doubt. That's not the experiment. They essentially short shifted engine development. They wanted to know if the LS1 should iterate upon the LT1 design theme or if it should depart through the path blazed by the LT5. The result of this experiment was the LS1 we know and love today. Had the LT5 been better, cheaper, smaller, whatever, the resulting LS1 would have bettered that technology instead.

"Corvette from the Inside", written by the chief engineer in that era, Dave McLellan, provides a lot of these insights.

92CelicaHalfTrac
92CelicaHalfTrac MegaDork
10/24/12 12:37 p.m.
Javelin wrote: In reply to 92CelicaHalfTrac: Yup, even over the Euros. Ferrari tried to say the 458's V8 had a higher specific, then GM stomped them. The new 13 Shelby GT500 might have the overall "highest HP total" number IIRC, but that won't last long at all. There's a reason everyone and their great aunt Lucie is swapping the damn things.

The LS9 trumps the Audi 4.2... barely. Not exactly an apples to apples comparison, though.

Other than that... i'm not seeing any other LS motor that the Audi 4.2 doesn't beat out in terms of HP/L. (98.6.)

Javelin
Javelin MegaDork
10/24/12 12:38 p.m.

In reply to 92CelicaHalfTrac:

It only takes one, now stop ricer mathing.

yamaha
yamaha Dork
10/24/12 12:42 p.m.
tuna55 wrote:
Bobzilla wrote:
tuna55 wrote:
Bobzilla wrote: Now... give me that engine in the 4.8L displacement with the short stroke/big bore combo, shove it into the new Caprice and give it 3 pedals with 6 forward gears, and LSD and I'll be the first motherberkeleyer in line to buy it.

Why would you want less displacement?

even with the smaller displacement it would still be 350hp, but less cubes to feed would be more highway economy.

That and the 4.8 loves to rev.

Ughh.. I consider that a myth fed by poor quality parts available in the 60's leading folks to destroke engines. I don't really think it has any merit these days.

You may be right about mileage, but I suspect the gain would be fairly minimal. Your frictional losses are much the same and the injector can be controlled much better now to provide 25 hp at cruise, so 25 hp will still require roughly the same amount of fuel given the same engine architecture.

Not from todays experience, but the theory was back then......a 383 stroker(350block/400crank) would have a lower redline due to rotational forces as opposed to the 377destroker(400block/350crank) which was smoother and would live nearly all day at 8k.....

With modern technology, you would figure that this has been solved, but I still suspect that the longer stroke engines can't rev as high reliably.

93EXCivic
93EXCivic MegaDork
10/24/12 12:44 p.m.

In reply to Javelin:

Caparo T1 has a 3.5litre pumping out 575bhp or the Radical 2.8 litre with 455bhp.

volvoclearinghouse
volvoclearinghouse Reader
10/24/12 12:44 p.m.
dculberson wrote: I would have thought that direct injection and all the other fanciness would be good for more than 20hp. (the LS3 is 430hp, the LT1 is 450hp, same displacement.) Still, sweet motor and proof this is a great time to be a gearhead.

Probably has something to do with the Twin E's: Efficiency and Economy. The new engine has to meet stricter requirements for both. To do that, and make equal or better HP/TQ numbers is a feat of engineering.

92CelicaHalfTrac
92CelicaHalfTrac MegaDork
10/24/12 12:46 p.m.
Javelin wrote: In reply to 92CelicaHalfTrac: It only takes one, now stop ricer mathing.

Sorry buddy... when you post stuff like this:

Javelin said: The GM LS family has had the highest specific outputs (HP/L) and actual ouputs of any V8 for the last ~10 or so years for a reason...

There's going to be discussion about it.

Ricer math tells me that the statement isn't correct. 2008 in particular jumped out pretty quickly.

No need to get E36 M3ty or prickly over it, it's just a discussion.

tuna55
tuna55 UberDork
10/24/12 12:49 p.m.
volvoclearinghouse wrote:
dculberson wrote: I would have thought that direct injection and all the other fanciness would be good for more than 20hp. (the LS3 is 430hp, the LT1 is 450hp, same displacement.) Still, sweet motor and proof this is a great time to be a gearhead.

Probably has something to do with the Twin E's: Efficiency and Economy. The new engine has to meet stricter requirements for both. To do that, and make equal or better HP/TQ numbers is a feat of engineering.

Hear hear!

Man, wished we lived closer. We could discuss this some time over a beer.

nocones
nocones Dork
10/24/12 12:50 p.m.
Javelin wrote: The GM LS family has had the highest specific outputs (HP/L) and actual ouputs of any V8 for the last ~10 or so years for a reason...

Mclaren MP12-4C 592Hp/3.8L = 155HP/L FI
Ferrari 458 562HP/4.5L = 124HP/L NA
LS9 638HP/6.2L = 102HP/L FI

Am I misunderstanding your claims? Don't get me wrong obviously these engines are in a different cost bracket, but the Mclaren produces 50% more HP per liter.

volvoclearinghouse
volvoclearinghouse Reader
10/24/12 12:52 p.m.
tuna55 wrote:
volvoclearinghouse wrote:
dculberson wrote: I would have thought that direct injection and all the other fanciness would be good for more than 20hp. (the LS3 is 430hp, the LT1 is 450hp, same displacement.) Still, sweet motor and proof this is a great time to be a gearhead.

Probably has something to do with the Twin E's: Efficiency and Economy. The new engine has to meet stricter requirements for both. To do that, and make equal or better HP/TQ numbers is a feat of engineering.

Hear hear!

Man, wished we lived closer. We could discuss this some time over a beer.

Yes, and I could explain to you the vast advantages of using torsion springs over coil springs. And why NASCAR should have been using them for the past 150 years.

carguy123
carguy123 PowerDork
10/24/12 12:54 p.m.

As far as why only 20 hp? You are only looking at the peak number. I'm betting this creates more power across the band due to all the new E&E governmental requirements for new cars.

93EXCivic
93EXCivic MegaDork
10/24/12 12:55 p.m.
nocones wrote:
Javelin wrote: The GM LS family has had the highest specific outputs (HP/L) and actual ouputs of any V8 for the last ~10 or so years for a reason...

Mclaren MP12-4C 592Hp/3.8L = 155HP/L FI
Ferrari 458 562HP/4.5L = 124HP/L NA
LS9 638HP/6.2L = 102HP/L FI

Am I misunderstanding your claims? Don't get me wrong obviously these engines are in a different cost bracket, but the Mclaren produces 50% more HP per liter.

Also Radical SR9 LM 455bhp/2.8L= 162.8 HP/L
Caparo T1 575hp/3.5L= 164.3HP/L
GT500 662hp/ 5.4L= 122.6HP/L

yamaha
yamaha Dork
10/24/12 12:55 p.m.

So we'll leave out the 5.4L making 600+ in the '13 gt500?

GameboyRMH
GameboyRMH PowerDork
10/24/12 12:57 p.m.
Ranger50 wrote: Looks like EPAS is coming too, note no PS pump and belt. But it does look like the balancer is fitted for a 8 or 10 rib belt. Hello supercharger?

Could that thing that looks like a huge idler wheel not be a PS pump? I think I see two hose fittings on the back.

The presentation says e-throttle will be standard on this engine, hopefully they won't take the opportunity to muck it up.

Looks good but the big appeal of the LSx is cheapness, and this won't be cheap for a while.

Javelin
Javelin MegaDork
10/24/12 12:57 p.m.
93EXCivic wrote: In reply to Javelin: Caparo T1 has a 3.5litre pumping out 575bhp or the Radical 2.8 litre with 455bhp.

Neither of which is a production engine, but I digress. I'm just loosely quoting some GM commercials from last year, I don't actually care.

Back to the LT1's new hotness...

Flight Service
Flight Service UltraDork
10/24/12 1:00 p.m.
singleslammer wrote:

More like Cha-Ching!!! VVT and DI are not cheap add ons.

yamaha
yamaha Dork
10/24/12 1:01 p.m.
93EXCivic wrote:
Javelin wrote: The GM LS family has had the highest specific outputs (HP/L) and actual ouputs of any V8 for the last ~10 or so years for a reason...

GT500 662hp/ 5.4L= 122.6HP/L

nvm.....damn posting while I type.

AutoXR
AutoXR HalfDork
10/24/12 1:40 p.m.

Supposed to be a 5.5L according my my old colleagues @ GM Canada

Bobzilla
Bobzilla UltraDork
10/24/12 1:48 p.m.
GameboyRMH wrote:
Ranger50 wrote: Looks like EPAS is coming too, note no PS pump and belt. But it does look like the balancer is fitted for a 8 or 10 rib belt. Hello supercharger?

Could that thing that looks like a huge idler wheel not be a PS pump? I think I see two hose fittings on the back.

The presentation says e-throttle will be standard on this engine, hopefully they won't take the opportunity to muck it up.

Looks good but the big appeal of the LSx is cheapness, and this won't be cheap for a while.

GM's been using TBW since 2003 on all the V8's.

Javelin
Javelin MegaDork
10/24/12 1:58 p.m.
AutoXR wrote: Supposed to be a 5.5L according my my old colleagues @ GM Canada

GM just said this won't happen, in the Vette anyway, as the cylinder-deactivation then didn't work so hot. Wouldn't be surprised to see a non-AFM 5.5 in the trucks though.

Javelin
Javelin MegaDork
10/24/12 1:59 p.m.
Bobzilla wrote: GM's been using TBW since 2003 on all the V8's.

Nope. 2004 GTO was cable-driven.

That said, the DBW in the 05/06 LS2 is excellent and works how it's supposed to.

bravenrace
bravenrace PowerDork
10/24/12 2:06 p.m.

New LT1 - 450hp from 6.2 liters = 73hp/liter
Mustang Boss 5.0 - 430hp from 5.0 liters = 86hp/liter
Mustang GT 5.0 - 420hp from 5.0 literes = 84hp/liter
Honda S2000 - 240hp from 2.0 liters = 120hp/liter

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