JD_AMG

So you don't like cheaper, more powerful engines?

Because like I said the drag world is a bunch of sandbagging BS, and there is no real proof of whats legit or not. And my argument was never which made more power, just clearing up some biased/wrong info.

Thanks for all the links, and proof posted.

A supercharged engine that's bigger, and heavier than the LS7 while not making as much power? Thats real impressive...
The Northstar is no small V8...
The LS1/6 are around 390lbs undressed, LS2 is in the low 400s, and the LS7 is 440lbs.

Now were getting somewhere, although you have to read everything with a grain of salt.
So save a few hundred over, say, an LS6 but have a total lack of aftermarket support in comparison? Doesn't seem worth it to me... Believe it or not most people are about making reliable power for as cheap and easy as possible, not just making power to make power out of a given engine.

No need to type all that, sorry. I was simply making a point that just because its DOHC doesn't automatically make it more powerful (like LEO implies). Its all about what the manufacturer wants. GM didn't want/need more than 405hp out of either, although each could make way more.

HioSSilver

iTrader: (8)

A ls7 is not 440 lbs...a typical aluminum block ls engine is around 360 minus acc. How the hell would a ls7 gain 80#'s....even the dry sump stuff won't weigh that. I have a ls7 I'm converting to wet sump....I'll let ya know what it weighs in a few weeks.

ThisBlood147

When you're using it as a bragging point for an engine, yes. Some of you are arguing as if these motors drive around on the street with 4 tires and a steering wheel attached. In the real world these motors ride around in actual cars...which have their own weights and measures. So it's rather pointless to argue over hp/lb when talking about the motor itself. Case in point: the new 5.0 GT vs the new Camaro SS. The SS makes more power, but is typically slower than the GT because of it's weight.

So the only way arguing hp/lb when talking about the motors themselves holds any real weight is if you're talking about them from a motor-swapping, hotrodder's perspective. And that's a pretty niche conversation considering we're talking about what modern 2010/2011 MY production engines are making with a small to moderate list of mods. No one is pulling motors here.

Yes, HP/lb matters.......when you're talking about the whole package: chassis + engine. Bragging/arguing over HP/lb when talking about undressed motors that aren't actually doing any work inside of an automobile's enginebay is just as much ricer math as HP/L.

And just to clarify...I'm not defending the HP/L argument by any means. I just found it strange that you would decry the use of ricer math by others only to resort to using your own.

redsap05

This is pretty bad ***, with just a laptop you can increase the size of your cam and get a sweet idle, and more power. amazing
http://www.youtube.com/watch?v=bBP4dyCxoZQ

It'llrun

The only variable is how the DOHC is built, regarding cams, most specifically. The heads, by general design, are outstanding. The design also allows for more rpm in general. From that point, the choices make the difference in overall performance. Even at 15-30 lb heavier, it's bound to win in the end. It's simply a better design for performance. The next concern is the strength of all the various parts in combination.

Sure I do... However, if I'm looking for all out power, I'm ONLY looking for the most power and to that end, DOHC engines win, period. No, it isn't debatable... They just DO! It's like that tired old agument that nitrous is better than S/C's and S/C's are better than turbos... Well, there was a time when that was the case. That time has passed and the fortunes have reversed. Today, turbos are the way to go for biggest power, generally followed by S/C's and then nitrous. It just is what it is.

If your argument was never which made more power, please try explaining the quote above this one... You just said your argument about more power was never about more power...

It isn't as if this info is difficult to find.

They managed to fit it into the XLR... If it fits into a Corvette style car, it's usable in nearly all others. Topping that is the fact, they could've done even more good things with the DOHC. I'm not about to say I don't like the compactness of the LS series, but if that's the only beneficial argument... not gonna work.

Yeah... 418, 415.. whatever. Who drives around without an alternator??? C'mon, a long block doesn't get us down the road, so it hardly matters what a nearly complete engine weighs. 390 is simply not the "as used" wright. Besides, the overall vehicle weight matters more, along with distribution(for traction reasons). I think I can find a way to remove 30 lb from the average vehicle... Then it's even... except vehicle weights always vary.

Always... Can't just trust all we read to be completely accurate.

Well that's what I've been saying. You're the one who wanted to argue cost... The LS3, carbureted from GM lists for $8,750... No carb included. The 5L including fuel injection is 7k... EITHER can be purchased for less than their advertised price, making them about equal overall.

Since you said price matters, I submitted a reason to overlook price to a degree... You've made my point for me. Many people will spend more for better overall performance.

Aftermarket performance products come when the aftermarket deems an engine has potential. If there's really no aftermarket for the 4.8L, it's because the producers have determined that one isn't worth the time vs others. This could be due to cost, or lack of positive end results. Either way, the 4.8L is no 4.6L and that's about as close as the whole "contest" could get. Even with the slight cubic inch advantage, the OHV gets trounced instantly in that contest.

We see that point, but it's not really valid... Compare the LT5 to the LT1 produced at the same time for a much clearer picture of what we had there. The LS series shares VERY LITTLE with the SBC it replaced.

An older DOHC won't look so grand against a new one either. I may as well compare the 2003 4.6L Cobra engine to the 2011 5L in the GT... Both are Mustangs and each has its advantages. Better still, a 1996 Cobra or even a 2003 Mach 1... The 5L isn't that much larger, but it sure performs like it is, with another 100 or so hp.

Had GM stuck with a 4V for the Corvette or used it in the Camaro and taken it to the "normal" performance DOHC V8 arena, I can say WITHOUT QUESTION, you'd praise that plan. I know this because a 7L DOHC could be a 700+ hp monster in N/A form. It could be even more in aftermarket hands. See even the 7L Ford SOHC... 800hp, N/A.

Bottom line never changes: DOHC has too many advantages over the OHV in the end. In this case, the 5L makes that point brilliantly, by outperforming even most larger OHV's. If the OHV needs to be 1 liter or more to match the performance, we just know there's a limit and there will be a time the DOHC simply enough, just passes the OHV overall... Maybe it'll require a 6-7L DOHC, but it isn't like that can't be done. Are we going next to an 8, 9 or 10L LS? At some point, we'll be out of cubic inches available.

JD_AMG

I wouldn't doubt the LS7 to be lighter, these are just the #s Ive been seeing from crate LS7 engines, and according to GM performance parts.

We are comparing engines here not cars. When comparing engines alone, weight and size most certainly matter. The smaller the engine the lower, and closer to the center of the car you can put it, and of course weight is bad for anything. In the real world people are putting LSx engines into their cars (mustangs included) because of size/weight and power.

JD_AMG

That was my whole point. Just because its DOHC doesn't mean they made it to make the most amount of power they could possibly squeeze from it.

Until you cannot fit it into the car... In not knocking DOHC in anyway, just pointing out some simple facts here that too many fanboys ignore.

Pretty sure no one is arguing against this. Given all else equal (which again almost never happens) a DOHC should be capable of making more power for the simple fact the valve train allows for higher RPMs than what a pushrod engine can do.
This is great for dyno racing, but doesn't always make for the best car (and certainly not the best street production car where no one is looking for "all out" power.)

Not about absolute highest power possible, but about bang for the buck. More power for the money.

Yes, it barley fit. But who is to say they couldn't do more to the LS's? Again ill ask, for a street production car (like the XLR or Corvette for example) whats the point of having a heavier, bigger engine that makes less power over a lighter, smaller engine that makes more? - neither engine is close to their potential, but they are not supposed to be...

Because thats how most manufacturers rate them, unless of course you want to compare fully dressed engines to undressed ones?

And exactly why the engine being lighter and smaller matters, you can mount it lower and closer to the center of the chassis...

Um for cost, Im pretty sure it would be cheaper to build an LS engine to x amount of power vs an LS 4.8L to that same x amount of power...

I don't believe you can be this dense, or is it pure fanboyism?
Look at where these engines are coming from, the 4.8L is from a truck, while Ford 4.6L is from a performance car (and same as the LS engines). Who do you think is going to have better aftermarket support?

Again, totally over your head on this one, just let it go.

Eh, not so much. The Corvette would be a larger, heavier car, and much more expensive. The Corvette is a sports car, its not some one trick horse that can only go strait, it does it all so weight and weight distribution count a whole lot more.
Read through this:
http://www.corvetteactioncenter.com/...t5-engine.html
And the LS7 can be a 700+hp monster. But this is what is all boils down to, these are supposed to be street production cars, 700+hp is total overkill for that, and for any real racing (road course). I MUCH rather have a sub 3000lbs car with less power than a 3500Lbs+ car with more power - everything else equal.

This is where we disagree, and you need to be more specific. In a very rule happy limited race series, DOHC may have the upper hand simply because they are capable of revving higher (as I already mentioned). But in a street production car when no one is trying to make the most power, or the most power out of a particular engine, DOHC in a V configuration (like a V8) has more downsides than upsides compared to the lighter, smaller and often cheaper pushrod engine.

Once again with the "needs to", who says it needs to be 1L bigger? Just because the only current comparable engine happens to be a 6L or 6.2L?

We won't need to get to that point though, as once again we are talking about street production cars, not making all out power. Do you honestly think that Ford or GM are going to be shooting for even higher power for their street cars? -Ignoring all the EPA bs that going on right now, just simply think about the chassis and suspension and brake design for more power, then running on street tires.
I honestly don't see a Corvette or Camaro topping the 640hp LS9 for the simple fact that its already overkill for a performance street car. So if they are going to be shooting for 600hp or lower, why bother with a heavier, bigger, more costly DOHC engine when they could use their lighter, smaller, cheaper pushrod engine?

GMmexican

iTrader: (7)

Not its not c6 vettes go for as cheap as 30k and c6 z06 vettes have been as low as $38

You CANNOT get a clean ford gt supercharged for under $40,000

Cammed 02

That is impressive.

However, this stock LS1 Heads/Cam dyno is far more impressive at the same power level. Look at tq.

Marc 85Z28

iTrader: (8)

You're confused.

$6999 won't buy you a running 5.0. You still need the $1800 PCM and harness.

So you tell me... $7800 for a 415hp engine, and good luck squeezing it into your donor car.

OR...

$7200 for a 515hp engine, that needs another $500 for a carb and it will drop into ANYTHING you wish, easily.

GMmexican

iTrader: (7)

I have seen LSx motors purchased for far less than that...its no secret the lsx swap is the most popular and effective swap on earth

Marc 85Z28

iTrader: (8)

He was talking about factory offered crate engines.

1slow01Z71

iTrader: (36)

I didnt bother reading most of the banter back and forth but just an FYI the 4.8 has made almost 800rwhp in a truck so it can make power just fine, but nobody cares to use it since there are easier options.

LEO

iTrader: (3)

Wow! Your debating skills are almost as good as the kids riding the short bus.

ramairroughneck

iTrader: (35)

So the morel of the story is add twice as many valves, four times as many cams, and direct injection, and you get more power per cube. Somehow thats better? I wonder how much power could be had only adding a lean burning direct injection to our current ls motors. Not that I really care. I'm pretty satified with the power available with aftermarket parts.

It'llrun

Whatever... The LS2 was rather well done from the start. The LT5 was all but a 1st time effort for GM. Overall though, even that older LT5 can offer havoc against it. I wouldn't be surprised if GM limited the rpm of the LT5 and that was the main reason for "only" 400hp.

I've seen a 4.6L in a Miata... So it's just not a problem worthy of major concern. People who want something badly enough will do what it takes to get it. If we max out the OHV engine in current form, and have to make it larger to compete with DOHC's, it still gets to a point of not fitting, which is the typical complaint about DOHC's.

Maybe they won't... Then again, that's not just the top dog, it's got a standard power adder... Once the EPA prevents the engine from being profitable or outright bans it, they'll switch to something.

They could get more power from a lighter DOHC than the LS9 provides. Remember, this is NO lightweight. 800hp from a SOHC that weighs about the same and has no power adder...

Is the LS9 cheaper... Superchargers aren''t free, even for GM. The LS9 is a $21,000 engine from aftermarket sourcing. JEGS gets nearly 23k for it.

Adding the S/C also increases the overall size of the engine. Not saying it's smaller than a large DOHC, but it's not terribly smaller anymore.

For years we bagged on Ford for "NEEDING" a supercharger to compete... Now that GM is back to their power adders(which they've pretty much used regularly since 1980), it's all good...

I'm debating DOHC capability vs OHC... You're basically debating GM vs Ford.

It'llrun

It seems you think the 5L has direct injection. It doesn't... yet. Once added(and it is built for it), many suspect it will be near 500hp as Ford sells it. If they also use twin turbo's like the 360hp 420 lb-ft 3.5L V6, who knows...

It'llrun

Why tell us that the LS3 can be purchased for less than MSRP and then in the same post, only state the full list price for the 5L? List for list, or low for low... Not low for one and high for the other. The entire 5L package can be had for about $7600 from what I remember reading... And it's got EFI. Upgrade to EFI with the LS3 and where's the price?

nmass399

The 4 valves are only as good as the stock heads can be made, because i have yet to see any aftermarket castings out there for a 4 valve engine. I expected more from the flow #'s of the 5.0 heads but they seem to do pretty well. It would have been nice if Ford had put some cubic inches into this engine, i would have been happy.

kennyxg

iTrader: (1)

Well then just drop a new 5.0 crate motor with c4 into a fox body coupe, painless wiring harness nitrous tune with bolt ons and still pretty much own the road maybe 10 k investment including car. like I said this is a stupid argument with out deep pockets. Drop a head and cammed ls whatever. you are still gonna spend the same $.. to do it right any way. The 5.0 motor will be just as cheap as a used ls motor as soon as more turn up at the bone yard. I guess just pick your poison..In the end it just takes money.