Was the LS3 rated under the new SAE guidelines? I know the LS7 was. If so, the numbers stated are truthful.

I do know that the LS3 seems to be detuned from the factory. The cars seem to respond really well with cheap bolt ons and a tune.

 

I do agree the LS3 has a lot of potential and responds well to basic bolt ons and a cam. The heads are awesome and 6.2L is a lot of motor to work with. I don't think Ford will be leave as much room for improvement with the new 5.0L.

 

Yes, the LS3 is now rated under the new guidelines, but that doesn't necessarily means that it couldn't be under-rated. It is important to remember that under-rating does still occur even under the new guidelines although it is obviously more difficult to manage and when it does happen it doesn't appear to be as extreme. For example, BMW's GTDi 3.0L I-6 is apparently under-rated to the tune of 20-25hp which is a noticeable difference. That said this it is also the largest discrepancy that I am aware of.

Perhaps the guidelines still leave loopholes which allow for a bit of sandbagging with turbo engines? Or perhaps the SAE watchdogs sent to certify the BMW procedures were having an off day? Either way, I think the factory LS3 is rated to the last drop from what we have seen and, in this case, I do think that the SAE numbers are the whole story.

As for the LS3 responding to cheap and easy bolt ons...in naturally aspirated format the LS3 will almost certainly maintain an advantage in this area over the upcoming 5.0L when it comes to swapping major hardware...like camshafts....if for no other reason than there aren't as many. We don't yet know how well the 5.0L will respond to exhaust/intake mods and while LS3 engines do respond well to the same there is no reason to expect less improvement here than we see with competing units. And frankly, we have every reason to assume that the 5.0L V8 will perform better with power adders than the existing mod motors do so nitrous and supercharging/turbocharging could easily be a 5.0L strong point compared to the competition.

 

The LS3 has the displacement advantage, so ultimately it will be easier to make power (FI or N/A). BMW might not have certified the engine using the new SAE regs???

 

NA yes, the LS3 is going to respond better mod for mod largely because of it's displacement. FI, I disagree and I would point to the existing Mod motor engines which compare just fine to LS3 engines in this respect and are arguably superior when the atmosphere turns artificial. The 5.0L will only improve upon this with its larger bore..


The BMW mill is SAE certified.

 

There is no replacement for displacement. I know how well the 3V's respond to boost, but then again I could have made just as much power N/A with an LSX. I don't know why you think the LS3 is inferior when boosted???

 

First, if were talking boost the 4-valve engines in the 03/04 Cobra, GT500, and GT...and even the older naturally aspirated DOHC V8 Mod motors,... are a far more valid benchmark than the existing 3-valve unit since the upcoming five liters head design will have nothing in common with the 3-valve motor. With that in mind, I think you're going to have an uphill battle arguing that LS series V8 engines respond better to supercharging/turbocharging than the Mod motors given the numbers we've seen from blown 4-valve Mod motors over the years. GM enthusiasts often argue that they make more power when blown, but wether the engine is production or aftermarket the reality is that, with reasonably comparable forced induction packages, they just don't.

With the existing Mod motors the huge power increases seen with forced induction are partially a by product of the fact that artificial atmospheres go a long way toward masking if not solving many of the problems caused by the existing 4.6L V8's small bore. Another factor in the Mod motors great forced induction performance is that multiple cams and valves have always responded well to supercharging and turbocharging. With the new 5.0L the larger bore means we likely wont see the same jaw dropping improvements in hp and torque when forced induction is added because the engine wont be handicapped by the same small bore in naturally aspirated trim in the first place.

That said, it will be a phenomenal engine under boost, the difference is that now it will be a phenomenal engine without boost as well.

 

You are comparing apples to oranges. The Cobra and GT500 engines have internals built for boost. My car is blown and the safe limit is 450whp on the stock internals.

In the end, there is no replacement for displacement. This holds very true in both N/A and forced induction applications.

 

My comparison is just fine. I didn't limit this comparison to stock internal LS series V8's and I included the new LS9/LS8/LSA blown LS series V8's in it as well. Mod for mod with comparable forced induction setups LS series V8's don't perform as well as do the Mod motors even with their displacement advantage. The idea that there is no replacement for displacement is unfortunately tied to the notion that all else is equal or can be made equal. And in this respect until the LS grows a set of DOHC heads all else isn't equal and thus displacement, in this comparo, is on the losing side of the equation.

 

I fail to see in you last post where you mentioned "LS9/LSA", but whatever. I don't know how you could be an expert on how they respond to boost, since they really haven't been out in numbers to the public.

I'd suggest that you do a bit of research on the competition. The heads on the LSx work just fine for boost. If you don't believe me, take a peak at the stock flow of 03-04 4V heads vs. LS2/LS3 heads. The aftermarket also has a ton more options if you need to make a ton of power.

 

How difficult is this to grasp? I made a very broad, and obvious for that matter, statement regarding LS series V8's in general. Since I then made no statement excluding any of them so why would anybody presume that the LS9/LSA isn't included? I'm only going to go so far out of my way to make these things more obvious than they already are.

As for comparisons...we already have one that works just fine. The now three year old 5.4L DOHC V8 out of the Ford GT was rated at about 550hp and 500lb-ft of torque and utilized a 2.3L Lysholm twin screw with a single intercooler running 12psi of boost atop a motor with 8.4:1 compression. More important, given the leniency of the old SAE ratings system the GT was, as is well known, massively under-rated. More than one of these cars has dynoed at 550rwhp and 500rwlb-ft of torque. In real world numbers, assuming an extremely reasonable 13% driveline loss that equals about 632hp and 568lb-ft of torque. Using the far more common 15% driveline loss bumps that to 647hp and 580lb-ft of torque, but I've included both here for the sake of argument and conservatism.

The new LS9, which is three years newer and has had ample time to answer this effort, displaces 6.2L and utilizes a new generation 4 rotor roots style supercharger with twin intercoolers running 10.5psi of boost atop a long-block sporting 9.1:1 compression and makes about 620hp and 600lb-ft of torque under the new ratings system. Is it under-rated? Possibly, but under the new ratings system the 25hp under-rated BMW 335 is a virtual freak of nature so we cannot possibly have anything like the fudge factor used on the Ford GT. Given this it's more than reasonable to assume that the hp is, at best, somewhere around the 632-650hp number the Ford GT was actually sporting while the torque number might go as high as 620lb-ft or so.

Here is where this gets interesting. Some may cite the GT's 1.5psi boost advantage and cry foul with this comparison but the reality is that the LS9 has the easy advantage as far as the boost/compression/displacement equation is concerned. First, even the older generation roots superchargers should give the LS9 a torque advantage over the Ford since the Lysholm twin screws tend to give up some torque for higher peak hp. In this case the difference should be even greater because the new generation roots the LS9 uses is seriously improved in terms of friction loss (this is worth at least 35hp on the LS9) and the extra rotor both improves torque and closes the hp gap. Even more, the LS9's .6 point higher compression ratio easily offsets the Ford's lower boost and should further serve to increase overall torque production and overall driveability.

In the end we have a three year newer factory GM effort that displaces nearly another liter more than the 5.4L, uses the most advanced roots blower yet designed and two intercoolers instead of one, and which sports a 9.1:1 compression ratio to the Ford's 8.4:1 compression ratio but the Chevy only manages similar hp at best...the Ford may very well prove to have more hp since I'm giving Chevy decent room for serious under-rating under the new standards here....and the Chevy might possess as much as a 40lb-ft advantage in torque but more than likely possesses a smaller advantage than that.

GM's new factory effort to Ford's last gen factory effort and we end up with a near wash despite a very large advantage in cubes.....color me unimpressed. The updated 2011MY GT500 engine is almost assured to meet or exceed this thing.

 

The fanboism runs deep in you. You are comparing apples to oranges. Ford is running a much more efficient (In CFM and IATs) twin screw. GM is still runing a roots blower. It will be interesting to see what happens when Whipple develops a twin screw for the LS9. It will make more power at the same PSI, just like we see with the GT300 and 03-04 Cobras.

The GT has a great intercooler. Heffner uses the stock unit in their TT kits. We don't know the limits of the ZR1 intercooler right now, but hopefully it's as good as the GT's.

You and I don't know how much power the LS9 makes. It makes "at least 620hp". I bet we see 650 when all is said and done. In the end, we are looking at 10-40 more crank hp than the GT. We also might find that GM has de-tuned the car, much like it appears they've done with the LS3. Ford/GM recently have really pushed torque management aggresively. Your comparison has way to many variables in it to be valid.

Like I said, I'd do some research on some GM forums. If you posted, "LSx's don't respond well to boost", you'd get laughed/flamed off the board. We can talk about this all day back and forth. The Ford GT is a great engine and the LS9 is a great engine. In the end, the the LS9 powered car will be faster down the track. Isn't that what matters?

 

[quote=max2000jp;5555243]I figured you would break this one out. You always throw the fanboy card when your argument is approaching empty.

First of all, your generalizations about roots blowers and twin screws is far too...well...generic. A twin screw is not just a twin screw and a roots is not just a roots.

First of all you compare what the Cobra gains with a whipple to what we can expect from the LS9 when the reality is that the Cobra's Eaton and the blower on the LS9 are fundamentally different. Design improvements have seen the roots blower on the LS9 grow another rotor entirely and seriously reduce internal friction. Right now the improvements are significant enough to question the validity of Lysholm branded twin screw superiority compared to the newer roots altogether unless peak hp is the only measurement you are using. A twin screw Lysholm will almost certainly still provide more hp per lb of boost than the revised roots but the difference wont be as large as before and the roots will continue to maintain an advantage in low and mid range torque compared to the Lysholm twin screw and the roots will absolutely expand on that given the improvements. Factor in two intercoolers to the GT's one and you are going to have a difficult time explaining how the LS9 is handicapped here.

The GT unit works very well, but the dual brick intercoolers the LS9 ZR1 is running are absolutely ultra-high tech stuff and are superior. Kudo's to GM for upping the ante here, but the reality is it's another advantage for the LS9 that doesn't translate into the power advantage we should be seeing if the LS is the obviously superior piece you make it out to be

The hp rating is going to be closer to 620 than 650, and I even allowed enough leeway for a legit 650hp rating for the ZR1 here so I fail to see where the problem is. In the end we are looking at about the same crank hp the GT had in a three year newer engine displacing .8L more. As for GM detuning the LS9, last time I checked the GT engine was seriously detuned so yet again we have a wash at best.

I didn't say the LS doesn't respond well to boost, I said Mod motors respond better.

I found this part particularly interesting since this entire debate started primarily because I said that the 5.0L appears to be a superior engine to the LS3 largely because it's almost certain to be better at accomplishing it's primary mission....push the 2010/2011 Mustang GT down the road faster than the LS3 moves the Camaro down the road while using less gasoline in the process.

 

[quote=jsaylor;5555611]It’s a card that needs to be played. You are SO biased towards Ford, you cannot have a logical argument to a guy that isn’t a brand loyalist.


Show your tech or shut it. Either post some data, or quit your argument. I can post various sources that refute everything you state above. Either play your “card” or quit your babbling. Oh yea, I have real world dynos that show that what twin screws hold an advantage down from idle on. I’ll wait, but I doubt I will get any tech data that supports your opinion above. The fact say otherwise!

As for intercoolers, we know that the Ford GT intercooler is good to 800hp+ and 18+lbs of boost. How much is the ZR1 good up to? I can also tell you this from experience on my supercharged car that the physical heat exchanger size and pump make a huge difference. The Ford GT’s pump flows a lot more than the 03-04 Cobra that most S197 blower kits use. It’s **** pricey too! No specs are present on the ZR1’s system besides the twin intercooler.


See above and show your tech that supports that either one is superior. How much hp is the ZR1 intercooler rated to?


I’ve seen dyno’s of them too. I can post them if you like. They were done by some of the best modular tuners in the US (Eric Brooks & Justin @ VMP). They put down 530ish to the wheels. That’s not 620 to 640 when you do the math at 15%. We both agree that the GT is detuned from the factory. Why couldn’t GM employ the same methodology? Again, we know that the LS3/LS7 respond very well from a tune that adjusts torque management (along with the usuals).


That’s your opinion and far from factual.

What does the LS3 make in the Camaro? What does the 01/11 5.0L make? Start shaking your magic 8 ball. You only look at engine development from the Ford standpoint! GM’s engineers could very well be adding DI, AFM, and VVT to the LS3 due to CAFE or maybe because of the COMPETITION!!

 

IIRC the Gen V LS motors will feature those innovations, from what I understand, the Gen V 6.2 is an easy 500hp motor.

Having a 12 second capable GT for under 30k is pure awesome, but I have to wonder if such a thing comes true, where will it end?

What will GM's response be? Counter with a 500hp Camaro for under 30k? Then what will Ford do? It wouldn't make much sense to have the GT500 barely outpacing GM's entry V8 car at nearly twice the price.

Then again, safely and reliably adding horsepower adds weight and it beocmes a game of diminishing returns (the GT500 is the poster boy for this).

 

Please, you've made it more than obvious at this point that anybody who doesn't agree with you will be branded a fanboy.

So you've got dyno data that shows a twin screw holding an advantage over a sixth gen integrated Eaton? I thought the only engine even wearing one of those thus far was a ZR1, but if you've got something of substance on this engine not already posted in this thread all i can say is bring it.. I've already stated that the ZR1 engine produced about 620hp and 600lb-ft of torque in production trim and was extremely close to production numbers. (638 and 604 respectively) I even gave you a good minimum figure for efficiency improvement with the integrated Eaton....combine this with what will unquestionably be far superior torque production since even the older roots blower built by Eaton, which suffer from far greater drag and make do with one fewer lobes, hold an advantage here.

But don't let me interrupt your continuing strategy of simply ignoring anything that doesn't suit your argument.

Here we go again. Max boost pressure and max hp ratings for an intercooler and how well that intercooler works on a production engine at stock boost levels are two separate issues.

It never ends. They are superior because of where they sit in the engine and how they accomplish their task. Integrating the supercharger and intercooler into one package creates a virtual straight shot through the intercooler and into the cylinder head. Less distance to travel and a straighter path into the engine are huge advantages with any itntercooler and make for greater power for reasons which should be obvious. The same tech has been used on intakes for decades now and to great effect. The advantages only get better when supercharging is involves. Unless you want to argue that you think GM drastically undersized the intercoolers on the ZR1 you are going to be hard pressed to argue that any of this is anything but an advantage

Even using your 540rwhp number we end up with 540/.85=635hp at the crank.

Please, we already know the amount of tech both engines will be packing for the 2010/2011 model year and we likewise already know a best and worst case hp/tq scenario for both engines. Factor in the unquestionably far lower weight of the Mustang GT and this isn't rocket science.

 

Nope, just people like you who can't have a reasonable conversation using both points of view.

Actually we do. Again, you aren't doing your homework! Cough Cough....Ford Racing (Eaton 6th gen) TVS blower



How much HP and boost is the ZR1 intercooler good for again?


Um, have you ever looked at a intercooler before, specifically the units on twin screw or roots. Below is the stock Ford GT intake manifold with intercooler built in. Both GM and Ford use the same principles. GM's "twin" intercooler was most likely used for packaging reasons.




540 X .15 drivertrain loss = 81

540 + 81 = 621 at the crank. Am I missing anything here?

No we don't until the car was in production. We are almost two years out until the 2010/11 is produced. You are reading the rumors the same as I. Do we need to use the 03 Cobra motor as an example of last minute changes to engine developement?

 

I played with some numbers when I got my dyno done on my '05. But anyways, based on your 3600lb, 360ft-lb and some arbitrary gearing numbers (for example purpose) this might be what you're looking for:

360ft-lb x 3.0 gear (~1st gear-ish) ratio = 1080ft-lb
1080ft-lb x 4.10 gear (weee!) ratio = 4428ft-lb
4428ft-lb x 12in/ft (conversion) x 1/27in (tires) x 2 (radius, or use 12/27/2 = 24/27) = 3936lbf
3936lbf / 3600lb = 1.093 Gs acceleration

Given an LS3 rated for 430/400 at 4000lb same gears and tires... we end up with:
400 x 3.0 = 1200
1200 x 4.1 = 4920
4920 x 24/27 = 4373
4373 / 4000 = 1.093 Gs ... Weird how that works, huh?

[keep in mind this is all theoretical, actual weights and torque numbers will vary, and traction will be limited ]

The 15% loss (estimate ) is taken from crank, not 15% more than your readout from the wheels.

So back-calculating from your 621 x 15% = 93.15

621 - 93 = 528 =/= 540

81hp drivetrain loss on 621hp is 13% (IMO, more realistic than 15%), but nevertheless, your math-ing process was backwards. (As for the rest of your argument, I'm staying out of it. )

 

After all the crap I've seen the best policy to use whenever max2000 jumps in a thread is to just not talk, regardless if you are a professional or expert. You just can't win because you can't argue with ___ ,fill in the blank yourself. I refuse to get another temp-ban because you seem to have the admins by the collar and can never concede.

Even when though i do agree with you on this current issue and argument max, the way you go about it is absolutely appauling for someone who claims to be college educated and for that matter a working business man. I'm still a student and I can and will say more stupid things as I mature, but I never see working adults argue like you, and I hope I grow up by the time I'm finished, unlike you...for everyones sake.

Please respond too max, I love wasting your time, but you won't get the satisfaction of ruining my night this time, because this is as far as it goes.





Just for clarification, a lot of the insiders on the camaro5 forums are suggesting that the curb weight will be around 3700-lb's, unfortunatly speculation between the L76 and a AFM LS3 for the base v8. Word has floated around of the Gen V engines as well, but like Ford they don't expect it to be ready for the first year of production.

 

Kyle, you haven't realized that this is an internet forum where people express their opinions. Either realize that or stop visiting message forums.