GM V8 4 Valve?
06-05-2010, 06:15 PM
#101
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your name explains it all. Keep hoping ford will make something that'll run with an ls1( a motor not even in production anymore). Amazing how ford seems to be about 10 years behind on everything. You probably dont know this but 5.4 heads used to blow plugs out alittle fyi
Complexity does not mean a more efficient motor, the bottom line is efficiency. Not the amount of valves. K.I.S.S. is a well earned abbreviation. Many manufacturers (including GM) abide by this religiously to retain big power and big reliability.
Besides, if GM is so "religious" about it, why does GM offer a 443hp DOHC? It's only 4.4L and makes more power than anything else GM offers, short of the ZO6 and ZR1 engines. Imagine the same engine at 6.2 or 7.0 liters... 700hp would be rather easy.
You do have a good point using smaller dur cams (with DOHC 4v) and optimizing the head to use the dur and lifts, but this can also be done with a 2 valve design the same way, just like GM did, which is what this discussion is about.
End of story? Who are you? end of story that's funny. Again we're here to discuss. you sound 16 and a HALF
Yeah and the Northstar has been superseded by the LS motors...Ya know the non DOHC ones. Fact. end of story
Facts? Did your mom confirm these "facts" or was this another Ford thing?
More importantly, while you nuthuggers can't see past the brand name which makes you cream your droopy, sagging pants, it's NOT about Ford... It's about DOHC engines and, NEWSFLASH... Ford is hardly the only company making them. In this case, there was a silly comment that Ford DOHC engines must have forced induction... Comparing 2 Ford engines one of which is only an SOHC, we can easily see F/I isn't required to make power.
I have NO problems with the LS series... None. That doesn't mean I can't also have no problems with a DOHC engine. We're done here... right?
06-05-2010, 08:52 PM
#102
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omg lots of **** contests here. guess what i have yet to see a streetable 600whp mod motor n/a if there so damn badass then present the proof.
yeah maybe ls motors would be a whole hell of alot more powerful IF we had some type of 4v system. but there were a lot of reasons the lt5 didnt stick man. maybe it was just cost or maybe they found a way to make 2v small block heads outflow bigblock heads... for a whole lot less money...
yeah maybe ls motors would be a whole hell of alot more powerful IF we had some type of 4v system. but there were a lot of reasons the lt5 didnt stick man. maybe it was just cost or maybe they found a way to make 2v small block heads outflow bigblock heads... for a whole lot less money...
06-06-2010, 11:45 AM
#103
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I have no clue, really? Thats weird cause your the guy arguing with everyone else on a chevy board about ls1s touting how much better ford dohc v-8s are. Just as dohc engines have evolved so has the ls engine family. Its called upgrading and as technology progesses so do cars thats why their are ls3s. I guess since your so in loop your going to tell me how ls1 heads were based off a ford design too. I wish i had clue and an engineering degree like you apparently possess.
If you even resembled someone WITH a clue, I'd probably still not be concerned with your comment. You don't though, so it's certain that I don't care. Go look into what's what in the world of racing and answer for yourself how the LS1(not later, larger and much better versions) stacks up against what Ford makes regarding DOHC V8's. The end result is, LS1 isn't even close. Sad, but true... It's not close. When you're done, you'll surely know why GM no longer uses it.
I'd find it problematic, at very least, to think Wikipedia is a good source for serious information. Not only will I not take your advice, but I'll offer you some advice to NOT defer to that nonsense as a final result. Even though much of it is copied from elsewhere, it may be changed and added incorrectly...
It's not about efficiency... But I don't get it, when one argument doesn't work, we seem to switch to another, in hopes of winning points or something. It's about cleaner engines, and that(to me) is stupid, but oh well.
Besides, if GM is so "religious" about it, why does GM offer a 443hp DOHC? It's only 4.4L and makes more power than anything else GM offers, short of the ZO6 and ZR1 engines. Imagine the same engine at 6.2 or 7.0 liters... 700hp would be rather easy.
GM also does it with 4v's like most other manufacturers these days. And no matter what you think, 4v's offer better flow with less duration and lift. It's a proven fact, not a conception of this thread. And btw, NO, it cannot be done the same way with a 2v.
I'd almost wager that you were 16 more recently than I was 35, but surely you know I'm not 16 anyway. The "end of story" comment was about a particular point, believe it or not. It's still there to see, btw.
Don't look now but... GM still makes the Northstar engine. That makes it unquestionable that the LS "motors" didn't supersede the Northstar... When one supersedes another, that which was superseded is no longer offered... the replacement is.
Yes, the facts... No, I didn't check with mom... She's not exactly into engines... in her 70's and all...
More importantly, while you nuthuggers can't see past the brand name which makes you cream your droopy, sagging pants, it's NOT about Ford... It's about DOHC engines and, NEWSFLASH... Ford is hardly the only company making them. In this case, there was a silly comment that Ford DOHC engines must have forced induction... Comparing 2 Ford engines one of which is only an SOHC, we can easily see F/I isn't required to make power.
I have NO problems with the LS series... None. That doesn't mean I can't also have no problems with a DOHC engine. We're done here... right?
I'd find it problematic, at very least, to think Wikipedia is a good source for serious information. Not only will I not take your advice, but I'll offer you some advice to NOT defer to that nonsense as a final result. Even though much of it is copied from elsewhere, it may be changed and added incorrectly...
It's not about efficiency... But I don't get it, when one argument doesn't work, we seem to switch to another, in hopes of winning points or something. It's about cleaner engines, and that(to me) is stupid, but oh well.
Besides, if GM is so "religious" about it, why does GM offer a 443hp DOHC? It's only 4.4L and makes more power than anything else GM offers, short of the ZO6 and ZR1 engines. Imagine the same engine at 6.2 or 7.0 liters... 700hp would be rather easy.
GM also does it with 4v's like most other manufacturers these days. And no matter what you think, 4v's offer better flow with less duration and lift. It's a proven fact, not a conception of this thread. And btw, NO, it cannot be done the same way with a 2v.
I'd almost wager that you were 16 more recently than I was 35, but surely you know I'm not 16 anyway. The "end of story" comment was about a particular point, believe it or not. It's still there to see, btw.
Don't look now but... GM still makes the Northstar engine. That makes it unquestionable that the LS "motors" didn't supersede the Northstar... When one supersedes another, that which was superseded is no longer offered... the replacement is.
Yes, the facts... No, I didn't check with mom... She's not exactly into engines... in her 70's and all...
More importantly, while you nuthuggers can't see past the brand name which makes you cream your droopy, sagging pants, it's NOT about Ford... It's about DOHC engines and, NEWSFLASH... Ford is hardly the only company making them. In this case, there was a silly comment that Ford DOHC engines must have forced induction... Comparing 2 Ford engines one of which is only an SOHC, we can easily see F/I isn't required to make power.
I have NO problems with the LS series... None. That doesn't mean I can't also have no problems with a DOHC engine. We're done here... right?
06-06-2010, 12:13 PM
#105
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If you even resembled someone WITH a clue, I'd probably still not be concerned with your comment. You don't though, so it's certain that I don't care. Go look into what's what in the world of racing and answer for yourself how the LS1(not later, larger and much better versions) stacks up against what Ford makes regarding DOHC V8's. The end result is, LS1 isn't even close. Sad, but true... It's not close. When you're done, you'll surely know why GM no longer uses it.
Gm is still using the same LSx series engines while Ford has changed up the mod motor quite a bit from the 4th generation pusstang to the 5th gen, and now the 2011 model. None of which have made the power (or better yet power/torque to weight of the engine) that the LSx series have.
And Ill give you the benefit of doubt since you have clearly shown your ricer/ford bias, but have you noticed that the LSx engines have been the most commonly swapped engines in the past decade? And including into many many DOHC cars, like even the mustang...
And all these commonly swapped cars (like the Miata, RX7, 240SX, Mustang, Porsche 944, BMWs, uncountable 60s muscle cars, just to name a few) have LOST weight while gaining a significant amount of power, torque and increased gas mileage. There are even people swapping LSx's into Sti's, EVOs, and S2000s...
And what about all the various supercar companies that are using the LSx instead of a "high tech" OHC engine? Hennessy's new creation based on the Lotus Elise (the GT), the Mosler, SCC Aero, and the Ultima GTR just off the top of my head, and many many others. These are record breaking cars, so why would they be "settling" for less of an engine?
Besides, if GM is so "religious" about it, why does GM offer a 443hp DOHC? It's only 4.4L and makes more power than anything else GM offers, short of the ZO6 and ZR1 engines. Imagine the same engine at 6.2 or 7.0 liters... 700hp would be rather easy.
Lets try something, next time you have the urge to say something like "well if x engine had x displacement then blah blah blah" walk away from the keyboard, take a deep breath and realize that x engine has that much power because the manufacturer ONLY WANTS THAT MUCH. Do you really think the engine is maxed out, or they couldn't figure out how to get more power out of it? Whats to stop them from running a more aggressive tune, and a pulley to make more power?
GM has said it themselves(look at my previous post), they have OHC V8s around still because of MARKETING, for people like you who circle jerk to the OHC engine.
The FACT of the matter is the LSx series are still lighter, smaller, and less expensive while making more power (and N/A at that...)
06-06-2010, 03:46 PM
#106
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All these arguments have been done over and over and over again. If DOHC wasn't competitive, and the government didn't require cleaner engines than the LS series has been to date(and those emissions are already law), nobody would be advancing DOHC engines for American cars, INCLUDING General Motors... But alas, they are.
We can expect smaller engines in our future. Less cubes, that is.
JD... Please take a moment to consider your "ricer math" argument... You've tried to use it more than once and yet, you also make the argument that DOHC engines don't have the power/torque to weight of the LS series. It that isn't "ricer" math, neither is anything else.
And to the last part... I take it you're referring to the 500+ CI LSX block, correct? How cheap is that, anyway?
By the way, MARKETING never built a single engine... Not to mention the LS series is "marketed" far more than any DOHC I've heard of in the past. Just ask a general auto fan what powers the Camaro SS or the Corvette, or maybe even the full size GM trucks... Then ask them what powers the Cadillac XLR-V and see which offers the blank stare most often.
We can expect smaller engines in our future. Less cubes, that is.
JD... Please take a moment to consider your "ricer math" argument... You've tried to use it more than once and yet, you also make the argument that DOHC engines don't have the power/torque to weight of the LS series. It that isn't "ricer" math, neither is anything else.
Irony at its best...
Gm is still using the same LSx series engines while Ford has changed up the mod motor quite a bit from the 4th generation pusstang to the 5th gen, and now the 2011 model. None of which have made the power (or better yet power/torque to weight of the engine) that the LSx series have.
And Ill give you the benefit of doubt since you have clearly shown your ricer/ford bias, but have you noticed that the LSx engines have been the most commonly swapped engines in the past decade? And including into many many DOHC cars, like even the mustang...
And all these commonly swapped cars (like the Miata, RX7, 240SX, Mustang, Porsche 944, BMWs, uncountable 60s muscle cars, just to name a few) have LOST weight while gaining a significant amount of power, torque and increased gas mileage. There are even people swapping LSx's into Sti's, EVOs, and S2000s...
And what about all the various supercar companies that are using the LSx instead of a "high tech" OHC engine? Hennessy's new creation based on the Lotus Elise (the GT), the Mosler, SCC Aero, and the Ultima GTR just off the top of my head, and many many others. These are record breaking cars, so why would they be "settling" for less of an engine?
And here we go again with the ricer math...
Lets try something, next time you have the urge to say something like "well if x engine had x displacement then blah blah blah" walk away from the keyboard, take a deep breath and realize that x engine has that much power because the manufacturer ONLY WANTS THAT MUCH. Do you really think the engine is maxed out, or they couldn't figure out how to get more power out of it? Whats to stop them from running a more aggressive tune, and a pulley to make more power?
GM has said it themselves(look at my previous post), they have OHC V8s around still because of MARKETING, for people like you who circle jerk to the OHC engine.
The FACT of the matter is the LSx series are still lighter, smaller, and less expensive while making more power (and N/A at that...)
Gm is still using the same LSx series engines while Ford has changed up the mod motor quite a bit from the 4th generation pusstang to the 5th gen, and now the 2011 model. None of which have made the power (or better yet power/torque to weight of the engine) that the LSx series have.
And Ill give you the benefit of doubt since you have clearly shown your ricer/ford bias, but have you noticed that the LSx engines have been the most commonly swapped engines in the past decade? And including into many many DOHC cars, like even the mustang...
And all these commonly swapped cars (like the Miata, RX7, 240SX, Mustang, Porsche 944, BMWs, uncountable 60s muscle cars, just to name a few) have LOST weight while gaining a significant amount of power, torque and increased gas mileage. There are even people swapping LSx's into Sti's, EVOs, and S2000s...
And what about all the various supercar companies that are using the LSx instead of a "high tech" OHC engine? Hennessy's new creation based on the Lotus Elise (the GT), the Mosler, SCC Aero, and the Ultima GTR just off the top of my head, and many many others. These are record breaking cars, so why would they be "settling" for less of an engine?
And here we go again with the ricer math...
Lets try something, next time you have the urge to say something like "well if x engine had x displacement then blah blah blah" walk away from the keyboard, take a deep breath and realize that x engine has that much power because the manufacturer ONLY WANTS THAT MUCH. Do you really think the engine is maxed out, or they couldn't figure out how to get more power out of it? Whats to stop them from running a more aggressive tune, and a pulley to make more power?
GM has said it themselves(look at my previous post), they have OHC V8s around still because of MARKETING, for people like you who circle jerk to the OHC engine.
The FACT of the matter is the LSx series are still lighter, smaller, and less expensive while making more power (and N/A at that...)
By the way, MARKETING never built a single engine... Not to mention the LS series is "marketed" far more than any DOHC I've heard of in the past. Just ask a general auto fan what powers the Camaro SS or the Corvette, or maybe even the full size GM trucks... Then ask them what powers the Cadillac XLR-V and see which offers the blank stare most often.
06-06-2010, 04:58 PM
#107
It just sucks that a thread like this started out strong then ended up like this. It's just the personal attacks guys, this is LS1tech, not JERRY!!! JERRY!!! JERRY!!! Seriously, nobody cares about a 60 yr old interested in proving a point to "would-be 16 yr olds" late on week end nights...seriously get a different hobby.
06-06-2010, 05:57 PM
#108
Douchebag On The Tree
It just sucks that a thread like this started out strong then ended up like this. It's just the personal attacks guys, this is LS1tech, not JERRY!!! JERRY!!! JERRY!!! Seriously, nobody cares about a 60 yr old interested in proving a point to "would-be 16 yr olds" late on week end nights...seriously get a different hobby.
GM WILL NOT make a 4 valve V8 to replace the LS series. They know what their customers want, and as already brought up, it the reason the LS was created for the Corvette instead of a version of the LT5.
Two corvettes, one LT5, one LS based. Bring the big wigs down and let them drive both. With nothing more than driving impressions they choose the LS for the power delivery and driveability. This is the same reason they will continue to use and develop the archaic technology so despised by some.
To offer the kind of torque and power delivery of a larger engine in a smaller DOHC engine would require one, or two, turbos, small turbos running small amounts of boost. At this point you've added HUNDREDS of pounds to the old pushrod equipped car as well as around 10k to the price.
Yes, DOHC is a very efficient (efficient means makes power, not just MPGs) design for an engine, BUT it is highly illogical for the topic at hand.
Plus we just don't like no rustangs. So any geriatrics in here who still wanna swing from the proverbial automotive nuts they love to coddle should just leave the topic alone.
06-06-2010, 06:09 PM
#109
TECH Senior Member
All these arguments have been done over and over and over again. If DOHC wasn't competitive, and the government didn't require cleaner engines than the LS series has been to date(and those emissions are already law), nobody would be advancing DOHC engines for American cars, INCLUDING General Motors... But alas, they are.
We can expect smaller engines in our future. Less cubes, that is.
If anything there will be less high strained small cubed engines (like the F20C for example) which suck more gas than a "big ole" 7L pushrod V8.
JD... Please take a moment to consider your "ricer math" argument... You've tried to use it more than once and yet, you also make the argument that DOHC engines don't have the power/torque to weight of the LS series. It that isn't "ricer" math, neither is anything else.
Let me ask you, does power/weight get you down a track faster, or power/displacement?
Is a lighter weight, physically smaller engine not beneficial to performance?
Because smaller displacement certainly is not beneficial in any way what so ever, especially when the small displaced engine is heavier and bigger.
And to the last part... I take it you're referring to the 500+ CI LSX block, correct? How cheap is that, anyway?
By the way, MARKETING never built a single engine... Not to mention the LS series is "marketed" far more than any DOHC I've heard of in the past. Just ask a general auto fan what powers the Camaro SS or the Corvette, or maybe even the full size GM trucks... Then ask them what powers the Cadillac XLR-V and see which offers the blank stare most often.
Ill post the article for you again in case you missed it the first time:
http://www.caranddriver.com/features...its_due-column
"So if the pushrod design makes such a good V-8, why does GM make a DOHC V-8 Northstar? "I'm not going to touch that one," laughs Winegarden. GM's party line is that some customers want what it calls "high-feature engines." Winegarden does admit there are some refinement benefits to the DOHC layout, but personally, I don't find the Vette's engine to be a bit unruly. "
06-06-2010, 09:15 PM
#110
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We've gotten carried away with the idea that you must either like OHV or OHC designs... That's foolish to me. I'm tired of arguing the same points. The law has been written and signed by our dimwit President... When they go into effect, Standby.
06-06-2010, 09:35 PM
#111
Oh my god, now it's turning political. Please no one reply to this.
06-06-2010, 09:40 PM
#112
Douchebag On The Tree
Not to be a nitpicking nancy, but you just did...****, so did I.
06-06-2010, 09:50 PM
#113
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As for turning political... it's been political since 1972...
06-06-2010, 10:04 PM
#114
Douchebag On The Tree
Did you know that GM makes several types of engines? I suspect you did... Did you know that most of their engines today, aside from full size pickups, are not part of the LS series? Well... If they know what their customers want, evidently most don't care if it's an LS or not.
As for turning political... it's been political since 1972...
As for turning political... it's been political since 1972...
Just in case, LS1TECH.
And just in case you still don't understand the topic at hand (i.e. the one particular engine line we are debating about) here is the very first post of this thread...with the relevant stuff highlighted for retards, of course.
Just seeing if anyone has any info on if GM will ever move to LS 4 valve V8? Ford has already made the move with the GT 500 platform and the new 5.0
All of the LS motors are very efficient and can make plenty of power, but the pushrod design has been around for decades and is basically imo old technology.
I just feel that it would be step in the right direction if they were to introduce a LS 4 valve motor.
Just looking for some of yalls opinions on this.
All of the LS motors are very efficient and can make plenty of power, but the pushrod design has been around for decades and is basically imo old technology.
I just feel that it would be step in the right direction if they were to introduce a LS 4 valve motor.
Just looking for some of yalls opinions on this.
06-06-2010, 11:30 PM
#115
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Its turned into a little dick contest now, congrats guys for contributing nothing but stupid bullshit that ruins threads and discourages people from forums all together
06-06-2010, 11:33 PM
#116
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Man... get over it already with all the silly insults. When all else fails, tell everyone it's LS1tech... We all know which site we're on. You've been here about 7mo... I don't think I need your help on this subject. 
You don't get to determine whether or not others can continue posting. If you don't like the way things are going, you may leave.
Just because it's LS1tech doesn't mean everyone and everything needs to revolve around the LS1... Millions of people would really like to see an LS based engine with 4vpc, btw. However, GM currently offers the Northstar in such a V8 configuration. Maybe they can change that name to "LS Northstar"... would that make you happy?
You don't get to determine whether or not others can continue posting. If you don't like the way things are going, you may leave.Just because it's LS1tech doesn't mean everyone and everything needs to revolve around the LS1... Millions of people would really like to see an LS based engine with 4vpc, btw. However, GM currently offers the Northstar in such a V8 configuration. Maybe they can change that name to "LS Northstar"... would that make you happy?
06-06-2010, 11:34 PM
#117
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06-06-2010, 11:53 PM
#118
Douchebag On The Tree
Man... get over it already with all the silly insults. When all else fails, tell everyone it's LS1tech... We all know which site we're on. You've been here about 7mo... I don't think I need your help on this subject. You don't get to determine whether or not others can continue posting. If you don't like the way things are going, you may leave.
Just because it's LS1tech doesn't mean everyone and everything needs to revolve around the LS1... Millions of people would really like to see an LS based engine with 4vpc, btw. However, GM currently offers the Northstar in such a V8 configuration. Maybe they can change that name to "LS Northstar"... would that make you happy?
You don't get to determine whether or not others can continue posting. If you don't like the way things are going, you may leave.Just because it's LS1tech doesn't mean everyone and everything needs to revolve around the LS1... Millions of people would really like to see an LS based engine with 4vpc, btw. However, GM currently offers the Northstar in such a V8 configuration. Maybe they can change that name to "LS Northstar"... would that make you happy?
I really don't know how to explain this any further. This thread is "Will GM make the LS series into 4V setup." The answer is "No, for reasons already pointed out"
Nowhere in this thread does anyone ask about your OHC wetdreams. So, get off that high horse, don't take the internet too seriously, and stop posting.
See what I did there? I said stop posting...that's not nice, I'm not allowed to do that....
06-06-2010, 11:57 PM
#119
Douchebag On The Tree
Just because it's LS1tech doesn't mean everyone and everything needs to revolve around the LS1... Millions of people would really like to see an LS based engine with 4vpc, btw. However, GM currently offers the Northstar in such a V8 configuration. Maybe they can change that name to "LS Northstar"... would that make you happy?
Did you know that GM makes several types of engines? I suspect you did... Did you know that most of their engines today, aside from full size pickups, are not part of the LS series? Well... If they know what their customers want, evidently most don't care if it's an LS or not.
As for turning political... it's been political since 1972...
As for turning political... it's been political since 1972...
I'm gonna need a reference to cite the millions of people that want this.
06-07-2010, 10:44 AM
#120
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The caddy 4.4 you keep trolling with is supercharged.
1. LSx engines are tiny compared to comparable power (let alone displacement) dohc engines. As such, the engineering (you know, the thing most people THINK they understand) criteria probably looked at what would fit within a given engine bay, what output characteristics, lifetime performance, service, production factors, operating costs, etc.
2. OHV engines are inherently simple, this is great news for durability. The more complex, the more room for error; you can't escape that.
3. The higher one revs an engine, the higher the stresses placed, so OHV works just fine because few people like to whiz around at 9K.
4. I have had MANY dohc powered cars, in terms of driving, they are a very different feel (they got to in order to compensate for lack of displacement).
5. Engines are merely air pumps, and for 99.98% of the population, they don't care how they get from point A to point B so long as that engine keeps working.
6. A SMART company listens to their audience... and people vote with wallets. If GM created a high displacement DOHC V8 ala 6.3 Merc, 95% of GM enthusiasts would scratch their head and balk at buying. That means wasted cash by GM.
7. And GM does offer 4 Valve V8s of 6+L displacement... it's called a Duramax, and no it doesn't use DOHC.
I beat the **** out of my vette, and it's never had a engine issue even when I execute a 3-2 accidental downshift multiple times. You can NOT do accidental downshifts in a DOHC and expect that engine to take it.
This thread has strayed entirely too far off topic, let's keep it focused on LSx architecture or similar featuring 4 valves.
I'll start.
It'd be great to offer 4 valves, you simply get more air. But for the packaging problems, why not just use forced induction? It's all the same to combustion, more air in regardless of how you do it. By going FI, you can eshew the relative losses compared to using 4Valves by just tailoring the FI to a lower rev band... and since your already higher displacement you can keep running pump gas to prolong avoiding detonation.
1. LSx engines are tiny compared to comparable power (let alone displacement) dohc engines. As such, the engineering (you know, the thing most people THINK they understand) criteria probably looked at what would fit within a given engine bay, what output characteristics, lifetime performance, service, production factors, operating costs, etc.
2. OHV engines are inherently simple, this is great news for durability. The more complex, the more room for error; you can't escape that.
3. The higher one revs an engine, the higher the stresses placed, so OHV works just fine because few people like to whiz around at 9K.
4. I have had MANY dohc powered cars, in terms of driving, they are a very different feel (they got to in order to compensate for lack of displacement).
5. Engines are merely air pumps, and for 99.98% of the population, they don't care how they get from point A to point B so long as that engine keeps working.
6. A SMART company listens to their audience... and people vote with wallets. If GM created a high displacement DOHC V8 ala 6.3 Merc, 95% of GM enthusiasts would scratch their head and balk at buying. That means wasted cash by GM.
7. And GM does offer 4 Valve V8s of 6+L displacement... it's called a Duramax, and no it doesn't use DOHC.
I beat the **** out of my vette, and it's never had a engine issue even when I execute a 3-2 accidental downshift multiple times. You can NOT do accidental downshifts in a DOHC and expect that engine to take it.
This thread has strayed entirely too far off topic, let's keep it focused on LSx architecture or similar featuring 4 valves.
I'll start.
It'd be great to offer 4 valves, you simply get more air. But for the packaging problems, why not just use forced induction? It's all the same to combustion, more air in regardless of how you do it. By going FI, you can eshew the relative losses compared to using 4Valves by just tailoring the FI to a lower rev band... and since your already higher displacement you can keep running pump gas to prolong avoiding detonation.
Last edited by OKcruising; 06-07-2010 at 10:54 AM.