LS7 intake vs carb style.which flows better?
12-27-2007, 12:46 PM
#41
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Sheet metal intakes are nice (but cashy), and give you the best of both worlds, like the LTx intake.
GMPP is the only game in town for LS7 and L92 carb manifolds at this time, and both are single plane.
GMPP is the only game in town for LS7 and L92 carb manifolds at this time, and both are single plane.
12-27-2007, 01:05 PM
#42
Interesting opinions in here, but I dont see any facts or graphs to prove anything. Just a lot of conjecture. An LS7 intake is $345. Isnt that Beck like $2500? Mamo did some testing and his results indicated nothing good for the VicJr except at hi rpms. It isnt just the cam selection governing the torque and rpms arent soley determined by airlfow.
I am very interested in this subject and thats why I am commenting. Konnie the goat, what makes your opinion more informed than say Tony Mamo's? Why should I believe you over him? Whats your experience level ? No disprespect intended.
All results I have seen showed poorly. Even the sheetmetal intake did not outshine anything for $3000. SDPC, AFR all looked at the results and commnetd on this.
I am very interested in this subject and thats why I am commenting. Konnie the goat, what makes your opinion more informed than say Tony Mamo's? Why should I believe you over him? Whats your experience level ? No disprespect intended.
All results I have seen showed poorly. Even the sheetmetal intake did not outshine anything for $3000. SDPC, AFR all looked at the results and commnetd on this.
Last edited by 99blancoSS; 12-27-2007 at 01:39 PM.
12-27-2007, 05:43 PM
#43
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99BlancoSS, this thread started with a simple question, which one flows better. Well, the carb manifolds do outflow the stock style manifolds, by a large margin. Then we had to get into the technical reasons why we arent seeing the gains that the extra air should grant us.
Yes, a single plane carb manifold shines brightest at High RPMs. Even on a carb'd engine, that has always been the case, so to see the same on an EFI engine is exactly what you'd expect. As far as i know, there is only one dual plane manifold, and its for LS1/2/6 cathedral port heads.
The scope of testing and experience on these motors NA is damned limited. FI guys were the first to jump on them. NA guys still hump the FAST like its the head cheerleader in high school. While I am not going to say that every engine will perform better with a carb manifold (and matching heads and cam), many will. Lets face it, one can build a more powerful Gen2 motor with inferior heads for much cheaper than a LS motor. The reason is the manifold, and the years of making cams that take advantage of the pulsing.
As far as my experience, its honestly limited. i have a few years of Mech Eng school under my belt, but got tired of the lack of hands on, so i switched to full on auto tech. Which is why im heavy in theory. Well, its not so much theory, as proven science. Fluid dynamics covers the way pulsing affects flow. I apologize for the lack of pretty graphs, but really they mean ****. When I finish my build, I will of course post the dyno graphs, both engine and chassis, but thats a few months off still. And even those wont show anything shocking, other than I have a nice wide powerband. So take my words based on that. I am a nobody in this field (for now, hopefully), and a relative noob, but what I'm saying isnt. It's proven science, and is well known by the people who originally design this stuff.
Honestly, theres no good reason to take my word over anyone elses. This is not a right vs wrong subject, especially at this early stage of carb manifolds on LS engines. Any data, is good data, even if it says the manifold is detrimental on a given combo. Im sure Mr. Mamo has way more practical experience than I do, and im not familiar with his formal education, nor do I care. Even a high school drop out can run a good quality accurate scientific test. And test results speak. But I've also not seen the scope of his testing, to comment on how it was done. The GMHTP article on the subject was crap, IMO, almost completely ignoring the fact that these parts work as a system. But, I view it as an incomplete test, more than a poor one. I would hope that they would get a stack of cams, and start swaping them out. I doubt they will.
Id say from this thread that there is good interest in this topic. As there should be, in theory, this is easy power. We just need more testing to prove it. And we'll figure this out. Either as hobbyists, or someone of the corporate side of things. Just takes time.
Yes, a single plane carb manifold shines brightest at High RPMs. Even on a carb'd engine, that has always been the case, so to see the same on an EFI engine is exactly what you'd expect. As far as i know, there is only one dual plane manifold, and its for LS1/2/6 cathedral port heads.
The scope of testing and experience on these motors NA is damned limited. FI guys were the first to jump on them. NA guys still hump the FAST like its the head cheerleader in high school. While I am not going to say that every engine will perform better with a carb manifold (and matching heads and cam), many will. Lets face it, one can build a more powerful Gen2 motor with inferior heads for much cheaper than a LS motor. The reason is the manifold, and the years of making cams that take advantage of the pulsing.
As far as my experience, its honestly limited. i have a few years of Mech Eng school under my belt, but got tired of the lack of hands on, so i switched to full on auto tech. Which is why im heavy in theory. Well, its not so much theory, as proven science. Fluid dynamics covers the way pulsing affects flow. I apologize for the lack of pretty graphs, but really they mean ****. When I finish my build, I will of course post the dyno graphs, both engine and chassis, but thats a few months off still. And even those wont show anything shocking, other than I have a nice wide powerband. So take my words based on that. I am a nobody in this field (for now, hopefully), and a relative noob, but what I'm saying isnt. It's proven science, and is well known by the people who originally design this stuff.
Honestly, theres no good reason to take my word over anyone elses. This is not a right vs wrong subject, especially at this early stage of carb manifolds on LS engines. Any data, is good data, even if it says the manifold is detrimental on a given combo. Im sure Mr. Mamo has way more practical experience than I do, and im not familiar with his formal education, nor do I care. Even a high school drop out can run a good quality accurate scientific test. And test results speak. But I've also not seen the scope of his testing, to comment on how it was done. The GMHTP article on the subject was crap, IMO, almost completely ignoring the fact that these parts work as a system. But, I view it as an incomplete test, more than a poor one. I would hope that they would get a stack of cams, and start swaping them out. I doubt they will.
Id say from this thread that there is good interest in this topic. As there should be, in theory, this is easy power. We just need more testing to prove it. And we'll figure this out. Either as hobbyists, or someone of the corporate side of things. Just takes time.
12-27-2007, 07:41 PM
#44
So your a self pro-claimed expert. Ok, I'm right there with ya. Same here.
I have to go with Mamo though and his extensive work in the field. The micro physics of it are beyond me, I just dont want to get down to that level but I will trust a true expert in the field. If your not familiar with Tony Mamo he is AFR's rep here. An industry recognized expert in the area of air flow.
I have to go with Mamo though and his extensive work in the field. The micro physics of it are beyond me, I just dont want to get down to that level but I will trust a true expert in the field. If your not familiar with Tony Mamo he is AFR's rep here. An industry recognized expert in the area of air flow.
12-27-2007, 10:58 PM
#45
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Naw, I dont consider myself to be an expert. I just know the physics behind how this area works. Applying it is another matter, and that where we seem to be getting hung up.
I can see why you trust Tony's opinion and tests, I would too. But again, Id be trusting them in same way i trust GMHTP's tests, as valuable, yet incomplete. AFR makes some of the best heads on the market, but thats what they do, make heads. Cams and intakes arent their thing, so they arent going to spend a bunch of resources in those areas.
I'd love for Tony to come in here and share his thoughts, but I feel that the answer to this is going to come from high end shops, and companies like Edelbrock that have the parts, resources, and motivation to develop this for us. I'd say within a year or so, Performer or Vic JR type top end kits will be available for easy purchase just as they are for older SBC's.
I can see why you trust Tony's opinion and tests, I would too. But again, Id be trusting them in same way i trust GMHTP's tests, as valuable, yet incomplete. AFR makes some of the best heads on the market, but thats what they do, make heads. Cams and intakes arent their thing, so they arent going to spend a bunch of resources in those areas.
I'd love for Tony to come in here and share his thoughts, but I feel that the answer to this is going to come from high end shops, and companies like Edelbrock that have the parts, resources, and motivation to develop this for us. I'd say within a year or so, Performer or Vic JR type top end kits will be available for easy purchase just as they are for older SBC's.
12-28-2007, 02:26 AM
#46
Well, sorry guys, but I'm not going to be the guy who can give you dyno results for a sheet metal carb intake. Just not in the budget. This build is only happening because of me saving money while I'm deployed. I've got nearly everything I need with only a few parts to go, but my builder said he's got some 1 7/8 headers he'll let me test with to see the difference. I wish I had deep pockets.
