Check out this new style Intake manafold!
12-14-2008, 09:59 PM
#181
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First I'd like to congratulate you on a nice looking intake. Having designed many myself, I can recognize quality work. That said, my statement about the 4-inch runner is entirely accurate and I hope that I don't get too technical here, but being an intake designer, you should know all of this math already. As I'm sure you already know the three distinct forms of ram filling associated with any intake design, we will focus on calculating the induction tract length. Using a crank-angle movement of 85 degree (basically an average between 80-90 degrees) and a constant for the speed of sound at 330m/sec (it is not actually fixed in an induction system but the calculations become pretty scary if we use acceleration), we can apply the simple formula of crank angle x speed of sound/.012 x engine speed. This will provide the runner length for optimum wave tuning (note the length includes the head port). If we use 10,000 rpm as a maximum (even most LS-based race motors run lower than this), but it will serve as an exaggerated example. Plugging 10,000 rpm into our formula, we see that the optimum runner length for maximum wave filling is just over 9 inches! If we subtract 3 inches for the head port, that still leaves us with 6 inches of intake runner length for a 10,000 rpm motor. This example of course assumes the runner diameter (or cross section) is optimized for the displacement. Your 4-inch runner is 33% too short even for a 10,000 rpm motor. What this means is that you can lengthen the runner and not lose any peak power and pick up huge gains at lower engine speeds (by lower I mean anything below 10,000 rpm). It should be obvious that I understand a thing or two about induction systems and not only from a mathematical standpoint, but from real-world testing. I have (in my literally thosands of dyno sessions) run LS motors and changed nothing more than runner length (from 20 inches down to 2 inches) to verify the math-it is accurate. Please don't talk to me about displacement or cam timing, since I know the intake opening point determines the start of the reflected wave-the induction length formula works regardless of the other variables (keeping runer cross section optimum). BTW-The reason I have not offered advice or test results to forums like these in the past is because real data seems to just **** people off. You seem sharp enough to look at this information and get something from it-others will no doubt rant and rave about how (despite the accuracy of the information) I've somehow offended a sponsor.
12-14-2008, 10:18 PM
#182
On The Tree
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First I'd like to congratulate you on a nice looking intake. Having designed many myself, I can recognize quality work. That said, my statement about the 4-inch runner is entirely accurate and I hope that I don't get too technical here, but being an intake designer, you should know all of this math already. As I'm sure you already know the three distinct forms of ram filling associated with any intake design, we will focus on calculating the induction tract length. Using a crank-angle movement of 85 degree (basically an average between 80-90 degrees) and a constant for the speed of sound at 330m/sec (it is not actually fixed in an induction system but the calculations become pretty scary if we use acceleration), we can apply the simple formula of crank angle x speed of sound/.012 x engine speed. This will provide the runner length for optimum wave tuning (note the length includes the head port). If we use 10,000 rpm as a maximum (even most LS-based race motors run lower than this), but it will serve as an exaggerated example. Plugging 10,000 rpm into our formula, we see that the optimum runner length for maximum wave filling is just over 9 inches! If we subtract 3 inches for the head port, that still leaves us with 6 inches of intake runner length for a 10,000 rpm motor. This example of course assumes the runner diameter (or cross section) is optimized for the displacement. Your 4-inch runner is 33% too short even for a 10,000 rpm motor. What this means is that you can lengthen the runner and not lose any peak power and pick up huge gains at lower engine speeds (by lower I mean anything below 10,000 rpm). It should be obvious that I understand a thing or two about induction systems and not only from a mathematical standpoint, but from real-world testing. I have (in my literally thosands of dyno sessions) run LS motors and changed nothing more than runner length (from 20 inches down to 2 inches) to verify the math-it is accurate. Please don't talk to me about displacement or cam timing, since I know the intake opening point determines the start of the reflected wave-the induction length formula works regardless of the other variables (keeping runer cross section optimum). BTW-The reason I have not offered advice or test results to forums like these in the past is because real data seems to just **** people off. You seem sharp enough to look at this information and get something from it-others will no doubt rant and rave about how (despite the accuracy of the information) I've somehow offended a sponsor.
J/K...good reading material there. Not alot of theory/knowledge gets thrown around on intake manifolds around here.
12-15-2008, 05:07 AM
#183
xram all that is grat, but when vinny takes a stock GM L76 intake off his mild 402 ci motor and puts this intake on and picks up 50 rwhp and it only lost power down below 5000 rpm, and carried the power another 1000 rpm up to the max that he was willing to spin the motor too, it tosses the mat out the window completely.
Noone that wants to put this intake cares about under 5000 rpm power, this is a RACE intake, as long as the car has enough power to pull up to the staging lanes, get the burnout going, load on and off teh trailer and come down the return road I don't give a HOOT about what happens below 5000 rpm. The car leaves at 4000 and is at 5000 withing about 5 feet of moving on the track, and lever seels below that again the entire run.
Guys road racing, aren't putting their cars below 5000 rpm unless they're slowing down for a corner, in that case again, it doesn't matter!
You can blah blah us with math all day, but we have a solid 50 hp gain already with this intake over GM's offering for the L92 heads, and I am positive that it's going to do the same thing to a fast 90, or 92, or the 100+ that they're working on.
Real world is what we care about here, not some BS math from a book.
I've read engine books over the years, and in "theory" they all seem great, until you get in the real world and put something together and try it. Hell by the "math" my car shouldn't make the power it does when looking at the max flow that an untouched fast intake has, but it beats that # all day long.
Theory is just that, theory.
Noone that wants to put this intake cares about under 5000 rpm power, this is a RACE intake, as long as the car has enough power to pull up to the staging lanes, get the burnout going, load on and off teh trailer and come down the return road I don't give a HOOT about what happens below 5000 rpm. The car leaves at 4000 and is at 5000 withing about 5 feet of moving on the track, and lever seels below that again the entire run.
Guys road racing, aren't putting their cars below 5000 rpm unless they're slowing down for a corner, in that case again, it doesn't matter!
You can blah blah us with math all day, but we have a solid 50 hp gain already with this intake over GM's offering for the L92 heads, and I am positive that it's going to do the same thing to a fast 90, or 92, or the 100+ that they're working on.
Real world is what we care about here, not some BS math from a book.
I've read engine books over the years, and in "theory" they all seem great, until you get in the real world and put something together and try it. Hell by the "math" my car shouldn't make the power it does when looking at the max flow that an untouched fast intake has, but it beats that # all day long.
Theory is just that, theory.
12-15-2008, 06:42 AM
#184
TECH Fanatic
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First I'd like to congratulate you on a nice looking intake. Having designed many myself, I can recognize quality work. That said, my statement about the 4-inch runner is entirely accurate and I hope that I don't get too technical here, but being an intake designer, you should know all of this math already. As I'm sure you already know the three distinct forms of ram filling associated with any intake design, we will focus on calculating the induction tract length. Using a crank-angle movement of 85 degree (basically an average between 80-90 degrees) and a constant for the speed of sound at 330m/sec (it is not actually fixed in an induction system but the calculations become pretty scary if we use acceleration), we can apply the simple formula of crank angle x speed of sound/.012 x engine speed. This will provide the runner length for optimum wave tuning (note the length includes the head port). If we use 10,000 rpm as a maximum (even most LS-based race motors run lower than this), but it will serve as an exaggerated example. Plugging 10,000 rpm into our formula, we see that the optimum runner length for maximum wave filling is just over 9 inches! If we subtract 3 inches for the head port, that still leaves us with 6 inches of intake runner length for a 10,000 rpm motor. This example of course assumes the runner diameter (or cross section) is optimized for the displacement. Your 4-inch runner is 33% too short even for a 10,000 rpm motor. What this means is that you can lengthen the runner and not lose any peak power and pick up huge gains at lower engine speeds (by lower I mean anything below 10,000 rpm). It should be obvious that I understand a thing or two about induction systems and not only from a mathematical standpoint, but from real-world testing. I have (in my literally thosands of dyno sessions) run LS motors and changed nothing more than runner length (from 20 inches down to 2 inches) to verify the math-it is accurate. Please don't talk to me about displacement or cam timing, since I know the intake opening point determines the start of the reflected wave-the induction length formula works regardless of the other variables (keeping runer cross section optimum). BTW-The reason I have not offered advice or test results to forums like these in the past is because real data seems to just **** people off. You seem sharp enough to look at this information and get something from it-others will no doubt rant and rave about how (despite the accuracy of the information) I've somehow offended a sponsor.
Thanks for the compliment on our manifold.
Please stop spreading false information on our manifolds power range. Since you are an 'intake designer' you probably already know that the 'head port' of a LS motor is nowhere near 3" long, maybe you made a typo, or maybe you need to do a little more research.
Vinny
Last edited by 860 Performance; 12-15-2008 at 01:31 PM.
12-15-2008, 10:27 AM
#188
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I guess you missed the part in the explanation about the theory being backed up by real back-to-back data by actually adjusting the runner length, but don't let a little thing like reality spoil your opinion. Your example does not toss math out the window-if you don't understand something, just ask. The point of the explanation is that it is possible to have all those gains you experienced plus have more area under the curve-how can you argue against that?
xram all that is grat, but when vinny takes a stock GM L76 intake off his mild 402 ci motor and puts this intake on and picks up 50 rwhp and it only lost power down below 5000 rpm, and carried the power another 1000 rpm up to the max that he was willing to spin the motor too, it tosses the mat out the window completely.
Noone that wants to put this intake cares about under 5000 rpm power, this is a RACE intake, as long as the car has enough power to pull up to the staging lanes, get the burnout going, load on and off teh trailer and come down the return road I don't give a HOOT about what happens below 5000 rpm. The car leaves at 4000 and is at 5000 withing about 5 feet of moving on the track, and lever seels below that again the entire run.
Guys road racing, aren't putting their cars below 5000 rpm unless they're slowing down for a corner, in that case again, it doesn't matter!
You can blah blah us with math all day, but we have a solid 50 hp gain already with this intake over GM's offering for the L92 heads, and I am positive that it's going to do the same thing to a fast 90, or 92, or the 100+ that they're working on.
Real world is what we care about here, not some BS math from a book.
I've read engine books over the years, and in "theory" they all seem great, until you get in the real world and put something together and try it. Hell by the "math" my car shouldn't make the power it does when looking at the max flow that an untouched fast intake has, but it beats that # all day long.
Theory is just that, theory.
Noone that wants to put this intake cares about under 5000 rpm power, this is a RACE intake, as long as the car has enough power to pull up to the staging lanes, get the burnout going, load on and off teh trailer and come down the return road I don't give a HOOT about what happens below 5000 rpm. The car leaves at 4000 and is at 5000 withing about 5 feet of moving on the track, and lever seels below that again the entire run.
Guys road racing, aren't putting their cars below 5000 rpm unless they're slowing down for a corner, in that case again, it doesn't matter!
You can blah blah us with math all day, but we have a solid 50 hp gain already with this intake over GM's offering for the L92 heads, and I am positive that it's going to do the same thing to a fast 90, or 92, or the 100+ that they're working on.
Real world is what we care about here, not some BS math from a book.
I've read engine books over the years, and in "theory" they all seem great, until you get in the real world and put something together and try it. Hell by the "math" my car shouldn't make the power it does when looking at the max flow that an untouched fast intake has, but it beats that # all day long.
Theory is just that, theory.
12-15-2008, 03:19 PM
#193
I guess you missed the part in the explanation about the theory being backed up by real back-to-back data by actually adjusting the runner length, but don't let a little thing like reality spoil your opinion. Your example does not toss math out the window-if you don't understand something, just ask. The point of the explanation is that it is possible to have all those gains you experienced plus have more area under the curve-how can you argue against that?
12-15-2008, 03:55 PM
#194
Here's the deal, we don't have the numbers yet on this intake but I hope to see them first hand vs a Vengeance ported FAST 90 on top of a 427 w/ AFR 225's on it. We are going to spin it to atleast 7K. Then we will know if it is better or not for what US RACERS need. The fact of the matter is that there isn't another intake of similar design within $1K of this thing.
Subscribing to this test you speak of.
12-16-2008, 08:27 AM
#200
Looks great Vinny. Now, just get one for me to slap on the car already!
I love the fact that I can get this thing with just the hookup for the map sensor, and don't have to bother with the caps/plugs for the evap, pcv and the brake booster. makes the whole deal alot easier.
I love the fact that I can get this thing with just the hookup for the map sensor, and don't have to bother with the caps/plugs for the evap, pcv and the brake booster. makes the whole deal alot easier.