intake manifold design?
04-14-2006, 06:38 PM
#21
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Re: intake manifold design?
Originally Posted by boost_guy
Velocity stacks will probably not improve performance on a forced incduction engine. They are mainly used in NA applications, because the air in the center of the plenum moves faster than the air near the walls of the plenum, and moving the runner inlet toward the center of the plenum will increase velocity in the runners. This is fine when the air is being drawn into the engine. In a forced induction application they are just going to be in the way, causing turbulence and most likely hurting overall power. A nice flat bottom with radiused inlets would work nicely.
04-14-2006, 07:09 PM
#22
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Re: intake manifold design?
Originally Posted by Snafubmx234
The LS1 uses a plastic intake manifold. I think if you added some velocity stacks, that ---- would be hot.
04-14-2006, 08:05 PM
#23
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Re: intake manifold design?
Originally Posted by boost_guy
Velocity stacks will probably not improve performance on a forced incduction engine. They are mainly used in NA applications, because the air in the center of the plenum moves faster than the air near the walls of the plenum, and moving the runner inlet toward the center of the plenum will increase velocity in the runners. This is fine when the air is being drawn into the engine. In a forced induction application they are just going to be in the way, causing turbulence and most likely hurting overall power. A nice flat bottom with radiused inlets would work nicely.
N/A engines don't suck air in, air is being forced in by atmospheric pressure.
04-14-2006, 08:14 PM
#24
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Re: intake manifold design?
Originally Posted by krustindumm
Boosted engines still flow air in the same way, high to low pressure. I believe that it will be at least as important, if not more important, because the air will be higher desnity and the pressure drop will be higher, so flow rate will be higher. THat would cause even more turbulance than on a naturally aspirated engine.
N/A engines don't suck air in, air is being forced in by atmospheric pressure.
N/A engines don't suck air in, air is being forced in by atmospheric pressure.
or better yet where the ---- do you think vaccum comes from for opening your BOV? if a cylinder didnt pull in air then a BOV would never work....... so hence whhy dont ya shuve your dick in your cold air intake and test out jizz injection
yes any empty space is filled by atmospheric pressure, but in terms of a motor, i believe you are wrong
04-14-2006, 08:29 PM
#26
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Re: intake manifold design?
https://www.homemadeturbo.com/forum/...?topic=59093.0
http://full-race.com/catalog/product...roducts_id=477
the top link isnt much of stacks but stacks none the less \
heres a link showing how to make sweet stacks if anyone is interested
http://forums.vwvortex.com/zerothread?id=2517182
but velocity stacks are oviously not going to hurt if full race is putting them in their manifold, im not in love with the company or think their the greatest but still, they have top of the line ----
http://full-race.com/catalog/product...roducts_id=477
the top link isnt much of stacks but stacks none the less \
heres a link showing how to make sweet stacks if anyone is interested
http://forums.vwvortex.com/zerothread?id=2517182
but velocity stacks are oviously not going to hurt if full race is putting them in their manifold, im not in love with the company or think their the greatest but still, they have top of the line ----
04-14-2006, 08:42 PM
#27
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Re: intake manifold design?
Ok those are different than what I was picturing. When I think velocity stack I was thinking of the runner extending into the plenum a few inches, then having the bellmouth. The radiused inlet on the bottom of the plenum was what I was saying would a be a better way to do it.
04-15-2006, 12:26 AM
#30
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Re: intake manifold design?
i think your best bet is to start off going with a proven design and making your mani close to that. there are other things to consider besides air flow characteristics when building your manifold- most of which i don't have a clue of. what is your goal for power? what other modifications do you have? how big is your tb? what psi are you running? do you plan to keep your iacv?...
as for the velocity stack debate... has anyone had a chance to look inside a champ car cosworth intake manifold? those velocity stacks stick quite far into the plenum, almost to the roof. these engines are boosted, mind you they are only running 2psi and 6psi on "push to pass", but the stacks are very unique. i made up some stacks for a couple intake manifolds that i was planning on building. i will probably still use them but i know i can make something that is much better flowing after having seen the design of the stacks on the cosworth engine.
as for thermal soaking properties of your "composite" manifold, if the hondata gasket is effective, why not just pick one of those up and make the whole intake manifold out of one material? phenolic is probably the material they are using for their gaskets to prevent heat transfer, atleast that is what i'd make a gasket out of. i'd try to stay away from using two different materials just to save on headaches down the road if it isn't built properly. i'm not saying it can't be done because it is done and very effectively so. but it is hard to compare a homebuilt garage racer to a sponsored team of highly qualified engineers.
i have a lot of (borrowed) ideas that i'd like to do some r&d with in building a good race manifold for boost and apply it on a honda but i just don't have the time to do it. i'm sure in the next year or so i may just get the chance to apply a couple of them atleast... unless someone contacts me and is willing to pay me enough to cover my mortgage to experiment on their drag car i'll just have to wait to experiment on my own car.
as for the velocity stack debate... has anyone had a chance to look inside a champ car cosworth intake manifold? those velocity stacks stick quite far into the plenum, almost to the roof. these engines are boosted, mind you they are only running 2psi and 6psi on "push to pass", but the stacks are very unique. i made up some stacks for a couple intake manifolds that i was planning on building. i will probably still use them but i know i can make something that is much better flowing after having seen the design of the stacks on the cosworth engine.
as for thermal soaking properties of your "composite" manifold, if the hondata gasket is effective, why not just pick one of those up and make the whole intake manifold out of one material? phenolic is probably the material they are using for their gaskets to prevent heat transfer, atleast that is what i'd make a gasket out of. i'd try to stay away from using two different materials just to save on headaches down the road if it isn't built properly. i'm not saying it can't be done because it is done and very effectively so. but it is hard to compare a homebuilt garage racer to a sponsored team of highly qualified engineers.
i have a lot of (borrowed) ideas that i'd like to do some r&d with in building a good race manifold for boost and apply it on a honda but i just don't have the time to do it. i'm sure in the next year or so i may just get the chance to apply a couple of them atleast... unless someone contacts me and is willing to pay me enough to cover my mortgage to experiment on their drag car i'll just have to wait to experiment on my own car.
