slvrstreak's latest build thread
#251
here's my thought process (which is likely flawed)
we all know one 2" pipe draws in more than two 1" pipes but bare with me here
these are completely irrelevant numbers only used for illustrative purposes
the intake takes in say 500g; the short ram air setup currently used allows the max airflow of 500g with a single short 2" tube
however after lengthening said tube the airflow will fall to say ~400g because the air has to travel a further distance through additional contours
but if you use two long 2" tubes the airflow should be back up to its maximum potential
I realize this is completely dumbed down and may not be entirely accurate but, the process seems to make sense in my mind
as I said I plan on making both anyway to actually be able to compare the difference in air temp, flow, turbulance, etc
we all know one 2" pipe draws in more than two 1" pipes but bare with me here
these are completely irrelevant numbers only used for illustrative purposes
the intake takes in say 500g; the short ram air setup currently used allows the max airflow of 500g with a single short 2" tube
however after lengthening said tube the airflow will fall to say ~400g because the air has to travel a further distance through additional contours
but if you use two long 2" tubes the airflow should be back up to its maximum potential
I realize this is completely dumbed down and may not be entirely accurate but, the process seems to make sense in my mind
as I said I plan on making both anyway to actually be able to compare the difference in air temp, flow, turbulance, etc
#253
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Isn't a longer intake more beneficial to lower RPM because the air has more time to build up velocity? The higher the RPM, the shorter the intake should be because the length then starts to become a restriction. Of course, this is all still based on naturally aspirated mechanics. Add a turbine to the equation and I'm pretty sure you just need to supply the cold side as much immediate air as possible, as the turbine will pull in as much air as it's allowed to. As long as the flow across the MAF is stable, the less restriction and the shorter the intake, the better.
That being said, have you considered switching to a MAP based ECU at some point?
That being said, have you considered switching to a MAP based ECU at some point?
#254
thats why boring out the TB made such a difference imo
Isn't a longer intake more beneficial to lower RPM because the air has more time to build up velocity? The higher the RPM, the shorter the intake should be because the length then starts to become a restriction. Of course, this is all still based on naturally aspirated mechanics. Add a turbine to the equation and I'm pretty sure you just need to supply the cold side as much immediate air as possible, as the turbine will pull in as much air as it's allowed to. As long as the flow across the MAF is stable, the less restriction and the shorter the intake, the better.
That being said, have you considered switching to a MAP based ECU at some point?
That being said, have you considered switching to a MAP based ECU at some point?
cooler air at the cost of flow but, thats where I was trying to compensate with dual intakes
in theory a larger panel filter/tubing would likely do the same thing
as much as I'd like to I don't have that deep of pockets and everyone says it will always cause problems
Last edited by slvrstreak; 09-10-2013 at 10:18 AM.
#255
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Isn't a longer intake more beneficial to lower RPM because the air has more time to build up velocity? The higher the RPM, the shorter the intake should be because the length then starts to become a restriction. Of course, this is all still based on naturally aspirated mechanics. Add a turbine to the equation and I'm pretty sure you just need to supply the cold side as much immediate air as possible, as the turbine will pull in as much air as it's allowed to. As long as the flow across the MAF is stable, the less restriction and the shorter the intake, the better.
That being said, have you considered switching to a MAP based ECU at some point?
That being said, have you considered switching to a MAP based ECU at some point?
slvr, if you want to test, just come up with some mock up setups and measure your maf readings. If you really want to get it right, you'd want an intake that pulls the exact amount of air that you can flow. That's a lot of leg work and trial and error though.
#256
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your intake might not be as much of a limiting factor as your maf. They can only meter so much air. If you start flowing more air than it can meter, you're gonna have a bad time.
#257
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Agreed. In B@W I advocated an intake like the Dodge Viper has stock. Short, runs straight to an box right behind an opening in the hood that gets moderately pressurize from forward speed.
Would need to pressure map the hood to make sure he isn't putting it in a low pressure zone of the hood. Neutral pressure is the lowest it should be, to avoid making the turbine work harder than it has to. The highest the pressure here, the less work is imposed on the turbine. The Viper's might actually be in a low pressure zone, looking at where it is, as low pressure forms right behind the leading edge of the hood, increasing the pressure as it moves backwards, to high pressure at the base of the windshield (where Grand Am RX-8 intakes pull from)
Would need to pressure map the hood to make sure he isn't putting it in a low pressure zone of the hood. Neutral pressure is the lowest it should be, to avoid making the turbine work harder than it has to. The highest the pressure here, the less work is imposed on the turbine. The Viper's might actually be in a low pressure zone, looking at where it is, as low pressure forms right behind the leading edge of the hood, increasing the pressure as it moves backwards, to high pressure at the base of the windshield (where Grand Am RX-8 intakes pull from)
#258
calling Cam now to see if they know the optimum airflow for the SC
I imagine the limiting factor is going to be the TB though
anybody know how many g/sec the stock TB is supposed to be able to handle?
I've got a series of tests I want to run concerning different intake setups that will really clear things up...just throwing everything out there to see what everyone's hypothesis is
like you said the low end isn't as important but, it does help acceleration and throttle response
I imagine the limiting factor is going to be the TB though
anybody know how many g/sec the stock TB is supposed to be able to handle?
I've got a series of tests I want to run concerning different intake setups that will really clear things up...just throwing everything out there to see what everyone's hypothesis is
like you said the low end isn't as important but, it does help acceleration and throttle response
#259
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calling Cam now to see if they know the optimum airflow for the SC
I imagine the limiting factor is going to be the TB though
anybody know how many g/sec the stock TB is supposed to be able to handle?
I've got a series of tests I want to run concerning different intake setups that will really clear things up...just throwing everything out there to see what everyone's hypothesis is
like you said the low end isn't as important but, it does help acceleration and throttle response
I imagine the limiting factor is going to be the TB though
anybody know how many g/sec the stock TB is supposed to be able to handle?
I've got a series of tests I want to run concerning different intake setups that will really clear things up...just throwing everything out there to see what everyone's hypothesis is
like you said the low end isn't as important but, it does help acceleration and throttle response
The stock DBW throttle has issues though Mine seemed to be possessed at times...the ECU controls opening based on some parameters ( load?, temp? god knows what else) and can decide to close a bit on it's own. That has caused me more problems than enough....and we could see it on the dyno...almost like a limiter. Took the DBW throttle out and built a cable throttle and have loved it...car made more power with basically the same size throttle body..and the throttle response is much crisper. I used a throttle body off a Star Mazda race car...and the actuator lever is quite short...not much pedal travel from full off to full on
#263
rev it up
I have been looking at experimenting with my intake. My current intake is quite long and I seem to get a slight lag at low RPM. I also have a small filter which requires regular cleaning due to the lack of space behind the bumper bar.
I was thinking of creating a sealed box in the stock position and adding a large conical filter. I would also maintain the pipe behind the bumper bar to provide fresh air to the filter.
I was thinking of creating a sealed box in the stock position and adding a large conical filter. I would also maintain the pipe behind the bumper bar to provide fresh air to the filter.
#265
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The cost will largely depend on the development, target audience, and the feature list. My Hydra for my MSM ran me $2k, including $500 worth of sensors and supporting hardware. OMP control and injector staging are the two more uncommon features that you would need, though injector staging still isn't that rare and a PWM output could handle the OMP. The other factory ECU stuff that deals with intake valving and such isn't really a concern for you.
A full race Bosch ECU would run you that $20k, but I'd be surprised if there wasn't something far cheaper that would be entirely sufficient.
Be wary of negative opinions as much as positive ones, both are usually incomplete. Software for ECUs is always progressing, and plenty of the negative opinions out there on specific products are from people that dealt with a buggy version once, and are incapable of recognizing that later versions might actually be better. Hydra 2.1 and older was horrific, for example. Even as late as 2.6 was troublesome. 2.7 is really really solid. Still, people in the Miata community will rail against Hydra of any version as complete crap because of their 2.1 experience.
I expect that nearly every ECU out there follows a similar line of development. Really the same thing with flashing software like MazdaEdit. Growing pains are part of any software.
A full race Bosch ECU would run you that $20k, but I'd be surprised if there wasn't something far cheaper that would be entirely sufficient.
Be wary of negative opinions as much as positive ones, both are usually incomplete. Software for ECUs is always progressing, and plenty of the negative opinions out there on specific products are from people that dealt with a buggy version once, and are incapable of recognizing that later versions might actually be better. Hydra 2.1 and older was horrific, for example. Even as late as 2.6 was troublesome. 2.7 is really really solid. Still, people in the Miata community will rail against Hydra of any version as complete crap because of their 2.1 experience.
I expect that nearly every ECU out there follows a similar line of development. Really the same thing with flashing software like MazdaEdit. Growing pains are part of any software.
#266
I seriously doubt that the throttle body will be a problem with flow. I have crammed over 480hp through it without an issue.
The stock DBW throttle has issues though Mine seemed to be possessed at times...the ECU controls opening based on some parameters ( load?, temp? god knows what else) and can decide to close a bit on it's own. That has caused me more problems than enough....and we could see it on the dyno...almost like a limiter. Took the DBW throttle out and built a cable throttle and have loved it...car made more power with basically the same size throttle body..and the throttle response is much crisper. I used a throttle body off a Star Mazda race car...and the actuator lever is quite short...not much pedal travel from full off to full on
The stock DBW throttle has issues though Mine seemed to be possessed at times...the ECU controls opening based on some parameters ( load?, temp? god knows what else) and can decide to close a bit on it's own. That has caused me more problems than enough....and we could see it on the dyno...almost like a limiter. Took the DBW throttle out and built a cable throttle and have loved it...car made more power with basically the same size throttle body..and the throttle response is much crisper. I used a throttle body off a Star Mazda race car...and the actuator lever is quite short...not much pedal travel from full off to full on
did you try just leaving the SSV open all the time?
#267
The Hydra is a toy, not a real ecu.
Slvr just invest $6k in a motec and supporting sensors, lol. It should be enough...
Oh and screw having just 1 throttle body on a race engine. Start your build from the manifold.
Slvr just invest $6k in a motec and supporting sensors, lol. It should be enough...
Oh and screw having just 1 throttle body on a race engine. Start your build from the manifold.
#269
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I have been looking at experimenting with my intake. My current intake is quite long and I seem to get a slight lag at low RPM. I also have a small filter which requires regular cleaning due to the lack of space behind the bumper bar.
I was thinking of creating a sealed box in the stock position and adding a large conical filter. I would also maintain the pipe behind the bumper bar to provide fresh air to the filter.
I was thinking of creating a sealed box in the stock position and adding a large conical filter. I would also maintain the pipe behind the bumper bar to provide fresh air to the filter.
#270
rev it up
#271
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The typical polystyrene is not very strong or durable, but it's usually good to almost 300F/150C. Make it out of thin aluminum and then use dense foam to insulate it. They sell a nice dense foam that is very tough at home improvement stores here in the USA.
#272
I think skc was saying he would use poly to make a box to see if there were any results and then build one out of alloy if he got the desired results like the one above.
Guessing you make that yourself team? looks like good craftsmanship.
Wish I knew how to weld.
Guessing you make that yourself team? looks like good craftsmanship.
Wish I knew how to weld.
#274
Nice, I wonder how strong the DIY carbon fibre is as you don't have the last process with the compressed air in a sealed bag. Probably strong enough for simple air boxes tho.
The german kosinonegg (mind my spelling) has over 400 cf parts YouTube it it's awesome.
The german kosinonegg (mind my spelling) has over 400 cf parts YouTube it it's awesome.