Talk about cheaply turbo-ing a 5sfe, BADDDDDDD Options

[x_itchy_b_x]

at least its a 5th gen owner.

[celicaST]

ok ive thought about this, and i actually think that a 30watt motor could provide a benefit. not by providing boost (although it will provide a miniscule amount), but by eliminating the vaccuum. ok with my 1.8 liter 7a, it will pump around 191 cfm at 6000rpm as i already calculated. the eturbo i sas for sale advertised 250 cfm, which i assume to be correct at a low pressure gradient. like i said, it will create a pressure gradient because of the excess flow, however it will be very small. as ill say again, 30 watts isnt enough power to create significant boost obviously. what i didnt take into account is that typically the pressure in the intake manifold is about around 1psi or more less than atmospheric due to flow restriction in the intake. so, as long as the motor is powerful enough to flow more air through the filter than the engine requires, it SHOULD result in a slight performance gain.

and FAQ, i have to disagree. if a proper electric setup was mass-produced, it could be cheaper or at least similarly priced (only difference really would be etubo instead of turbo, and a high discharge alternator instead of custom exhaust manifold/downpipe), and it would be a little easier to install (no exhaust modification, oil lines to hookup). yes i know it wont be as thermodynamically efficient as a turbo, but it should be somewhat comparable to a supercharger. main advantages again would be installation, controlability, reliability. remember, the smaller motor the easier this would be. my 1.8 7a with a 300amp alt is still on the lower end of performance (although it would work). and with a 2.2 5s, your looking at an even higher power alt/motor required. time to crack open the books and do some hard calculations

[jgreening]

ok ive thought about this, and i actually think that a 30watt motor could provide a benefit. not by providing boost (although it will provide a miniscule amount), but by eliminating the vaccuum. ok with my 1.8 liter 7a, it will pump around 191 cfm at 6000rpm as i already calculated. the eturbo i sas for sale advertised 250 cfm, which i assume to be correct at a low pressure gradient. like i said, it will create a pressure gradient because of the excess flow, however it will be very small. as ill say again, 30 watts isnt enough power to create significant boost obviously. what i didnt take into account is that typically the pressure in the intake manifold is about around 1psi or more less than atmospheric due to flow restriction in the intake. so, as long as the motor is powerful enough to flow more air through the filter than the engine requires, it SHOULD result in a slight performance gain.

and FAQ, i have to disagree. if a proper electric setup was mass-produced, it could be cheaper or at least similarly priced (only difference really would be etubo instead of turbo, and a high discharge alternator instead of custom exhaust manifold/downpipe), and it would be a little easier to install (no exhaust modification, oil lines to hookup). yes i know it wont be as thermodynamically efficient as a turbo, but it should be somewhat comparable to a supercharger. main advantages again would be installation, controlability, reliability. remember, the smaller motor the easier this would be. my 1.8 7a with a 300amp alt is still on the lower end of performance (although it would work). and with a 2.2 5s, your looking at an even higher power alt/motor required. time to crack open the books and do some hard calculations

Please explain how the reduction of the vacuum reading (to something less than boost) increases performance. I always understood that at vacuum or 0 the combustion chambers are getting the same air and fuel and flow. Are you saying this is incorrect?

[celicaST]

ok ive thought about this, and i actually think that a 30watt motor could provide a benefit. not by providing boost (although it will provide a miniscule amount), but by eliminating the vaccuum. ok with my 1.8 liter 7a, it will pump around 191 cfm at 6000rpm as i already calculated. the eturbo i sas for sale advertised 250 cfm, which i assume to be correct at a low pressure gradient. like i said, it will create a pressure gradient because of the excess flow, however it will be very small. as ill say again, 30 watts isnt enough power to create significant boost obviously. what i didnt take into account is that typically the pressure in the intake manifold is about around 1psi or more less than atmospheric due to flow restriction in the intake. so, as long as the motor is powerful enough to flow more air through the filter than the engine requires, it SHOULD result in a slight performance gain.

and FAQ, i have to disagree. if a proper electric setup was mass-produced, it could be cheaper or at least similarly priced (only difference really would be etubo instead of turbo, and a high discharge alternator instead of custom exhaust manifold/downpipe), and it would be a little easier to install (no exhaust modification, oil lines to hookup). yes i know it wont be as thermodynamically efficient as a turbo, but it should be somewhat comparable to a supercharger. main advantages again would be installation, controlability, reliability. remember, the smaller motor the easier this would be. my 1.8 7a with a 300amp alt is still on the lower end of performance (although it would work). and with a 2.2 5s, your looking at an even higher power alt/motor required. time to crack open the books and do some hard calculations

Please explain how the reduction of the vacuum reading (to something less than boost) increases performance. I always understood that at vacuum or 0 the combustion chambers are getting the same air and fuel and flow. Are you saying this is incorrect?

well im sure youre aware that the mechanics of ICE's is extremely complex. NA engines are engineered to maximize the air mass enclosed in the cylinder after the intake valve closes. the timing of the intake valve is tuned to take maximum advantage of the phenomenon where the intake charge acquires a slight pressure to to rapid change in its velocity. this couples with the vacuum created by the pulse of exiting exhaust gases (exhaust scavenging) can actually create hyperbaric conditions in the chamber at certain speeds. now im not entirely sure that eliminating the vacuum would be benefitial, but my gut feeling says it would (i see no reason why it shouldnt trap more air per stroke), and what the hell, it couldnt hurt

This post has been edited by celicaST: Feb 10, 2006 - 6:31 PM