[AmuroRay]

Off topic, likely an engineering related question - but why does the N55s head flow so poorly? It flows the same as the M20, and less than that of the M5x series

[n55david]

Wow, those are pretty garbage numbers tbh

[AmuroRay]

Originally Posted by Phantom10R

Wow, those are pretty garbage numbers tbh

Right? Wouldn’t it be easier to use a better head, and you would get better response and power from the same size turbo? Or am I wrong?

[n55david]

Well response would be great as is.. but for power, horrible by todays standard. Id be curious to know what the s55 head is like and then the numbers for the b58 and new s58

[bqik]

Originally Posted by Phantom10R

Well response would be great as is.. but for power, horrible by todays standard. Id be curious to know what the s55 head is like and then the numbers for the b58 and new s58

http://www.***********.com/content.p...-cylinder-head

put [Admin Notified] where the ***** are and you will find head b58 info

you know, why do you need to design a head with great flow if boost is what matters?

NA would be another thing but a Turbo makes things easier or less costly.

imagine the N55 with the S54B32 head.

[n55david]

Originally Posted by bqik

http://www.***********.com/content.p...-cylinder-head

put [Admin Notified] where the ***** are and you will find head b58 info

you know, why do you need to design a head with great flow if boost is what matters?

NA would be another thing but a Turbo makes things easier or less costly.

imagine the N55 with the S54B32 head.

Air volume is what matters. Boost is restriction. With a higher flowing head you can get the same volume of air with less boost levels... meaning, you could make the same or more power with less boost levels.. like for example, you could make 400hp with 12psi instead of 15psi, etc.

[T_H_O_M_A_S]

this thread is useless without dyno numbers of the same engine with the same fuel on the same dyno at the same ambient conditions , with stock and after that a ported head

i bet the differences are going to be negligible

[AmuroRay]

Originally Posted by T_H_O_M_A_S

this thread is useless without dyno numbers of the same engine with the same fuel on the same dyno at the same ambient conditions , with stock and after that a ported head

i bet the differences are going to be negligible

Dyno numbers for what? I’m not selling anything, I’m asking why the head’s flow is so poor.

[doodlebro]

Originally Posted by bqik

http://www.***********.com/content.p...-cylinder-head

put [Admin Notified] where the ***** are and you will find head b58 info

you know, why do you need to design a head with great flow if boost is what matters?

NA would be another thing but a Turbo makes things easier or less costly.

imagine the N55 with the S54B32 head.

I'm used to the asterisks, but "Admin notified"?

This board is trash. It's 2019, why are we not able to share links easily?

[T_H_O_M_A_S]

Originally Posted by AmuroRay

Dyno numbers for what? I’m not selling anything, I’m asking why the head’s flow is so poor.

didnt say you are selling anything . but the percentage differences you show in the flow chart wont be the same if you would put the same head and ported one on a dyno

i would like to see how they come up with such a graph anyway
how they make those measurements .

[AmuroRay]

Originally Posted by T_H_O_M_A_S

didnt say you are selling anything . but the percentage differences you show in the flow chart wont be the same if you would put the same head and ported one on a dyno

i would like to see how they come up with such a graph anyway
how they make those measurements .

It’s a flow bench. The graph shows airflow are different valve lifts. I’ll see if I can find a dyno.

[AmuroRay]

Dyno.

[T_H_O_M_A_S]

it looks they are running two different maps ?
why would it go 300 rpm extra ?
but its only a minimal topend improvement for a very expensive job .