B16 vs B18

Test de dos colectores para el B16A1 del 4a negro.

260CFM un colector de admision de B16A2 y 280CFM de un colector B18  spec-R.

Falta trabajarlos para ver hasta cuanto estiran en CFM estos dos colectores.

El B18 es unos 20-25mm mas corto que el B16.

B16 head

Ultimo b16a2, con unos 295cfm en admision .

B16A2

probando detalles nuevos en una culata b16a2.  he conseguido ganar algo mas de flujo, pasando de los 290CFM.

B16>=K20A2

otro B16 superando en flujo a un K20A2, con un maximo de 290CFM. No esta mal para el B con valvula mas pequeña. me gustaria probar a dejar este acabado, ayuda a la atomizacion del fuel, o eso dice alguno, pero no tengo medios para comprobarlo. Tendre que hacerlo en alguna culata mia a ver que sucede.

finished B16

just to compare, this is how i receveid the head.

more b16

more advances on this head. installed bronze valve guides, new valve seats...
i erased the 30º angle seat. flow is about 2-3cfm higher in high lift, but less in lower lifts.

B16A2

this is the result of this week work. repaired the b16a2 head i received days ago.

gained about 16-17CFM. flows 288CFM,  a little bit more than a K20A2 head.

the goal is to obtain 200hp, so with these numbers there is no problem in the flow side.

tomorrow i'll start working on the exhaust side and then change the valve guides to bronze ones.

state of the art B16A2

received this head 2 days ago.  it is previously worked by ''someone''.

his work speaks by itself. flowed worst than an oem spec head.

B16 intake dome

after holidays i got sick an entire week, so today a had a long shower an a morning drive through the mountain i worked a little bit on this prototype and prepared the work for next week, a K24 head.
finished the dome allowing 314cc extra for the plenum.

B16 manifold. Work in progress

started working on this manifold. this manifold will be designed for a high reving engine, 9000rpm at least. the plenum will be increased by 314cc, runners 21mm shorter and wider runners, +2mm.
 OEM manifols usually are designed with smaller plenum, longer and narrower runners seeking for a good throttle response,good idle keeping the air moving forward as the intake valves open an shut.
 When an intake valve opens, there is a short lag before the cylinder starts to pull air through the runner into the combustion chamber. A longer runner helps maintain the inertia of the air column so it will fill the cylinder faster.
Shorter runners, on the other hand, usually flow better at higher engine rpm. Reducing the length of the runners may allow the engine to make more power at the top end, but the trade-off may be a loss of power and torque at lower speeds.
 we'll see if my math and theory works on this manifold. there is an inconvenient on my design, due to i am using oem manifold, , the oem runners are curved, so cutting and decreasing the length of the runners, don't match, so i have to reduce the diammeter of the runner in the point i am going to wel both pieces.