(I have trouble in finding the stroke length and fuel flow rate)

From Heywood,E2.11

You are designing a 4 stroke CI to provide a brake power of 300kW,Naturally aspirated at its max rated speed.Based on typical values for brake mean eff.pressure(bmep){700kPa to 900kPa} and max mean piston speed,estimate the required engine displacement,and the bore and stroke for sensible cylinder geometry and number of engine cylinders. What is the maximum rated engine speed(rpm) for your design? What would be the brake torque and the fuel flow rate(g/h) at this max speed?Assume a max mean piston speed 12 m/s is typical of good engine designs.

I use the usual equations which relate bmep to max power(i.e max rpm) and bmep to max torque(i.e max bmep)

bmep=Pb(max)∗nR∗10^3/Vd∗N(max) ; nR=2 for 4 strokes

bmep(max)=6.28∗nR∗T(max)/Vd

where, Vd is the displacement volume=number of cylinders*3.14/4*B^2*L

where B-bore,L-stroke

**The problem I have is that once I have found the bore dimension,I have no other way of finding the stroke length i.e I just have to assume the stroke=bore and continue the problem. Also,to solve for fuel flow rate,I have to assume that the sfc for NA diesels is usually 200(g/kWh) which the question doesn't say I can assume.Any another ways?What answers do you get?I get a bore dia of 388mm.**

Correction to my calculations:

I added an unnecessary *10^3 in the formula for bmep. Stupid of me. In that case,the bore dia comes to 115.5mm. The calc. of stroke stays the same.

Note to moderator:I already posted the same on physicsforums but am re-posting here since there were no replies.