designing and building manifolds.

[marshall]

I am very interested in how you made those velocity stacks.

It's been proven recently on the flow bench and on the dyno that velocity stacks can do more harm then good on turbo cars. They work great under vacuum conditions, but cause turbulence under boost...just thought I'd throw that in so you can research it yourself and maybe save yourself some time when making your manifold.

Marshall

 

[tanner261]

It's been proven recently on the flow bench and on the dyno that velocity stacks can do more harm then good on turbo cars. They work great under vacuum conditions, but cause turbulence under boost...just thought I'd throw that in so you can research it yourself and maybe save yourself some time when making your manifold.

Marshall

Could you provide a link to the data supporting this claim?

 

[marshall]

nope...probably try searching turbomustangs or supraforums...

 

[RED_AWD_BLUR]

I am pretty sure it is turbulent anyway, because it is not laminar flow. Reynolds equation is given by Re=(density*Velocity*pipe_diameter)/Dynamic_Viscosity lets assume a volume flow rate of 505Cfm ~ 0.238m^3/s,
pipe_diameter= 2.5in~ 0.6125m
pipe crosssectional Area= 0.25*Pi*(0.6125m)^2= .002946m^2
Velocity=(0.238m^3/s)/(002946m^2)=80.89m/s
Air at standard Atm conditions, close enough for example even though press. is at 1ATM

from tables:
Dynamic_Viscosity=1.79*10^-5 (N*s)/m^2
density=1.23 kg/m^3

Re=(density*Velocity*pipe_diameter)/Dynamic_Viscosity

Re=340440

that is a pretty freakin far into turbulent flow already.... anything higer than Re=4000 is considered turbulent flow...

so I don't think the ecuse about it being more turbulent is going to affect it much.

any way I have got to class

 

[RED_AWD_BLUR]

that 2.5 " diameter would be the aproximate di for the UICP. the runners would be even smaller which impacts it by the square. any way I dond think simple turbulence is what takes down horse power. besides last time I knew I thought turbulence helped atomize/mix the fuel better.