Hi, I understand that tubed headers are better for NA motors, as they assist on the flow that is created by the motor with their scavenging effect. With a blower motor is there really any advantage? If the manifolds have large passages and huge extensions reducing restrictions, would tubed headers really have any advantage since scavaging would have little effect on the pressurized flow? Has anybody dyno'd say stainless marine, dynaflo, or imco powerflow plus against cmi, lightning, etc?
Thx
Larry

I've never personally dynoed myself but have been told nothing beats Stainless Marine on the dyno even N/A motors. Chief Engines has done back to back comparisons... On drag race stuff they run zoomies on blower motors to take some of the torque out of them.

never heard of that theory,why would any racer want to throw away torque?

They all throw it away cause the motor makes to much torque if they don't get rid of some of it they'll fry the tires and never make it down the track...

now adays they manage that in the clutch

back to the op,s question,headers are nice but they are expensive and dont last forever,imo the manifolds you mentioned are all good for your n/a engines,some say the stainless marine gen3,s flow as good or better than headers and they dont crack.the imco,s also flow very good.

The point is was trying to make is tubed headers draw the exhaust out, which aides in overall flow and the ability to make more power. But blower motors are already jamming the air threw, just wonder if the scavaging effect that aides on N/A motors have no effect on blower motors, or at least less effect.

A tube header on a blower motor will still make more power. Problem is with the marine stuff the headers are very poorly designed... I would give Chief a call they have done dyno comparisons on with marine exhaust from what I'm told the Stainless marine gen iii come out on top.

When you say poorly designed, I assume you mean for performance. My thoughts are SM Gen III will probably perform as well as most headers on the 5 to 6k range (etop, lightning). When you get to the 7k and above, very long tube headers, you will see better performance, but how much better? If I can achieve 1000hp with blower motor and gen iii, what would I see with the high end headers? 1050? I would love to use diamond marines thunder headers because I believe they are the best of both, but they don't work with the centrifical SC.

the ole keith eckert tubular sty;r vast manifold also came out on top and out flowed a ss header....when stwlling was still mking headers the salesman told me that they were making manifold that out performed their headers but fr some reason they quit making them..