Offshoreonly.com - What's wrong with AFR's exhaust port?

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Quote:

Originally Posted by KAAMA (Post 4272676)

What did Darrin Morgan charge for something like that, Bill? I am wondering how many CFM numbers it takes to gain or make 1-hp??? Does anyone know?

Like I have said previously, if it is for a car race application where saving a pound of weight here and there as well as low as 1-hp, then maybe I can understand these small increases for the time and expense involve for a drag car clocking time in the 1/4 mile....or a circle track car, but I think a boat is a whole different animal and these CNC ports have already filled the gap considerably.

I will admit that I like the ports to be as efficient as possible, and I am sure every little bit helps, and I suppose it depends on how much $$$ a person wants to spend, but where do I draw the line for a pair of hi-zoot offshore engines with supercharging that are already equipped with CNC ported heads that are going in a pleasure boat? Are we splitting hairs here?

$1200,got us right at 1000hp on motor.before we were at 973hp on motor.but we could hit it w/ more nitrous and not speckle the plugs.

Quote:

Originally Posted by sutphen 30 (Post 4272972)

at some point asingle man ported a set of heads,,they worked,,they got cnc'd splashed..

Years ago yes they were "splashed". Today it's a different story. When getting into a more custom CNC'd head they use computational fluid dynamics to design the port. The port is designed to meat the engines air requirements based on cubic inch and rpm. Based off of the port model they program the CNC to produce the port.

While no engine builder, l have to believe every combo possible under the sun is going to have a sweet spot, and the heads are cast and ground somewhere in the middle, and if you have the funds and need for the last hp on the table, its there for the taking. Afr or any other after market supplier has no idea what a particular piece will be used on, so it's somewhat generic off the shelf, although far beyond stock.

Quote:

Originally Posted by buck35 (Post 4272993)

that,s not really true,afr makes a lot of different heads for a lot of different applications.if you contact them with what you have they will tell you witch head would be best for your application.i will give you an example,a oso member asked afr what head would be the best to use on a 454 with a small blower,their was a chitstorm about that very same setup on a thread and that is why he asked,he finally got his answer today.they said the 305 would be the best head for that application.

I don't know zip about blower motors or forced induction. Is The efficiency of a right sized head important in a forced induction application?

Quote:

Originally Posted by buck35 (Post 4272908)

Both a blessing and a bane, the skilled craftsman teaches a programmer instead of the next generation

The programmer is the next generation.

This whole topic of head porting conversation has revolved around subtractive machining, traditional cutting. I can't wait to see a head designed and executed from a blank sheet with an additive manufacturing approach, 3D printing.

Quote:

Originally Posted by BenPerfected (Post 4273132)

I don't know zip about blower motors or forced induction. Is The efficiency of a right sized head important in a forced induction application?

Absolutely. The only difference between the N/A and Blown motor is one has compressed air flowing into the cylinder one has atmospheric air. In essence with a blower you are creating a different atmosphere.

Quote:

Originally Posted by Cole2534 (Post 4273134)

Could you elaborate on your idea a little?

Better cooling passages were my first thought.