Chris Sunkin

With all the recent and highly enlightening cylinder head discussions going on, I'm curious as to how supercharging affects things.

Does supercharging simplify or complicate head selection or does forced induction overcome most issues? One would assume that a large engine would need a larger intake volume/flow but does supercharging overcome the issues of using a larger flow head on a smaller displacement engine? Are things like CNC'ing, hand porting port volume matching less critical- or wholly unnecessary?

excalibur32

It still has some bearing just not quite as critical, still you don't want junk.

RunninHotRacing163.1

Not as critical as the N/A motors but even Teague suggests his Competition CNC valve job for supercharged applications to help get that air out of those cylinders pronto

heavyhauler

Obviously superchargers, when matched up with all the right parts (heads, camshafts, rotating assemblies, injectors or carburetors, etc.) make some big numbers, typically more than a N/A motor with similar matched for use setup. What I wonder is how much horsepower is used/wasted to turn a supercharger and does it become a negligible gain on a gasoline engine. I know if you use alcohol or nitro for fuel, then the blower helps to make gains unachievable with natural aspiration. A blower definitely offers a lot of hype that an antiquated intake and carburetor don't.

DMOORE

Well, I know more than a few people who put huffers on 500HP's, and now are running well over 750hp with them. There is a reason blowers are so popular.


Darrell.

RunninHotRacing163.1

[QUOTE=DMOORE;2421193]Well, I know more than a few people who put huffers on 500HP's, and now are running well over 750hp with them. There is a reason blowers are so popular.

fastlane40

I don't think my 540 would have made 900hp without the blower and still run on 92 octane.

mrhorsepower1

Cylinder head selection is still very important, per application. Intake and exhaust runner volumes and camshaft design are still critical in optimizing a supercharged engines performance. I have dyno other engines built by different shops that made no where near the power they should have because the cylinder heads were to large or the camshaft was completely wrong. Just as with a N/A engine having the right combination will make the difference between gains or very little gains.

Smitty

iTrader: (1)

In my experience you still need to have a specific to the application cam. The cylinder heads must flow extremely well on the exhaust side. Intake flow is not as critical. Overall if your heads are matched and flowed well then adding a blower makes it all that much more sweeter. Again, I must stress the cam is a huge part that must be optimized knowing a blower will be used.

heavyhauler

As I said, with the right parts you can get big numbers with blowers, and I'm not against them nor for them. Also, I have limited experience with boat motors and how the torque application and horsepower that is made with big blocks makes them so popular in boating. I came from the oval track world where we make 600 to 650 horsepower on 358 cubic inches with 9 to 1 compression and a single 750 holley carburetor on premium pump gas that you can run indefinitely if you take care of the valve train properly, which is not a lot different from what I read in a lot of posts here, so I'm not real impressed with 750 horsepower on 500 or more inches with a blower, therefore I ask the question, how much power is required to turn the blower. I would also think that any n/a motor of 500 cubic inches should easily attain 750 horsepower in todays world if assembled with the right pieces, particularly heads, camshaft and exhaust, and last equally as well as anything else making that kind of power if properly maintained. I think you ultimatley have to decide what you want to do, and if it's not all out competition, then you have to somehow get in the middle of the road.