Kz 1000 Head porting

...

Here's a "genuine" Pro Stock Suzuki head. This was ported by Darin Morgan for Matt Smith's Suzuki. This started life as a Vortec head and was heavily modified from there.

In this photo, it's not completely finished.

This a good example of "bowl volume". You have to remember this motor will spin in excess of 13000 RPM and uses special valve buckets to achieve an effective cam lift of .835". The buckets are good for one event.

Valves are 46/39

ACFM @28"
Lift No. 1 No. 2

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0.2000 116.9 108.6
0.3000 195.1 153.4
0.4000 259.5 186.7
0.5000 295.0 205.6
0.6000 312.7 212.3
0.7000 321.4 212.9
0.8000 322.0 214.4
0.9000 321.1 216.5
1.0000

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Average: 268.0 188.8 @28"

Peak @10" converts to 192CFM [intake]
Stock Vortec is 160CFM @10" [intake]

Don't fall into that old trap of matching the exhaust port to the gasket. Leave some aluminum there for anti-reversion.

Valve Buckets

larrycavan wrote:

Here's a "genuine" Pro Stock Suzuki head. This was ported by Darin Morgan for Matt Smith's Suzuki. This started life as a Vortec head and was heavily modified from there.

In this photo, it's not completely finished.

This a good example of "bowl volume". You have to remember this motor will spin in excess of 13000 RPM and uses special valve buckets to achieve an effective cam lift of .835". The buckets are good for one event.

Valves are 46/39

ACFM @28"
Lift No. 1 No. 2

---

---

---

0.2000 116.9 108.6
0.3000 195.1 153.4
0.4000 259.5 186.7
0.5000 295.0 205.6
0.6000 312.7 212.3
0.7000 321.4 212.9
0.8000 322.0 214.4
0.9000 321.1 216.5
1.0000

---

---

---

Average: 268.0 188.8 @28"

Peak @10" converts to 192CFM [intake]
Stock Vortec is 160CFM @10" [intake]

Don't fall into that old trap of matching the exhaust port to the gasket. Leave some aluminum there for anti-reversion.

definately leave port smaller than the gasket in my experiance anyway with no flow bench on turbo style heads the exhuast side is where the kaw 2v heads tend to benefit most since intake is force fed anyway running a size over on exhuast valve with the d shaped port and stock size intake valve with the port and bowl just cleaned up a little seems to bring these things to life

Started to open up the exhaust ports a bit... well ... . actually quite a bit. Ended up with quite a pile of shavings after a while.. and I have just got started. I havn't started in the pocket area yet .. or around the guides... mostly just the exit of the port. here are a few pics.

On N/A motors, there's a tendency to go overboard on the exhaust ports. The floor of the port is dead area. You can find this yourself with some simple tools.

A simple water column probe can be made out of a section of brake line and some hose. Google U TUBE Manometer.

A shop vac with hose connected to exhaust side.

A piece of 3" ID tubing for a cylinder.

Use the probe to find the dead zone in the floor of the port.

I am guessing from my search results that the manometer you speak of is just a vaccuum sync guage. If so I have a nice digital one that I use at work. is it possible to use this to test port flow. I have thought about it before but didn't know if it was possible or accurate it could be. How does the shop vac vaccuum campare to the engine vaccumm read my a guage? would a plenum need to be made to equallize pressure between the four ports?

you are applying a constant vaccumm to the port and using the brakeline with the guage and hose attatched to search around the port area for high and low areas. Do you need to use a type of mercury stick/guage that has an air bleed screw in the line? I got some of those also.

since i cant get none of my bike pictures to load heres a bigblock chevy exhuast port to give you an idea about the short and long side,although larry has forgotten more about this stuff than ill ever possibly know!

What is the best texture for the ports .. both intake and exhaust. It looks like both are acceptable. I was taught that a rougher intake helps aid in fuel atomization and a smooth exhaust aid in excaping gas and reduces carbon deposits. Also .. what is the point in polishings the combustion chamber. Wouldn't this prevent the cylinder head from disapating heat and make the engine run hotter/... I know that painting the motor flat black aids the most in heat dissapation.

i have my ports and chambers thermal coated to keep the heat in chambers and exhuast port but keep intakes cooler,also do pistons and valve faces

larry, quick comment.

when you open up the valve seat to the X% of the valve diameter, would it be a true statement to say that your runner should NOT exceed this overall dimension?

or, will this not matter if it's blended smoothly with the larger diameter?

just wondering if this would raise the velocity some to help with TQ at lower lifts?

this will dictate the face angles on the valves, too, correct?

--r

gearhead119 wrote:

What is the best texture for the ports .. both intake and exhaust. It looks like both are acceptable. I was taught that a rougher intake helps aid in fuel atomization and a smooth exhaust aid in excaping gas and reduces carbon deposits. Also .. what is the point in polishings the combustion chamber. Wouldn't this prevent the cylinder head from disapating heat and make the engine run hotter/... I know that painting the motor flat black aids the most in heat dissapation.

On the intake runners, 60G flapper paper on a flap stick works well. I woulnd't go finer than that. While 60G sounds rough, in reality, it's not. Quite surprising how fine a finish they actually leave.

Exhaust ports can be smoother.

You want to see where the fuel goes? On the flowbench, I crank up as high a pressure as I can pull across the valve with it at cam max lift. Then spray brake cleaner into the runner. It shoots straight down the port and slams into the long side of the bowl, above the valve seat before it exits.

There's a reason valve seats are roughed up in a lot of full out race motors..