2000redrocket
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posted January 30, 2010 01:20 PM
shane. on the valve adjustment i get a piece of paper and draw the head and valce circles and the cam chain side to keep the oriention .i make the valve circles big enough to write in easy and then write each valves clearence in the respective circle. then on the ones i have to change i write the shim size under the clearence. then i know the target shim i am looking for and i know all the shim sizes and clearences. i usually can move around some shims and only need to buy half of the number of valves that need changed. do not laugh but gene and i have 16 45acp shells in two rows of eight that we deposit each valves shim into with the cam chain side marked.we use a magnet anyway so they are easy to gain access to.
as far as starting with no shims it sounds expencive. dan from the old action machine (who still owes me 400 bucks with intrest) made a rig for a surface grinder and would knock the larger ones down to what he needed.
we had the valves set way loose like around 12 to 14 thou. and after i went 1000mi i shimed them down to .006 all around. i picked up over .1 in the 1/4 easy. but i had to keep a close eye on the clearence being that tight.
each .05 is .002 larger or smaller. it is easy to figure out. 2.50mm is .002" larger than 2.45mm.
have fun and hope you get your papers so you can come to cecil one night.
  
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KZScott
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posted January 30, 2010 07:10 PM
quote:
quote:
quote:
See how big the bump is? It's like the port doesn't even line up. Look at the port to the left in comparison.
Quoting Jim, about his new port design:
"With the over sized bronze seats we are able to addresses the short turn issues where there wasnt any material to work with on the outer most ports of cylinder's 1 and 4."
I wonder if this is the issue he was talking about?
I dont think you are pointing at the short turn area. i think thats the other side. looks like lots of material can and should be removed where you are pointing
i could be wrong....?
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00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
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Shane661
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posted January 31, 2010 04:53 AM
Yeah, Scott, I guess you're right. I was thinking that the port not lining up like that might require some changes on both sides?
I don't really know. I need to do some more reading about port nomenclature. This is all new to me.
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Y2KZX12R
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posted January 31, 2010 06:30 AM
With a fresh cup of coffee this morning, I'll give you my spin on some of this stuff in general.
There are different methods of casting aluminum. The "lost foam" the "permanent mould" "die casting" and several types of "sand casting".
Engine blocks and heads etc. are usually sand cast. They assemble the port and water jacket cores that are made from moulds and pour in the aluminum.
When they assemble these cores they have to be positioned exactly where you want the water jacket and ports to be located. On most heads there is some sort of core shifting when they assemble the "box". The amount of "core shift" depends on the accuracy of the tooling and moulds and the person or machine setting it up for the pour.
Many times you can see consistent core shift in every head. This is usually an error in the setup in the "box".
Core shift in the iron heads in the 1960's 70's etc was terrible so the engineers had to account for it and build in extra safety margins so the castings wouldn't be thin to the water jacket in critical areas. Even with these considerations core shift is still a nightmare for head porters. in the mid 90's GM started to use new processes for casting the LS series of engine parts. The core location control was improved big time. You could see core shift as much as .060" or more on some older heads but now .020 was more common.
As far as bike heads go..... the castings in the 80's and early 90's had quite a bit of core shift. zx11 intake ports can have .060" of core shift. But they too have reduced this now and its less of a problem. Zx12 heads are much better than zx11 heads were. When they went to the bucket design they had to be.
The benefits of controlling core shift are the ability to make thinner castings and better water jackets to control the heat flow. Also the ports are more consistent from a performance standpoint.
its not always easy to see core shift in a casting unless you know what to look for. The machining is one place you will pickup on core shift. These heads are all machined on state of the art CNC machines so the indexing and machining is exactly correct. When you see what looks like the machining is off in the valve bowl its really the casting core shift that's off.
In the valve bowls you will see where the cutter comes down to cut the valve guide bore and valve seat pocket. This is done in one operation with one custom tool. you will see that the tool goes down into the valve bowl and sometimes cuts more material on the long side of the port. sometimes its on one side of the port. Core shift can be and often is 3 dimensional.
As for performance.... some core shift is really bad for performance and some has little to no effect. It all depends on where and what it is. Typically issues on the short side impact performance much more than on the long side.
Part two after breakfast.....
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Y2KZX12R
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posted January 31, 2010 06:55 AM
The parting lines you see on the port sidewalls etc. don't have any real impact on flow or performance. But using a flapper wheel or flapper stick on ports to "polish" the ports does have an impact.
when air moves over a surface the air close to the surface doesn't actually move. This layer of non moving air is called a boundary layer. The thickness of the bounder layer depends on a few things like the speed of the air and the surface texture.
as the velocity of the air increases the bounder layer gets thinner. The boundary layer on a very smooth surface is thinner than on a rough surface as well.
So by polishing the ports you are effectively making the port "bigger" even if you aren't really removing much material. The fact that you thinned the boundary layer allows more moving air threw the port. Typically you see a 2%-5% increase in flow just from this, depending on the port size and design.
Sharp edges in a port are always very bad for smooth air flow. The biggest gains are in smoothing any sharp edges.
The sharp edges around the valve guide are not a problem. There not sticking up in the air flow. The same goes for the air inlet holes in the exhaust port valve bowl where fresh air enters the port. The holes are so small, so if the hole is blocked off at the other end then there is no flow threw these holes and the air just passes right over them.
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Shane661
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posted January 31, 2010 07:04 AM
 Edited By: Shane661 on 31 Jan 2010 15:04
Jim, thanks for your input.
Regarding port polishing; is this the sort of thing that everyone does differently? You know, like port finishes are part of the "secret" stuff that changes from vendor to vendor?
Do intake and exhaust ports get different finishes?
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KZScott
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posted January 31, 2010 07:40 AM
thank you Jim!
____________
01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
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2000redrocket
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posted January 31, 2010 08:05 AM
good morning guys. shane the finnish question is a good one to ask jim. i see exhaust highly polished and intakes just made nice but some what rougher i guess to help keep the fuel intrained in the air and then some of the roundy round guys have a spiral thread going all the way into the intake valve i guess for swirl.
jim does the thread grouve get used up your way?
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Shane661
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posted January 31, 2010 10:09 AM
Edited By: Shane661 on 31 Jan 2010 22:06
Porting Wiki (very good read/links!):
http://www.search.com/reference/Cylinder_head_porting
Popular Hot Rodding Porting Basics Article:
http://www.popularhotrodding.com/tech/0610phr_cylinder_head_porting/index.html
Another small article, covers a few discussion points of this thread:
http://www.chevyhiperformance.com/techarticles/95518_small_block_cylinder_head_porting/index.html
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Y2KZX12R
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posted January 31, 2010 06:29 PM
Shane, I use a .020" step over and a .375" ball or lollipop tool. Exhaust ports get a .020" step-over and usually a 1/4" ball. This gives a scallop height of about .0002" And a very smooth finish.
Most of the CNC ported heads I see have a much larger step-over. I also do a spiral cut and not a 1 way cut like most other shops. Also I always do a climb cut.
Its really no secret, and other shop can see how I cut my ports. But reducing the step-over requires more time to do the operation and time is money. So most shops wont want to take the extra time.
On some automotive "street" heads with poor velocity we do texturing. Typically these are heads on carbureted engines that need to start with a choke on and fuel dropout on cold start can be a problem.
Port fuel injected engines are far less prone to cold fuel dropout on start-up.
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Shane661
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posted February 01, 2010 04:40 PM
Edited By: Shane661 on 2 Feb 2010 00:44
quote:
Shane, I use a .020" step over and a .375" ball or lollipop tool. Exhaust ports get a .020" step-over and usually a 1/4" ball. This gives a scallop height of about .0002" And a very smooth finish.
Most of the CNC ported heads I see have a much larger step-over. I also do a spiral cut and not a 1 way cut like most other shops. Also I always do a climb cut.
Its really no secret, and other shop can see how I cut my ports. But reducing the step-over requires more time to do the operation and time is money. So most shops wont want to take the extra time.
On some automotive "street" heads with poor velocity we do texturing. Typically these are heads on carbureted engines that need to start with a choke on and fuel dropout on cold start can be a problem.
Port fuel injected engines are far less prone to cold fuel dropout on start-up.
Although I don't understand all of the terms/tools, it gives me something to further research. Thanks! 
What about the finish of the combustion chamber?
Do you want any texture in there?
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KZScott
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posted February 01, 2010 06:17 PM
as far as i know smooth/polished to reflect heat, especially in a nitrous or forced induction application. sometimes even ceramic coated.
this pic is from Doug Meyer, (hopefully he doesnt mind ) I copied the pic from a classified add he posted way back.... I think its in his turbo 12
____________
01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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Y2KZX12R
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posted February 03, 2010 07:10 AM
Yes, you want the chambers smooth. The bike heads have nice chambers. Not much to be done there. On some heads we cnc the eyebrow areound the intake valves for better flow.
Much like what you see in the above picture.
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Shane661
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posted February 03, 2010 09:35 AM
Edited By: Shane661 on 3 Feb 2010 17:40
Intake seat & valve:
Regarding valves, do aftermarket valves flow any better than the oem? Or are the designs basically the same, with the difference being materials?
The main options I see outside of oem are stainless steel (various manufacturers), and the Kibblewhite products. Any advantages to either product?
Shane
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Shane661
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posted February 03, 2010 11:58 AM
Edited By: Shane661 on 3 Feb 2010 20:11
Cutaway shots of the outside ports, from an old Bikeland article:
I don't really have anything to compare these photos to, but I found them interesting. I think I can see the problematic "short turn" area. I would like to see cutaway views of some other heads, if any of you have some pics? I think these type of pics are pretty common in promotional materials...
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Y2KZX12R
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posted February 03, 2010 02:51 PM
Yep, that's the problem area. Good eye Shane, it IS actually concave in that area. You cant really see it in these pics but...
The zx12 and busa heads as well as all the gsxr1000 and zx10 heads are all much better in the short turn area. Thus they all have a better flow coefficient.
On our stage 2 zx14 head we were able to correct that with the 1mm O/S valve and a new larger bronze seat. The flow coefficient is as good as a stage 2 busa and almost as good as the zx12r head.
Bryan at Quantam Motorsports regularly gets over 200 hp on Brocks dyno with our stage 1 head and cams and thats on a stock bore and stock stroke engine with factory pistons!!!
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Shane661
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posted February 09, 2010 09:39 AM
Edited By: Shane661 on 9 Feb 2010 17:40
Can someone shine some light on what is going here in the intakes?:
The bumps seem pretty big! Is that going to affect high rpm power?
What about the sharp edges here and at the port divider? It just seems very restrictive.
Shane
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Y2KZX12R
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posted February 09, 2010 10:35 AM
The bottom is where the fuel cone is sprayed into the port. The top it just the beginning of the divider.
Nothing to worry about.
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Shane661
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posted February 09, 2010 12:42 PM
Edited By: Shane661 on 9 Feb 2010 20:45
Looking at the combustion chamber, I notice two very sharp, raised edges:
Are these edges raised and sharp for a good reason??
Shane
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Shane661
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posted February 09, 2010 03:57 PM
Edited By: Shane661 on 9 Feb 2010 23:58
Also, earlier Jim wrote:
quote:
Shane, I use a .020" step over and a .375" ball or lollipop tool. Exhaust ports get a .020" step-over and usually a 1/4" ball. This gives a scallop height of about .0002" And a very smooth finish.
Can someone translate? 
Maybe someone here uses similar tools and/or has a link or pictures?
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KZScott
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posted February 09, 2010 05:22 PM
picture a grinding ball, like for a dremmel (.375). it makes a pass over the material and leaves a groove, perfect radius(its a ball), then it makes another pass only this time a little bit farther in (.020). another perfect radius. between them is a little peak, kinda like a ripple in water. the height of that ripple is .0002. about a BCH 
____________
01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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KZScott
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posted February 09, 2010 05:27 PM
quote:
Looking at the combustion chamber, I notice two very sharp, raised edges:
Are these edges raised and sharp for a good reason??
Shane
quench pads i think is the correct term for that area(from the edge to the outside of the bore). i put a very slight radius on the very edge the same as i did to the sharp edges of my pistons
____________
01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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Shane661
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posted February 09, 2010 05:32 PM
Edited By: Shane661 on 10 Feb 2010 01:33
quote:
picture a grinding ball, like for a dremmel (.375). it makes a pass over the material and leaves a groove, perfect radius(its a ball), then it makes another pass only this time a little bit farther in (.020). another perfect radius. between them is a little peak, kinda like a ripple in water. the height of that ripple is .0002. about a BCH
Oh ok, so this is something you can can't really do by hand. It sounds like something a machine must do? The rest of us just use a dremel and a sanding drum?
Thanks for the explanation, Scott.
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KZScott
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posted February 09, 2010 05:42 PM
the surface finish probably has an equivalant to a certain grit of sand paper, but the shape is something nobody would have the precision to exactly replicate. guys like Jim that do a very tiny step over have a much smoother finish as the "ripples" are smaller.
____________
01 ZX-12R 8.84 @ 156.3 no bars, DOT tires. Pump Gas, NA.... turbo 8.47 @ 164.
00 ZX-12R 8.62 @ 165.2 no bars, slicks, Pump Gas, 55 shot.... turbo 8.32 @173
00 ZX-12R Fastest NA Kawasaki in the world 1: 222.046 1.5: 226.390 Loring AFB
00 ZX-12R street turbo 1: 227.9 1.5: 234.1 Loring AFB
00 ZX-12R LSR turbo 1: 263.1 1.5: 266.5 Loring AFB Worlds fastest ZX-12R
CMG Racing RCC Turbos
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Shane661
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posted February 09, 2010 05:52 PM
Edited By: Shane661 on 10 Feb 2010 01:57
You did yours with drums of varying grits, correct:
http://www.bikeland.org/board/viewthread.php?FID=13&TID=34886&pagenumber=6
quote:
start out with the heavy grit on the casting flash, then do most of it with the finer stuff
i had some 120 grit drums i used too...
Or did you also use a ball in some spots?
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