KZScott
Needs a life
high on speed
Posts: 7235
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posted February 19, 2008 07:51 PM
Jim, at what point do you consider it a good idea to gas port pistons? what kind of mods does it take to reach the "well i guess i should gas port the pistons stage"
thx
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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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Y2KZX12R
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CompetitionCNC.com
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posted February 20, 2008 12:03 PM
Its a time issue. Ring reaction time.
The factory rings are thin and have faster reaction time compared to most of the aftermarket rings you see. Most of the common piston makers use thicker rings than the factory did.
Except CP, Mahle, and Cosworth from what I've seen.
So as a result at or above 8000 rpm the rings start to react to the cylinder pressure too slow. The pressure cant get behind the ring fast enough to push the ring out and seal the cylinder.
So its a combination of what ring package you are using and what RPM the engine will see.
Using a Napier 2nd ring will help to better scrape the oil which also is a cause of excessive blow by.
If you use a roto flow meter on the crankcase (oil filler hole) you can see and map blowby. You will notice that at a certain RPM (every engine is different) the blow by will suddenly tripple or go 5 fold in volume.
Thats how you can detect the effectiveness of your ring package and oil control in the engine.
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Y2KZX12R
CompetitionCNC.com
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entropy
Moderator
Posts: 8671
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posted February 20, 2008 01:04 PM
JIm.
are you talking abouta rapid increasing of crankcase pressure when the rings start letting more blowby across them? Couldn't just put a sensitive pressure gauge on the crankcase? Is that a roto flowmeter??
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dougmeyer
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moderated
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posted February 20, 2008 01:25 PM
Excellent points, Jim. I've always used a simple vertical float flowmeter and had similar results.
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It's not that I think you're dumb, it's just that so much of what you know isn't true....
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Y2KZX12R
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CompetitionCNC.com
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posted February 20, 2008 03:02 PM
 Edited By: Y2KZX12R on 20 Feb 2008 15:24
quote:
JIm.
are you talking abouta rapid increasing of crankcase pressure when the rings start letting more blowby across them? Couldn't just put a sensitive pressure gauge on the crankcase? Is that a roto flowmeter??
Yep, exactly Karl.
Its volume you are trying to measure not pressure. A pressure guage would just have a spastic needle and it would be a blur.
Doug, thats the baby. I just called it by a trade name that I am famililar with, "rotameter" from GF.
George Fischer makes them.
When I was doing design engineering on micro electronics and bio pharm water systems for US Filter and Tenergy we used them all the time for monitoring chemical intro into the filtration units and also for air blow down on the mixed resin bed units..... anyway, here is what one looks like.
http://www.pep-plastic.com/2005_pricing/george_fisher/GF_Rotameters.pdf
Sit down if you think you want to buy one.... there calibrated and VERY expensive. Luckly I didnt have to buy one. 
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Y2KZX12R
CompetitionCNC.com
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almost_les
Zone Head
Posts: 590
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posted February 20, 2008 04:50 PM
Edited By: almost_les on 20 Feb 2008 16:53
i'm planning on doing this to my 1199cc:
cams/springs
revving to 12600 ish
(maybe a bot-o-nos)
i've already got a pro pipe so lows don't matter to me just highs
a good stage one for something like this would be awesome!!!
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entropy
Moderator
Posts: 8671
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posted February 20, 2008 11:34 PM
Jim,
have you done measurements on yr 1375 with the JE pistons/rings used in the Muzzy kit?
If so did you identify the rpm where " the blow by will suddenly tripple or go 5 fold in volume"???
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Y2KZX12R
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posted February 21, 2008 04:55 AM
Edited By: Y2KZX12R on 21 Feb 2008 04:58
quote:
Jim,
have you done measurements on yr 1375 with the JE pistons/rings used in the Muzzy kit?
If so did you identify the rpm where " the blow by will suddenly tripple or go 5 fold in volume"???
Yes sir. At about 9000 rpms the rings started to flutter and blow by started to rise.
Expecting this to happen, because its "normal" to see this on most engines at some point if you rev them high enough, I opened up the 2nd ring gap an extra .004" to reduce trapped pressure. This usually works by raising the rpm point at which the flutter starts.
I'm looking into using .9mm/.8mm/1.25mm ring package. The problem is they dont make one in this bore and backspace.
So a custom ring package would cost about $25,000. They would have to make a special run and theres a minumum volume.
I looked into this in December and met with the Seal Power rep at PRI. We discussed this at length.
The draw back is that while offering excelent performance, a ring package like this would only last one season. You would need to replace the rings every year and the performance degrades over time. Quite quickly compared to larger more "durable" ring packages.
Another approach is to control windage better. Block off the oil squirters to the cylinder walls and make strippers and baffeling. Run tighter bearing clearances.
but this also has its longevity drawbacks.
Yoiu dont get somthing for nothing.
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Y2KZX12R
CompetitionCNC.com
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Y2KZX12R
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CompetitionCNC.com
Posts: 3762
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posted April 08, 2008 05:25 PM
The stage 1 and 2 zx12r head development is done!!! We started to cut them a few weeks ago. The feed back so far is excellent.
I'll try and get some info on here for you guys soon.
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Y2KZX12R
CompetitionCNC.com
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MadMike
Moderator
FEAR THE BLACK FLAG!!!!!!!!
Posts: 6579
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posted April 08, 2008 07:25 PM
is there a different design for Spraying? like my setup... 1270 with a 60hp shot?
I am going to send you my "spaz" race head so you can compaire here soon...
I will call you first and work it out!
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200-MPH CLUB MEMBER!
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