KZScott
Needs a life
high on speed
Posts: 7235
|
posted June 27, 2010 09:25 AM
stock vs JE
I was curious about how thick the 1287 pistons were compared to stock, and i just so happened to have a few paper weights kicking around
(btw the JE would be thicker out of the box but the point has been sanded lightly to round it, it was also much tougher to cut)
My CR is too high on my current build, so Im going to remove a little material from the pistons and add an oem base gasket. I dont really want to touch the center where just about every piston seems to melt when abused, so im going to remove some of the dome on the sides besides oil holes its solid down to the pin.
____________
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
  
|
Shane661
Needs a life
Posts: 11494
|
posted June 27, 2010 10:52 AM
 Edited By: Shane661 on 27 Jun 2010 20:00
I think I started a trend with the piston cutting.  Great pics!
Why is the bottom ring land so tall on the JE's?
|
KZScott
Needs a life
high on speed
Posts: 7235
|
posted June 27, 2010 12:11 PM
its a great way to get an inside look
no idea on the reason for bigger rings
heres what i came up with, took a gram off of the pistons (weight is of piston and wrist pin), going to recheck CR after supper to see if I need to shave more or not
____________
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
|
entropy
Moderator
Posts: 8671
|
posted June 27, 2010 03:28 PM
your CR was too high for what????
____________
This moderator uses moderation in moderation
|
Johnnycheese
Pro
Posts: 1008
|
posted June 27, 2010 03:54 PM
you can never be too high
____________
Builder and tuner of some of the fastest N.A. and P/A Hayabusas and ZX12 /14 in Texas
|
Phantom13
Zone Head
Posts: 736
|
posted June 27, 2010 04:06 PM
Johnny, are we still talking about compression? =)
____________
"The only place Success comes
before Work is inside the Dictionary."
|
KZScott
Needs a life
high on speed
Posts: 7235
|
posted June 27, 2010 04:33 PM
pump gas
____________
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
|
KZScott
Needs a life
high on speed
Posts: 7235
|
posted June 27, 2010 05:13 PM
Edited By: KZScott on 28 Jun 2010 01:35
CR is still in the upper 14s so i took more material away. down to 336 grams on the one im working on. time to call it a night
a little calculating with density tells me i removed about .75 ml of material, and adding a .010" base gasket "should" put me around 13.7:1
____________
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
|
JOHNJ
Novice Class
Posts: 70
|
posted June 28, 2010 04:46 AM
Why not just lower the deck height and keep the material on top of the piston for strength when N20 is used?
|
KZScott
Needs a life
high on speed
Posts: 7235
|
posted June 29, 2010 12:56 PM
Im not removing material from the thin area of the piston, its basically solid down to the pin minus an oil hole. the center where pistons usually melt is remaining intact.
I would have to have abot 60 thou on squish to get CR whre i want it without piston mods, and thats takes away from the effictiveness of the squish band/pad
a plus is the pistons are also getting lighter
____________
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
|
KZScott
Needs a life
high on speed
Posts: 7235
|
posted June 30, 2010 03:58 PM
success. 13.7:1 with the shaving and adding the oem .010" base gasket.
____________
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
|
dougmeyer
Needs a job
moderated
Posts: 2713
|
posted July 01, 2010 09:13 AM
Edited By: dougmeyer on 1 Jul 2010 17:15
A better way to have accomplished that would have been to machine a flat into the peak of the dome from end to
end. More precise, less material removed, and you would have helped maintain turbulent flow in the CC. Theoretically, you've actually increased the chance of detonation. You're choice not to increase squish was a good one.
____________
It's not that I think you're dumb, it's just that so much of what you know isn't true....
|
KZScott
Needs a life
high on speed
Posts: 7235
|
posted July 01, 2010 11:58 AM
Doug, if I remember correctly, thats what Muzzys did with their 1270 vs 1361 pistons(originally), but guys were warned not to spray the machined pistons heavily as the center was thinner.(this advice may not have been from Muzzys, but just average racers) that was my reason for not doing that. I never really thought about how I was affecting turbulence. could you go into more detail?
squish is now .041 -.042" with the .080" spacer and the oem .010" gasket
____________
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
|
KZScott
Needs a life
high on speed
Posts: 7235
|
posted July 03, 2010 07:36 AM
the easy way to get the top end together
____________
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
|
dougmeyer
Needs a job
moderated
Posts: 2713
|
posted July 05, 2010 02:48 PM
Scott,
I think that recommendation was for a much greater reduction in C/R. You could get down to where you are safely. Have you actually cc'd your set=up and measured the actual C/R?
____________
It's not that I think you're dumb, it's just that so much of what you know isn't true....
|
KZScott
Needs a life
high on speed
Posts: 7235
|
posted July 05, 2010 05:27 PM
yes, the 13.7:1 is actual, by greasing the cylinder, rotating piston to tdc, wipe away extra grease, install head, level it, fill combustion chamber to get compressed volume. compressed volume plus volume of cylinder (using the bore and stroke) over compressed volume = CR
____________
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
|
dougmeyer
Needs a job
moderated
Posts: 2713
|
posted July 06, 2010 06:29 PM
Nice.
____________
It's not that I think you're dumb, it's just that so much of what you know isn't true....
|
|
|
HOME
NEW TOPIC