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How to: SQUISHBAND your engine

H

hass

New Member
lincx said:
i am bit interested with this mod to try it into my vixion kit but i experienced knocking sound of the intake valve at my piston because im using raider valve and v150 high lift cams...because of my valves bigger diameter (22) and greater cam load the valves kisses the piston thus hearing knocking sound from the engine luckily no damage or scratch at the piston nor block was made... so we counter the problem by coupling the valve gasket using the stock gasket of the 135 placing it on top of the vixion valve gasket...if i push the idea thru how much mm shaving (which is safe) can the vixion piston can to accommodate the porting of the valves if i squishband the vixion block?
please post your know hows on this... TIA!
Click to expand...
I have mounted 2 blocks with vixion cylinder and big valave head .
But I have adjusted the piston to the valve .
I have maked the valve pocket .
To the first cylinder I have shaved off the piston from 1mm (to reduice the big pocket from the oem piston ) and after I have adjusted the cylinder to have one difference from 0.3mm beetween the top of the piston and the top of the cylinder .
Result = little more than 6bar compression .

To the second motors I have just take off the gasket under the cylinder and adjusted the piston to 0.01 to 0.03mm deeper than the cylinder :
Result 6.5bar compression .

With the big valve head you really need to do the pockets to piston .
 
H

haen

Super Veteran
with correct compression, 150 cc vixion tuned up block, special cam (deliver one as sample to u hass), big valve head, proper porting, 28 mm carb, here's the result :



would pass the 20hp mark with proper jetting.. still a bit rich.. will be back soon..

For comparison DYNO RESULT :


150cc YAMAHA VIXION / FZ150i




225 cc YAMAHA SCORPIO

 
H

hass

New Member
Thanks for the result Haen :wink: .

I'm impatient to test this cam .

The difference with my motors , I use the injection 28mm and I welded one nut to the exhaust and I use one o2 sensor , I corrct manualy with the power commander my AFR .

The only one problem, I'm limited with the oem Ecu to 10000rpm :evil: .

I think I goes mod my block to come to 6.5 bar like the second motors .
 
J

jeftronix

New Member
very very nice and brave experiment Sir traxx..just to share my set up about this "squish banding" I am using 61mm block with "NO GASKET" at the top and even the bottom of the block!! yes only threebond gasket maker..
valve clearance is .9 for intake and .15 for the exhaust.. (you cannot go further with the clearance this is the MAX) take note "RACING CAM" is intalled if someone want to copy this set up be sure to install also "RACING VALVE SPRINGS" i have used this set up in Carmona race track and touring...and also b4 I forget I am also using BRT hyperband C.D.I.....I also have removed the "BALANCER OR flywheel..so in other words this engine is very high revving....SACRIFICE is vibrtion ang knocking noise..but the power is...... just sharing my set up...thanks for reading...
 
G

ghotichooder

Veteran
errr...i would like to ask something...if i shave my block...and i dont want to remove decompression assy is it possible the valves not collide with top of the piston?
 
THE TURKEY

THE TURKEY

Super Veteran
jeftronix said:
very very nice and brave experiment Sir traxx..just to share my set up about this "squish banding" I am using 61mm block with "NO GASKET" at the top and even the bottom of the block!! yes only threebond gasket maker..
valve clearance is .9 for intake and .15 for the exhaust.. (you cannot go further with the clearance this is the MAX) take note "RACING CAM" is intalled if someone want to copy this set up be sure to install also "RACING VALVE SPRINGS" i have used this set up in Carmona race track and touring...and also b4 I forget I am also using BRT hyperband C.D.I.....I also have removed the "BALANCER OR flywheel..so in other words this engine is very high revving....SACRIFICE is vibrtion ang knocking noise..but the power is...... just sharing my set up...thanks for reading...
Click to expand...
i used this set up also and my bike got blown up.becoz of over revving...how can we avoid to blown up our engine when using this set up for drag and longride sir??? :idea: :idea:
 
sniper31

sniper31

Super Veteran
Supposed to be i will rem0ve only the base gasket, no shaving on the block. Is there any high compression attain? How many mm the original base gasket? Pls i need ur answer. Thanks!
 
J

jay woo

New Member
I think some confusion exists between the squish band and compression. They are closely related but you can have the same squish band clearances and different compressions. Shaving the cylinder will change the compression, squish band, cam timing, piston to valve clearance and spark requirements. If people are shaving the cylinder to raise compression then spray some WD40 on the piston and valves and use some modelling clay to see what the clearance is between the valves and piston and the cylinder head and piston.

Have a look at the manual for the racing parts on the link below ad it will show squish. I am not suggesting that this is the correct value of squish to run.
Manual
 
Kenshi

Kenshi

New Member
Can we consider removing the base gasket a "Squish band" or do we really need to shave off a few mm in the block or head to call it a squish band?
 
macoolet

macoolet

Super Veteran
Kenshi said:
Can we consider removing the base gasket a "Squish band" or do we really need to shave off a few mm in the block or head to call it a squish band?
Click to expand...
they do differ but i would answer you yes,because their purpose is the same,to increase the compression,but for me it's better to squish the block so you can still use a base and a head gasket,it's much safer "oil leaks" than removing the base gasket or the head,but choosing between removing the head and base gasket,choose to remove the base,because the combustion and the water passage is more delicate in the top part of the block.as for using a higher lift and longer duration cam,valve pocketing may solve the problem
 
Kenshi

Kenshi

New Member
macoolet said:
they do differ but i would answer you yes,because their purpose is the same,to increase the compression,but for me it's better to squish the block so you can still use a base and a head gasket,it's much safer "oil leaks" than removing the base gasket or the head,but choosing between removing the head and base gasket,choose to remove the base,because the combustion and the water passage is more delicate in the top part of the block.as for using a higher lift and longer duration cam,valve pocketing may solve the problem
Click to expand...
i see.. this makes me think hehehe i think i'll try to remove the base gasket first and see how my smx will perform. Thanks for the info macoolet.
 
macoolet

macoolet

Super Veteran
Kenshi said:
i see.. this makes me think hehehe i think i'll try to remove the base gasket first and see how my smx will perform. Thanks for the info macoolet.
Click to expand...
No problem,just make use of a better tri-bond sealant and avoid to cover up the passages..good luck
 
rpenera

rpenera

New Member
Admin somethings wrong with the link it says: The requested page could not be found.
traxxas-modifier said:
The cylinder head and cylinder block is removed


This is what the piston looks before the squishband
Lots of CARBON!!!



Heres the space between the Top surface of the piston
and the top surface of the block. theres around 1.7mm of space.
We will shaveoff 1mm on the UPPER portion of the block.


The cylinder block is then brought to machine shop. the block is installed on the lathe machine.
ITS VERY IMPORTANT that the machinist will align the block properly to the machine so that the shaving off is perfectly flat
and aligned. So go to your trusted machine shop only.

we will shaveoff 1mm on the UPPER PORTION of the cylinder block.



shaving off on progress


Partially shaveoff cylinder block.


Finished shaving off 1mm to the block.
removed any debris in the block. be careful when handling the block. make you you will not scratch the inside of the block.


Its time to put it back to the engine


This is now the final result when Piston is installed.
piston is on TDC (Top Dead Center)
notice that the space between top surface of piston to the top of the cylinder block is so small already!! :)


another picture of it


clean the piston using gasoline or carb cleaner.
its effective in removing carbon deposits


Put everything back.
On my setup, The TOP GASKET and BOTTOM GASKET is installed.


voila! test it and always observe for any leaks.
make sure you have torque wrench so that there is equal tightening of the stud bolts to prevent leaks.

again DONT BLAME ME if something goes wrong to your engine.
This mod is just to show that shaving off 1mm to your cylinder block is possible and so far after 5000km
of usage, no problem occurs.

Enjoy your much powerfull, high compression T135 Engine :D
Click to expand...
Admin any modification on the piston? does it require a valve pocket? I will be using a faito low cam. recommendations please. :)
Thanks
 
macoolet

macoolet

Super Veteran
rpenera said:
Admin somethings wrong with the link it says: The requested page could not be found.

Admin any modification on the piston? does it require a valve pocket? I will be using a faito low cam. recommendations please. :)
Thanks
Click to expand...
you answered your own question my friend;)
 
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