Yamaha Blaster HEMI High Compression Performance Head
for +3mm Vitos Stroker Crankshaft
Fits all years (88-06)
Unlock the Full Potential of Your Blaster
This precision-machined high-compression head is one of the most effective and affordable upgrades you can make to your Blaster. It delivers massive horsepower gains — taking a stock engine from around 18 HP into the mid-30s range — all without the need for carb rejetting or other supporting mods. Just bolt it on and ride. For the price, nothing else comes close.
The item you receive may vary in appearance from the listing photos. This is completely normal and expected. Rest assured, every part goes through the same rigorous quality standards and precision processes before it ships. If you're the kind of person who judges a book by its cover… we suggest you try reading a few pages first.
This head is intended to be used with a +3mm Vitos Stroker Crankshaft. Normally you would need to use a 1.5mm thick aluminum spacer under the cylinder between the case so that the piston doesn't crash into the head. This is not ideal since it alters your port timing. This head design has the clearance already machined into it so there is no need to run the spacer. A genuine Yamaha OEM base and head gasket should be used with our head to achieve the proper squish and port timing.
Technical Specifications:
Combustion Chamber Type: HEMI
Combustion Chamber Size: 20cc
Squish Angle / Area: 11 Deg 50%
Optimum Bore Size: 68mm
Stroke: 60mm (no cylinder base spacer)
FAQ's
Difference between Toroidal and HEMI chambers? Toroidal makes better mid-range torque and self-limits over-revs. The HEMI makes better peak power and RPM.
Will I need to use race fuel? No, you can use standard 93 high octane pump gas.
What base gasket will work with this? Please use a new Yamaha OEM base gasket (p/n: 3JM-11351-02-00) to achieve the proper port timing.
What head gasket will work with this? Please use a new Yamaha OEM head gasket (p/n: 2XJ-11181-00-00) to achieve the proper squish.
Will this require jetting changes to my carburetor? No, since this modification only changes the burn of the air/fuel mixture and not the flow. No jetting changes are needed.
What bore sizes will this work with? Any of the standard cylinders (non-BBK 240cc) will work (66-68.25mm). Although best performance will be achieved with a stock 68mm bore.
There's some pitting in the chamber of the head I received. This is normal and will not affect the performance of your head. The voids are from the original casting process of a stock head.
Can you make custom heads to my specific needs? Yes we can alter any of the technical specifications listed above to your request. We can also machine Toroidal style chambers. We can also machine the head to accept a +4mm or +6mm stroker crankshaft. We also offer case trenching services for +4mm and +6mm stroker crankshafts.
Note: The listing pictures are for reference only. Since we have (in the past) re-machined used heads some will look slightly different than others as far as appearance. However the machine work will be identical to what is shown in the pictures.
Will Ship Within 24 Hours of Receiving Payment
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