-40%
PREDATOR 420 “HEMI” HEAD **RACING ** WELDED,PORTED, GUIDES,
$ 448.27
- Description
- Size Guide
Description
HONDA GX390 / PREDATOR 420 “HEMI” HEAD **WELDED,PORTED,BRONZE GUIDES,POLISHED. Condition is New.FAST SHIPPING ***** expedited 3 day *****
• COMES WITH VALVES ( “ SI VALVES “STAINLESS STEEL )
• COMES WITH ROCKERS ( SHAFT MOUNTED )
NEW Predator 420 “HEMI” head
Rare piece “not sold anywhere online” !!!
Impossible to find these heads , let alone a brand new modified racing head !
Welded chamber to increase compression
Hemi head design allows the intake charge to get supercharged during valve overlap with proper cam design and the hemi head is the best at this . This makes the hemi head such a great tuning option .
Large welded quench areas are now created. This creates “ the quench effect” which is tight areas between the piston and the head squeezing jets of air that create greater fuel mixture motion. This creates higher horse power levels with increased fuel efficiency.
Radius shaped bowls to increase cylinder fill and velocity around the valve. Documented on the flow bench with smoke and refined shape produces a visible champagne glass flow travel path around valve perfectly filling the cylinder ..
This head comes with SI valves stainless steel valves ( valve Head polished to a mirror finish) 38mm intake and 34mm exhaust valve, bronze guides , shaft style mounted rockers.
Clearance and transition to spark plug is refined and shaped perfectly for better burn and more power. Spark plug position within the head is extremely important in creating power. in this head the position has been changed and brought closer to the optimal position.
Polished chamber keeps carbon off the chamber and helps keeps detonation down increasing power potential and eliminating the need for expensive high octane fuels .. ** with 420cc engine, will run on 93 octane of extremely well on methanol.
Multi angle valve job (5 angle seat cuts) improves flow in all rpm ranges ** extremely effective at improving flow in low rpm’s ... and that’s the most important area to improve flow thru. Twice as important than high flow since the valve passes this area twice during the cams lobe profile.
Bronze guides installed and reamed and honed to exacting tolerances. This keeps the valve much more stable at rpm’s and cooler valve temps . Allowing lower octane fuels to be used . Notice the trend of optimization towards head overall design.
Guides bullet shaped prior to installation on lathe to shape that I found flows best on the flow bench
Ported intake and exhaust ports (stage 3 ) our highest stage. These port designs are developed on our flow bench . THAT WE ACTUALLY HAVE AND USE DAILY !!!!!!!! And I guarantee it will flow and perform as good as it looks . This head is truly a super rare piece !!
Polished exhaust port to a mirror finish. Keeps carbon build up to almost zero !
Hemi head has cantered valve angle that is IDEAL for flow and for increasing cam performance by increasing the way the “exhaust driven , intake supercharging effect” takes place ... watch my videos on the 5 th cycle to see how this effect is the key to HP. And is the tuning effect !!!
This head is created by Paul’s karts , Paul’s karts channel can be found on you tube and offers build information and helpful facts about engine building . The contact information for my shop is also listed on all new videos put out this year .. feel free to message question concerning fit of this product ..
This price reflects all carrying fees, head purchase, shipping fees associated with assembly, e bay listing fees , and all labor in producing and listing this head .
Thank you