I have a new style Predator hemi engine and I am very confused about at kinder heads. I have been reading about gx160 head usage in clones but is this advantageous in this engine? I also see 18cc heads....I guess I am just confused about head compatibility of this engine. Or am I best off having my existing head machined down? Any help would be great.
Hemi Predator cylinder head confusion
I thought the hemi head added about 1/2 hp more than the normal? That's about what you'd get out of a 14cc head, isn't it? I have a hemi motor on my doodle, and I have a fairly modified clone with a 14cc head on a kart. I'm not going to swap heads on the hemi. I think I'll focus funds on other parts.
What have you done to your hemi motor? There is a lot that can be done to improve them before swapping out heads. What is your hemi on, kart or bike? Are you gonna race it?
What have you done to your hemi motor? There is a lot that can be done to improve them before swapping out heads. What is your hemi on, kart or bike? Are you gonna race it?
this is what i did with mine and tons of info in the thread
http://www.oldminibikes.com/forum/h...ines/86170-predator-212cc-hemi-upgrade-s.html
http://www.oldminibikes.com/forum/h...ines/86170-predator-212cc-hemi-upgrade-s.html
the benifit of the hemi motor is the fact that it has a nice light flatop thin ring piston, the bottom end is just like a regular clone as far as cam journal size and side cover gasket but it has the added bore and stroke so it is 212 cc's. the head stock flows a slight bit more than a standard clone head but it is a open chamber 22-24cc chamber. The head has a lot of potential for modification to the ports and chamber.
All of the clone and honda heads will fit the hemi predator, a 14cc head stock will add about 1hp. The 18cc head will fit and add about 1/2hp, a stock clone/old predator head is 22cc. I've seen people mill clone heads 100 thousandths but pushrods have to be changed to get the valve train geometry right. I have a well modified hemi motor with a 14cc head and its a screamer.
I don't think you can mill a hemi that much as the canted valves have less clearance to the flattop piston. LScustom bought a modded NR hemi that was milled a bit but I don't think you can go .100 and then use a higher lift cam without notching the pistons. I am trying to weld one up to get more squish and compression .
I don't think you can mill a hemi that much as the canted valves have less clearance to the flattop piston. LScustom bought a modded NR hemi that was milled a bit but I don't think you can go .100 and then use a higher lift cam without notching the pistons. I am trying to weld one up to get more squish and compression .
I see I am not alone in my thinking how and where to put the weld
What are you using to put the bead down in there?
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I don't think you can mill a hemi that much as the canted valves have less clearance to the flattop piston. LScustom bought a modded NR hemi that was milled a bit but I don't think you can go .100 and then use a higher lift cam without notching the pistons. I am trying to weld one up to get more squish and compression .
i think you are on to something welding it up! and re working the chamber...
im having better luck with the 14cc i just put on mine, are your mods more aggressive than where i am at with the same head?... thinking about playing with the cam too, but trying the mikuni with the black mamba first to clear up the issues im having getting the carb to act right... the carb has been too sensitive for me, where i cannot adjust it properly