14cc head help

#1
I have a 212 hemi predator and I just put a stock 14cc head milled .65 on it with the champion rockers 1.1 the ones they have on smallenginecams.com I put the valves out of my predator head in the 14cc head, here are my questions what size push rod do I use, and can I use a .16 copper gasket.
This is my first time useing one of these heads
 
#2
If you have the hemi block that means you have a flat top piston. You can use any gasket you like as there is no way the piston can ever interfere with head or valves.

As for the push rod length I've never used this combination myself so I couldn't tell you if standard ones will work. Just mark the top of your valve like any other engine and see what the wipe pattern is.

Coxy.
 
#3
If you have the hemi block that means you have a flat top piston. You can use any gasket you like as there is no way the piston can ever interfere with head or valves.

As for the push rod length I've never used this combination myself so I couldn't tell you if standard ones will work. Just mark the top of your valve like any other engine and see what the wipe pattern is.

Coxy.
Alright thanks
 
#4
Why did you use the vlaves from that head in the 14cc?

Are they the same size?

You are running a .065 milled 14cc head on a 212cc engine with a flat top....

What is your clearence from the piston to the head?
Your piston should be at least .015 in the hole for safety with the gasket you want to use.

DO you know what your compression ratio is?
15:1 or more with that head depending on how everything stacked up.
What are you going to burn for fuel?
 
#5
Maybe methanol or as us southerns like to call it alcohol, but with out the right timing and valve train set up....it sounds like a big explosion to me. :scared:
Good Luck and be safe young man !
 
#6
Why did you use the vlaves from that head in the 14cc?

Are they the same size?

You are running a .065 milled 14cc head on a 212cc engine with a flat top....

What is your clearence from the piston to the head?
Your piston should be at least .015 in the hole for safety with the gasket you want to use.

DO you know what your compression ratio is?
15:1 or more with that head depending on how everything stacked up.
What are you going to burn for fuel?
Yes I'm pretty sure they are the same size I do not know my clearnce
I do not know my compression and I'm running 93
 
#7
You milled the 14cc to make it even smaller? I'd definitely be careful with 93. You may be able to use some octane booster, but I'd consider running alky. I'm not sure on the rod length. Are the valves you are inning stainless steel? Which cam are you running, and what size valve springs?
 
#8
You milled the 14cc to make it even smaller? I'd definitely be careful with 93. You may be able to use some octane booster, but I'd consider running alky. I'm not sure on the rod length. Are the valves you are inning stainless steel? Which cam are you running, and what size valve springs?
Do I need to run a different gas?
The valves are stock and the cam is stock
Valve springs are 18lbs
 
#9
YOU Are on the Quick Road to problems that YOU are not Ready for Sir....... Dave:shrug: PS your push rods are going too Long
 
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#10
Do I need to run a different gas?
The valves are stock and the cam is stock
Valve springs are 18lbs
I'd hit google up and see what you find. I'm sure there is some good info out there. I'm not an expert, and I can guarantee there are some guys on here that know there stuff. Hopefully they'll correct what I get wrong, and they'll share their knowledge with you.
High compression engines can cause the fuel to ignite prematurely. Alky has a lower ignition temperature, and it runs cooler too. That's why engines designed for racing use higher octane fuels or alky. You want your spark plug to ignite the fuel, not the compression of the fuel and air. You want the fuel to ignite at the top of your stroke to maximize the power (although some do play with their timing a bit). If your fuel/air mixture is igniting to prematurely, you're going to be fighting to get the piston back to the top. It's kinda like trying to push the pedal of your bike down before it is back to the top in a fixed gear application (ie. no coaster brakes and no freestyle bikes).
Diesel engines don't use spark plugs. I didn't know that until a year or two ago. The diesel fuel is less refined, and I think it ignites with just the glow plugs and compression. I don't totally understand the science behind it, but I'd love to learn. I've never owned one or torn one apart.
I think most cars run around 8:1 compression. Some are less, I'm sure. As you run the motor, friction destroys the rings and cylinder wall, which in turn lowers the compression ratio. This means you'll lose some compression as you run your engine too. Most racing engine builders "freshen up" their motors often. High RPMs kill motors if you don't care for them and set them up properly.
Like I said, there are some really smart, experienced guys on this site, and I recommend listening to them. Experience with this stuff is valuable. One conversation with someone who knows there stuff is worth more than a weeks worth of research on the web. I'm hoping someone will chime in and explain this better (and more accurately) than me. Be polite and humble if you are given the chance to sit down and learn from them. You'll not regret it if you do.
 
#12
I put the 14cc head, but mine came with valves and rockers. It was basically a a bolt on application for me. I did not mill it. I'll be upgrading my rods to chromoly rods, and I'll go with stainless steel valves and 26lb springs when I do. You won't need to do the rods unless you are running an aggressive cam and 26lb springs.
 
#13
I put the 14cc head, but mine came with valves and rockers. It was basically a a bolt on application for me. I did not mill it. I'll be upgrading my rods to chromoly rods, and I'll go with stainless steel valves and 26lb springs when I do. You won't need to do the rods unless you are running an aggressive cam and 26lb springs.
I'm starting to think that a 14cc milled .65 was a bad choice
 
#15
i've been following this thread but i am still confused over your head.

did you take a 14cc head and mill an additional .65mm, or .065" off
of it? please respond using either mm or inches.

thanks,

phil
I don't know if it is mm or inches I bought the head from a local minibike store milled 0.65 thousands
 
#19
ok, so if the shop shaved an additional .00065" off the head
the capacity of the head was reduced by only .098cc.

so if i am not nuts, and please correct me if i am, you should
have a 13.9cc head.

the volume calculation i used assumed a straight wall inside
the head. if its angled you have less cc's.

as it is you have about a 15.2:1 compression ratio. adding a
1mm head gasket would add about 3.85cc, or 17.84cc's total.
the compression ratio would be 11.9:1 which is a bit more
manageable for your application. this lets you use pump gas.

just my two cents :thumbsup:
 
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