Box Stock

Clone 212 help.

B

bagger

New member
I am new to this. I have a clone hemi and a non-hemi. The hemi has a .009 head gasket , larger carb, pipe, and a 6-degree key. Have I done the right things?
This is on a mini bike.
What are the advantages of running th hemi head on the non-hemi block? I would like to be about 11 to 1 comp.

Thanks,

jim
 
Its not going to give you 1 hp .
If its already in I would leave it be.
Just be sure you torqued the flywheel nut good .
 
A bigger carb , you changed out the air filer assembly ?
From what you have desribed your there . Next step is billlet flywheel , cam , springs , port work and rod .
 
Air filter was a given...Thinking of the f/w and rod.
How does one go about boring one? Is it done with a hone? I knew of a machine shop that did that on small engines.
I guess I need to see a head that has been reworked. I have done port work on Cushmans and Mustang engs with quite good results.

Thanks,

jim
 
Kart shop is best bet for boring unless you have a ridgid hone .
Porting is basic , until you go to the nth degree .
Plenty of pictures on port shapes here abouts plus the web .
Search function on top right corner of page , little magnifying glass symbol.
 
After holding 2 different heads in hand, I believe that a non- hemi head with a flat top piston will yield the best compression. Correct me if I'm wrong and please tell me why. I know the hemi head has a larger intake valve.
 
Combustion chamber size. I have not measured it, but it looks smaller.

3 things make hp in internal combustion engines. Cam, compression, and carburation or fuel injection. That is what I have learned over the years. Does it change in these small engines?

I am just trying to learn this eng. I have very little experience with small engines. The things I am trying to do have nothing to do with racing. I want a higher h/p eng for my minibike. Looks to me like a small combustion chamber with a flat top piston will give the compression I want. Which head has better flow numbers, ported, and unported?
 
Correct it has a smaller chamber .
The same basics still apply .
Flow numbers might be on here i do not know them off hand .
 
My eyes are not failing.
Just trying to learn the ins and out of this.
I put a head on my belt sander and milled/sanded quite a bit off. Then put it on a glass plate and find it is absolutely true. Now to use a finer grit and smooth it up.

Thanks ,

jim
 
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Fuel injection in itself will not make more horsepower .
It is better at giving the optimum fuel air ratio in more conditions .
Cam alone maybe , it is actually the increase in volumetric efficiency the cam may provide .
Maybe in reality VE is the only thing that improves power .
Everything else just helps that main goal .
Fuel type would be another thing though it may be considered a power adder .
When Fred got Barney to help they went faster :giggle:
 
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i have a 212 Hemi with a .397 billet cam, .065 long rod, slipstream flywheel, tct "carb", fully ported and polished with stainless valves (27mm-25mm) and billet spring retainers. Should I look into stroking and boring my block and put a non-hemi head on with 1.3 gauge rockers with chromoly pushrods and billet lifters. running a 4bt Cummins turbo with EFI and nitro meth soon. any other suggections? inta is hulkbuster10103 if you want to see the little build
 
HB10103 said:
i have a 212 Hemi with a .397 billet cam, .065 long rod, slipstream flywheel, tct "carb", fully ported and polished with stainless valves (27mm-25mm) and billet spring retainers. Should I look into stroking and boring my block and put a non-hemi head on with 1.3 gauge rockers with chromoly pushrods and billet lifters. running a 4bt Cummins turbo with EFI and nitro meth soon. any other suggections? inta is hulkbuster10103 if you want to see the little build
Click to expand...
That's some serious turbo for a single cylinder powa.
 
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