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Discussion Starter · #1 ·
I found this half built engine in a shoe box in the trunk of one of my cars decided to finish it up this weekend.

The engine was half put together but I completely disassembled it and started finishing up what I'd started.

I went to town on the feed ramp and feed ramp area of the crankcase
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Discussion Starter · #2 · (Edited)
The only modification I did to the Piston was put a window in it this time around I modified it inside and out I polished the top of the piston reshaped the bottom of the piston and the skirt I also break edged the skirt internally ( knife edged ) and ground out the casting lines to make the window function properly.
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Discussion Starter · #4 ·
Modified the crankshaft counterweight to help feed the ramps better
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Discussion Starter · #5 ·
I'm starting to see an engine go together 馃槂
I have already modified the cylinder adding a boost port and opening it up
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Discussion Starter · #6 ·
I have already modified the Reed stopper and read plate as well as the intake manifold.
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Discussion Starter · #7 ·
I'm going to go ahead and revisit the carburetor it's 95% of the way modified the only thing I'm going to do to it is open up the back side just a tad
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Discussion Starter · #8 ·
I definitely want to keep the stock air filter it helps me plead my case for anybody that's unsuspectingly wants to race me that it's a stock engine and that I have not modified it in any way but I do have to drill holes in it because this engine is definitely going to suck a lot more air than stock
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Discussion Starter · #11 ·
I went ahead and lightened the flywheel by removing some fins and unfortunately I'm out of rocket keys so I ended up having to make one myself
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Discussion Starter · #16 ·
The reed stopper in the carburetor are looking pretty good. Good job!
Thank you. I opened up all the ports unfortunately I didn't have a stock cylinder to hold next to it but if I did you would definitely see the difference also if you flip over a stock piston you will notice a lot of blunt flat edges that does not matter at all with a stock piston but once you add a window the unwanted turbulence from these edges lowers the efficiency of the flow throw the window into the boost port .

Edging the crank is to help streamline the engine and also assist in directing the fuel charge towards the feed ramps.

Basically with these engines anything that can help the flow path is going to be a big improvement

Lightning the reciprocating mass also helps improve the balance factor creates less shaking and makes for a snappier faster revving engine
 

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Engine RPMs have a lot to do with what flywheel timing key you use. If your eng runs 9,000 or below a rocket key is good, but its more stock or lightly modified engines. If you can get to 10,000 plus rpms better to run stock key, or might have to retard it. Reason, with the R/Key the coil will fire before the piston gets to TDC, better a little after. Firing to soon it will pound the top of the piston and hammer your rod end bearing. On a Cag engine that bearings is its weakest point.
 

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Discussion Starter · #20 ·
If you hold up your stock part next to my pictures you will notice a huge difference in the shape and opening size of the intake manifold.

I also modify the Reed stopper in a similar fashion to Wannaberacing
 
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