Greyhound Clone Build for a 2005 Ty-Rail Gokart

#41
Question: Is a CL-1 original cam/1.3:1 rocker/26lb spring an advisable combination?

Another question: The NRR 230 series. It claims "30* more duration than stock." I measured mine at 195* @ 0.050". What duration are their cams actually?
 
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#42
Well I'm gonna pull the trigger on the Burris rockers. Russel confirmed the 230 series has 230* @ 0.050". Not sure if I should go with the CL-1 or a 230 0611. Should I do a poll?
 
#43
Question: Is a CL-1 original cam/1.3:1 rocker/26lb spring an advisable combination?

Another question: The NRR 230 series. It claims "30* more duration than stock." I measured mine at 195* @ 0.050". What duration are their cams actually?
What is the max RPM you would like the engine to see? Reason I ask is because usually when someone wants to use 26lb springs they are going for 7K+ RPM, and usually have a more serious cam to go with it.

I like the CL1 and may go with it when I get around to my clone. But I don't plan on seeing more than 5K RPM's and may even use stock springs. Isn't the CL1 a lower RPM cam, about 5500 and under?
 
#44
What is the max RPM you would like the engine to see? Reason I ask is because usually when someone wants to use 26lb springs they are going for 7K+ RPM, and usually have a more serious cam to go with it.

I like the CL1 and may go with it when I get around to my clone. But I don't plan on seeing more than 5K RPM's and may even use stock springs. Isn't the CL1 a lower RPM cam, about 5500 and under?
I plan about 6800-7000rpm. I've heard about 5500 from a CL-1. The 1.3:1 rockers will make it about 295 lift, 226* duration. The 230 0611 will be 295 lift, 235* duration. Are there any downsides to a 26lb spring over the 22lb?
 
#45
Oh crap... Forgot about the rockers. Not sure about those spring differences. Maybe others can help. I guess the thing to find out is where do the 22lb springs top out RPM wise?
 
#46
I rechecked the deck height. I got 0.032". For the reciprocating assembly I will (eventually) do a GX160 UT2 piston and an ARC 3.403 rod. That will put me at 0.012" deck height, 0.021" squish, and about 9.6:1 compression with a stock unmilled head. I can mill the head at home if need be.

For valvetrain I'll go with the NRR 230 0611 with Burris 1.3:1 rockers and the OMB stock size stainless valve kit with 26lb springs. Chromoly pushrods of course. For fun I might make this for the guide plate: Guide Plate, Free Floating w/broze bushing, 3/16" - GX200, GX160, & 6.5 Chinese OHV

For right now I decided to do the governor and oil sensor deletes because I screwed up the governor. I was turning the flywheel by hand and it sucked up the arm and pretty much ruined the mechanism. Damn that thing's strong!

I just got confirmation that I will be starting my summer job at BBraun tomorrow. That should speed up this build.:thumbsup:
 
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#47
First week on the job and I'm loving it!:thumbsup:

I made a flywheel puller because my harmonic balancer puller was too wide for the PVL. Take some bar stock and some bolts:

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Drill/tap some holes, spend a few minutes in the sand blast cabinet, finish with a coating of PTFE spray:

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Grind a milder end on the forcing screw as to not damage the end of the crank:

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Assemble:

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And presto!

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#48
Kudos to all who are still following this slow build. Sometimes I put myself to sleep.:sleeping:

I just tore the engine down except for the rod and piston. I'll save that for when I do the Z4M swap.

I removed the oil sensor (that never worked from purchase anyway) and governor using the Grey Goat technique. I left the ninja star for now until I change the rod and piston.

The next order of business is a catch can. I have some neat ideas for it.
 
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#52
About 2/3rds done with the breather/oil control doohickey. I didn't take any pictures as I was machining it because it was 100F in the shop and the Kodak didn't appreciate it. There are three baffles in the center. They all look the same but are clocked 120* and are separated 3/8" by spacing rings. I plan to make a Delrin cap for the top so I can use this thingy as an oil fill instead of fooling around with the almost horizontal stock filler. Enough of me, the pictures can talk:

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Catch Can Plumbing gif.gif

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#54
I designed the cap in Fusion 360 so I could see how it looked before I put HSS to plastic. After I got it right in CAD I decided to just 3D print it. It works fine but the support material on the chamfer was beyond impossible to scrape off. Because of that I will be making a Delrin cap anyway.

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An O-ring fits into the groove around the thread:

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At this point the flash on the ancient Kodak lost a couple hundred IQ points. My headlamp is standing in until I get it fixed.

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The support material as mentioned earlier:

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I had to change up the nipple on the filter adapter to run 1/4" ID hose:

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Forgot to mention it in the earlier post but the cap that will be welded to the bottom of the mystery can has a 30* countersink to funnel oil back into the drain. I am waiting on the stainless TIG rods to come in so my neighbor can weld it.

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#56
It's a good day! NR dropped off a box of horsepower:

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From left to right is a 3.403" ARC rod, an NRR 230 0611 cam, a Honda GX160 UT2 (Z4M) piston, and the overpriced rings for it.

To make the +0.100" rod, ARC offset the wrist pin bore. I expected the beam of the rod to make up the extra length but what they did makes more sense:

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Comparing the stock cam (left) and NRR 230 0611 (right) side-by-side. The two cams have identical base circles. The piston is there to get my potato to focus on the intake lobes:

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There was a recent thread about breaking in an NRR cam. Here's a picture of the label that describes the process:

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#57
Got right to work on the rod. It's pretty astonishing my crank is within ARC specs. They say 1.180" +0/-0.0025" diameter and 0.0005" out-of-round. I clock in at an average of 1.1798" with a total 0.0004" out-of-round. Woo-hoo!

Next they tell you to polish the crank. Mine seemed like a finely machined surface, not polished. I'm not too sure how they do it but here's how I did it. I chucked the PTO in a lathe and put it in it's lowest backgear. Next I wrapped scotch-brite around the journal and let it pull my hand back and forth. I must say, it's a pretty good workout.

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I only did a light hit of the scotch-brite before going to crocus. It will take quite awhile to get a good polish running 40rpm:

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Now it's a bit cringy to have your hands repeatedly being sucked in close to those counterweights. That's where the vise grips come in. Now I can run 75rpm with confidence.

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I had to put it on hold when the rain/hail started coming down in the evening. It's not fun to machine when the lights flicker and you can't keep the machine running.
 
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#58
Finished the crank polishing. More crocus and finished up with some 15 micron diamond paste. It's good enough for me:

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After polishing I re-measured the journal and now I get 1.1798" with 0.0002" out-of round. I couldn't ask for any better even if this was a Honda crank. Then I had to measure oil clearance even though I don't have plastigauge:doah:. I ended up doing it the old-fashioned way with a telescoping gauge and micrometer. The target was 0.0025"-0.003". I got exactly 0.0027" every time. I'm glad Karma is taking it easy on my first build...

...that is until I go to put the rings in the piston. The oil ring separator and top comp ring wouldn't fit in their grooves. Turns out my own cheap :asshole: is to blame. On the NRR page for the piston it says "for standard size use -801 rings" and "for oversized pistons use -003 or -004 rings." The standard piston on that page is a -800, meaning it takes the newer, thinner, -801 rings. The oversized pistons sold from that page are the older -000 type, meaning they need the older, thicker, -003 or -004 rings. NRR only sells the -801 rings in standard size but the -003 rings can come standard through +0.030". The -003 rings are also about $5 cheaper than the -801. Thinking the standard -003 would be the same as the -801, I bought the -003.

Long story short if anybody needs a set of 13010-Z4M-003 rings, I'm your guy!

A picture of the amateur hone on the bore:

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#59
As of now ARC is out of stock of their 25/24 stainless valve upgrade package because they are out of the 25mm valves. That means I'm stuck with stock valves for awhile. I will run the NRR cam with an otherwise stock valvetrain (keeping below 5k) until ARC gets the next shipment.

I was also thinking about a tach. After searching for quite awhile, I remembered the Trail Tech Vapor which is just about the standard for tricked-out GY6 vehicles. Turns out they make a TTO series tach/hour meter so I'll give it a try. The link: https://www.trailtech.net/tto-1
 
#60
Got my (correct) rings and some other goodies from OMB. The difference in the part numbers for the rings with bad on left, good on right:

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I decided to insert the piston through the inside of the crankcase instead of through the top for two reasons. One, the rings would have to jump over a step of aluminum before seating into the cast iron sleeve if going through the top. Two, the bottom of the sleeve has a chamfer in it specifically for installing a piston. Along with that you only need to use your fingers to install through the bottom; no ring compressor. I thought of this because of the same trick on GY6's but it's no secret. This hopefully explains my point:

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A random picture of the shear beauty:

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The side cover gaskets I ordered apparently aren't for my engine. They fit well except for one hole. But they do work if you make your own hole:

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My neighbor did not weld my canister yet but he is a hustling man. I ran the lines for the oil thingy but plugged the 1/4NPT elbow for the canister and left a loop for the hoses that will connect to it. Here's the look:

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I drilled the main out from 31 to 35. I did manage to get it together in one evening so I filled the bowl with fuel and it cranked the first pull. :scooter:
 

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