Hemi Predator Build #2

[bob58o]

Ordered the ARC top plate that fits the Hemi Predator.
I decided on the DJ-1146 instead of the cheaper economy plate. This one looks like it gives more clearance under it. Since I had trouble fitting the gas tank with the 90* barbed fitting I added to the top of the block, I wanted this one to give extra clearance. I don't know it will clear, but I'm hoping.

Also ordered the 2* degree key so I can turn back the timing on the 34* flywheel to 32* BTDC. A lot of people don't like using keys, but I don't have timing light / degree wheel. I might use the key to mark the position of the flywheel on the crank and then torque the nut without the key.

How bad is it to use an impact wrench to torque the flywheel wheel nut on? I haven't tried rope in the spark plug hole yet, but nothing else has made this task very easy. I've interlocked some wrenches and put them through the starter cup, but felt that was going to give. I tried ratchet straps , but the HF ones I had didn't work great. KF has some good ideas on his video, but I don't want to buy TC parts or weld up a plate with key.

The HF electric impact wrench seems to do OK, but not really sure how tight it torques it or what the worst that can happen

Delivers 230 ft. lb. of max torque
Rocker switch for one hand forward/reverse
Rugged cast aluminum nose with lightweight high impact housing
High power 7 amp motor


http://www.arcracing.com/dj-114x-arc-top-plate-throttle-station/
http://www.nrracing.com/product-p/nrkey.htm

 

[bob58o]

Exhaust is here.
A little gasket matching, used exhaust studs and nuts from old head, and....

 

[bob58o]

Alright...
I didn't have the specs before, but I measured them so I've got them now.
More exhaust diameter GAB....

~18" total length
4" stage 1 1.00 OD
8" stage 2 1.125 OD
6" stage 3 1.335 OD

CSA of pipe = ((Cylinder Volume * RPM) / 88,200)
212cc = 12.94 cubic inches

The pipe is made of 0.065" thick steel.
ID is ~0.87" then ~1.00", then 1.25"

1.25 " Diameter = 1.22 sq inch CSA
1.00 " Diameter = 0.79 sq inch CSA
0.87 " Diameter = 0.59 sq inch CSA

1.22 = (12.94 x RPM) / 88,200
RPM = 8,316

0.79 = (12.94 x RPM) / 88,200
RPM = 5,385

0.59 = (12.94 x RPM) / 88,200
RPM = 4,021


Clutch engagement will be at 4k, so that matches the first stage.
Most of my riding should be done around 5.4k, which matches the 2nd stage.
I'll never pull to 8400 RPM, I don't think. So the last stage is a little big. I'm expecting max RPM around 7500.

Not really sure how the three stage exhaust works. My "go to" formula doesn't account for multiple stages.

It should be fine! Not sure there was a better option???? I don't know I just make educated guesses. It looks like it should scream. Can't wait for the flywheel.

 

[bob58o]

Mocked up the fuel line with the stock tank and blower housing. Sometimes this is tricky. Hard to fit the filter and shut off valve in there. With a stock carb it is even more difficult. The short intake and bends makes some line difficult to bend right to fit.

It's a mix of 1/4" and the stock 3/16". Filter and shut off take 1/4, tank takes 3/16, carb seems somewhere in the middle (6mm?). I heated the 3/16" to make it stretch when I needed it to.

If you have been counting along, you would know I am now up to 15 hose clamps on this build. With the header support bracket, that will be 16.

 

[Noseoil]

Looking good Bob, plumbing looks like it should work OK, but that's a lot of clamps!

 

[bob58o]

Thinking about royal purple break in oil???
Going to use the 37 lbs springs because the pockets are cut for the bigger springs and I don't have retainers for the smaller ones. I guess I'll break it in all together? Cam, piston rings, valve train, ...
Not sure I can wait until I can apply a good load. Maybe I'll strap it on the buggy.

 

[bob58o]

Sweet 16.

 

[Kleyny]

Figured it out. I couldn't even push the slide up with my finger, so I assumed the spring wasn't in there correctly.

I took it apart and realized I had the white plastic piece that holds the cable (gets inserted into the slide) upside down. When correct, the spring fits around the lip on the top of the white piece. There is no lip on the other side so the spring just sat on top of it when that white piece was upside down. Also it seemed like the cable would pop out easily the other way. It seems like it is secured much better this way.

I am fairly confident that it is correct now.

I can't build a monster if if the carb only opens 75%.
Very happy now that it wasn't a junk carb, just a garbage builder.

That's better lol. One day I might put a slide carb on the gx. Need a rod and flywheel to come up cheap first lol. I'm already getting told I'm spending too much on it lol

---------- Post added at 08:37 PM ---------- Previous post was at 08:29 PM ----------

How bad is it to use an impact wrench to torque the flywheel wheel nut on? I haven't tried rope in the spark plug hole yet, but nothing else has made this task very easy. I've interlocked some wrenches and put them through the starter cup, but felt that was going to give. I tried ratchet straps , but the HF ones I had didn't work great.

I tried the rope in the chamber trick and it didn't work for me either, tried vice grips this also didn't work. So it was a impact wrench for mine. Hopefully nothing bad happens to it.

 

[KartFab]

AHHHHH i cant wait to see it running.

 

[bob58o]

Well I will start it up soon. I don't think I can wait til it gets strapped into the minibike I don't have yet. I know a lot of people like to break in the engine hard under normal operating load (Drive it like you stole it). Supposed to help the piston rings seat better. But a lot of people, including the manual for the engine, say to baby it for a while.

Since both seem to be accepted, I guess either should be ok.
Since I don't have a load to put on it, I will break it in with no load initially. First at idle (where ever it may idle... 2500? 3000?) for a bit, then a few hours of constantly changing RPMs and throttle opening.

I like this debate so feel free to input. This one gets heated. The "break it in how you will drive it" VS the "set the throttle with no load and walk away".

Any way, most people agree that RPMs should not stay constant. You should try to vary RPMs every coulple of minutes or so.

 

[bob58o]

Need a rod and flywheel to come up cheap first lol.

I'm guessing gx200???
This is cheap"ER"
Should be good for gx160, gx200, clones, (non-hemi Predators too I think)

PVL FLYWHEEL, CLONE, HONDA GX160/200
Item Number DC-PVL-FW
Price $64.95/EACH

DESCRIPTION
PVL is known for making quality flywheels. This flywheel is dynamically balanced and has been tested by PVL at 17,000RPM. The steel center hub adds durability to keep from damaging the taper. The center hub also has tapped holes for the use of a flywheel puller.
Approved by all major sanctioning bodies.

SPECS
Engine: 196cc OHV Clone, Honda GX160/200
Brand: PVL
Material: Die cast Aluminum
Weight: 3.8 lbs
Timing: 28 Degrees
Fins: 12

http://www.dynocams.com/item/dc-pvl-fw/

 

[Kleyny]

I'm guessing gx200???
This is cheap"ER"
Should be good for gx160, gx200, clones, (non-hemi Predators too I think)

PVL FLYWHEEL, CLONE, HONDA GX160/200
Item Number DC-PVL-FW
Price $64.95/EACH

DESCRIPTION
PVL is known for making quality flywheels. This flywheel is dynamically balanced and has been tested by PVL at 17,000RPM. The steel center hub adds durability to keep from damaging the taper. The center hub also has tapped holes for the use of a flywheel puller.
Approved by all major sanctioning bodies.

SPECS
Engine: 196cc OHV Clone, Honda GX160/200
Brand: PVL
Material: Die cast Aluminum
Weight: 3.8 lbs
Timing: 28 Degrees
Fins: 12

http://www.dynocams.com/item/dc-pvl-fw/

Cheap as chips if I was in the US the shipping to Australia is a killer. I just checked these guys shipping and they dont ship to Aus by the looks of it.
I'll find them one day, Rome wasnt built in a day

 

[bob58o]

Cheap as chips if I was in the US the shipping to Australia is a killer. I just checked these guys shipping and they dont ship to Aus by the looks of it.
I'll find them one day, Rome wasnt built in a day

Sorry I forgot and sometimes I don't remember to check location. Thanks for filling that out BTW

---------- Post added at 11:11 AM ---------- Previous post was at 10:28 AM ----------

http://www.dansgaragetalk.com/topic/364-nibbi-carburetor-dimensions-and-jetting-chart/

Going to put this link here so I don't loose it.
It gives a few different carb styles and sizes and gives stock jetting sizes for each.

For example...

PE 24 (38 idle / 112 main)
PWK 26 (38 idle / 110 main)
CVK 24 (38 idle / 108 main)

I think I'm going to start around 40 idle / 120 main.
Figure my open exhaust may need bigger than stock jetting, and maybe with out the power jet (which I will not be using) the main should be bigger. Anyway... I think I'll start with the needle raised up one position and a 40/120 jet combo. Rather start rich than lean. I'm not drilling this time, so I don't have to start the jets small and drill bigger. I can start big and just swap to a smaller jet from the kit.


I think the power jet is designed for two-strokes and seems to be problematic on 4-strokes.
KISS - one less thing.

https://www.youtube.com/watch?v=zKp9Z8vuOXc

 

[bob58o]

So I got some fresh 100 octane gas.
I got some Royal Purple Break In Oil.
I'm going to throw the 40/120 jets in the carb and install the stock flywheel at 32 degrees.

Going to slosh around some cheap-o oil and drain it to help clean up any garbage, then use about half a quart of this 10W-30 Break in Oil and try to fire it up. Not sure I have a place to mount this engine in this apartment.

I should be able to try to start it today or tomorrow.

 

[bob58o]

Rotated the recoil started.
Replaced Rota-Derp sticker with this one.
Isky sticker worth bout 0.7HP alone.
It's a perfect spot for a DIYGK sticker. I have none.

But since I have NOT a single Isky item on this build....
I will showcase the Isky sticker. (It's a cam lobe).

They sent stickers when I ordered my Robertson pipe from small engine cams. Kartpipes was down at the time of my order???

 

[bob58o]

Please send free stuff!

 

[bob58o]

I raised the needle (lowered the clip) 1 position. There are 5 positions. It was in the middle (3rd). Now it is in the 2nd from the bottom.
I installed a 40 idle jet and a 120 main.
I set the air screw to 1.5 turns out.

I checked to make sure all my nuts, bolts, screws, and hose clamps were tight.

I filled with oil. Sloshed it around. Pulled the started cord a few times. Drained the oil.
I filled it again, sloshed it around, pulled the starter cord like 15 times. Drained the oil.
Did it again, pulled the cord around 20 times, and drained the oil.

Next time I'm going to fill it with this Royal Purple Break In Oil and add some 100 octane fuel.
I only have 1 quart of the break in oil, so 1/2 for the first 30 minutes then an oil change.
And the 2nd Half for the next 3 hours and then another oil change.
Then I'll switch to what ever oil I'm going to be using.

Let me figure out where I can bolt this engine to break it in. Hopefully this afternoon.

http://www.jegs.com/i/Royal-Purple/...VX-9_WYTtfy9OMokWbcB3SI50svWmuAoaAg0fEALw_wcB

Royal Purple 11487
Break-In Oil 10W-30

Engine builders have grown increasingly concerned that many modern motor oils do not provide adequate wear protection for new engines, particularly those using flat-tappet cams. Royal Purple has addressed this issue by developing a new engine break-in oil that promotes a gentle start-up and gives you superior protection from rough-running engine problems.

Royal Purple combines highly refined mineral oil, preferred for engine break-in, with advanced additives containing high levels of zinc and phosphorus to optimize protection in flat-tappet and roller engines.

Royal Purple Break-in Oil is formulated to allow optimal ring seal and protect rotating assembly components such as the camshaft and valve train from initial start-up wear. Its high film strength provides engine protection superior to full synthetic oils that are not engineered specifically for new engines. Perfect for your new factory-ordered vehicle and engine rebuilds, Royal Purple Break-In Oil is fully formulated and does not require the use of any other chemical additives. After the engine is broken in, we recommend using the right Royal Purple high performance synthetic engine oil for your vehicle.
https://www.youtube.com/watch?v=K1nBGzotYgw

 

[Kleyny]

Have you decided on a break in procedure yet?

 

[ezcome-ezgo]

ooo I am sooo excited.

 

[Whitetrashrocker]

Your redundancy is killing me.
They rebuild top fuel engines in less than an hour.
You spent half a day sloshing oil.
Come on. It's a lawnmower engine. They run on Maple syrup and beer.