Hemi Predator Build #2

[bob58o]

Piston, crank, connecting rod, camshaft installed...
Piston tool didn't get the top ring. I manually compressed it with my finger nails and finished installing that way.
Rod bolts lubed and torqued, again.
Crank shaft and camshaft markings aligned.
Let's see if I can measure lobe to cylinder clearance, then I'll put the side cover on and see if I'm 0.005" in the hole like I expect.

 

[bob58o]

With the side cover on and a few bolts hand tightened to hold the side cover on, I measured between 0.005" and 0.007" with the feeler gauge so I'm ok calling my piston 0.006" in the hole.

I think I may need to clearance the bottom part of the cylinder. My permanent marker on the lobe seems like it got rubbed off. Going to have to uninstall the con rod to measure the clearance and grind away if needed.

 

[bob58o]

Without the side cover, which will probably make it tighter. 0.018" intake lobe clearance. Lifting the end of the cam (to simulate support from the side cover), I got about 0.010" clearance.

Going to try to remove 0.025-0.035" from the bottom of the cylinder in the two locations for the two lobes.

 

[bob58o]

Should be able to grind away enough and stil have plenty of cylinder wall.

 

[Whitetrashrocker]

Nice clear pics there Bob O.

Don't they warn of block clearancing for that cam anyways?

Looking good!

 

[bob58o]

Nice clear pics there Bob O.

Don't they warn of block clearancing for that cam anyways?

Looking good!

They do. They said "Honda" blocks need clearancing. I wasn't sure if it was just Honda or clones and Predators as well. Any way it is done. I'm sure I took off more than needed.

 

[bob58o]

How I feel when I wash parts with gas.
https://www.youtube.com/watch?v=aWeG6Ea84zg

---------- Post added at 01:37 AM ---------- Previous post was at 01:33 AM ----------

Next I want to see if I can get it put back together with the lifters and pushrods and check for coil bind. That video from Jody at ARC said you can get .300 lift out of the 26lb spring on the intake. A little less on the exhaust. I think the exhaust valve is a little shorter.

 

[bob58o]

Stock Valves and Retainers. 26lb springs. No shims.
Installed height= 0.875"
Not sure what it is supposed to be, but I'll put the head on and check for coil bind.

 

[bob58o]

I checked for coil bind. Seems fine. Probably around 0.050" - 0.060" between the coils at max lift. Its not easy to measure with the feeler gauges. I'll have to remove one of the rockers, measure the other spring, then switch.

Picture is Exhaust valve. Zero lash. Max lift.

The box the cam came in says 0.002" lash for the intake and 0.003" for the exhaust. Also says to break in the cam by running the motor on a stand at 2000 RPM for 20 minutes with no load using the stock 10.8 lb springs.

 

[KartFab]

I checked for coil bind. Seems fine. Probably around 0.050" - 0.060" between the coils at max lift. Its not easy to measure with the feeler gauges. I'll have to remove one of the rockers, measure the other spring, then switch.

Picture is Exhaust valve. Zero lash. Max lift.

The box the cam came in says 0.002" lash for the intake and 0.003" for the exhaust. Also says to break in the cam by running the motor on a stand at 2000 RPM for 20 minutes with no load using the stock 10.8 lb springs.

sounds like the same instructions i got form NR racing

I have had pretty good luck with that zddp containing royal purple break in oil, then switching to the royal purple HPS to protect the cam lobes and still get the benefits of synthetic. Also have the oil drain plug with a magnet in it to keep some of the steel junk out of the oil.

 

[bob58o]

Calling Functional Artist!!!
I need help with my Bowl work! Lol

I guess it's starting to look more like something?

Well if this head gets destroyed, it was a learning process and I could always get the NR head.

 

[bob58o]

Pretty sure this is the stud kit I used for the side cover on the last one.
https://shop.advanceautoparts.com/p...0KAHoUARgfG3_XssSFQaAr6tEALw_wcB&gclsrc=aw.ds

7 bucks 10 studs. A bit long when using the 30 series backplate, but $7 is cheap.

I wish my welding was better. I want to make me some of these reinforced Hemi rockers.
http://www.ebay.ca/itm/PREDATOR-212...STOCK-ROCKER-ARM-HIGH-STRENGTH-/272740378666?
Seems a bit high priced, but not many alternatives. Somebody make me some for cheaper???

 

[ezcome-ezgo]

Go billet or go home.

 

[Scout]

I might have missed it, but which cam are you using?

 

[bob58o]

I might have missed it, but which cam are you using?

I changed my mind a few times. wanted the 285 series, then the Isky Black Mamba Jr, then the 285 again.

NR Racing 285-0211
285 means 0.285" Lift
02 means 102 Intake Center Line
11 means 111 LSA

"Serious mid-range camshaft for serious motors. Lobe designed esp. for Honda GX series Motors .

Approx .285 lift and 250 duration (at .050). Cam allows use of stock valves with 1.2 rocker arms when using our springs. This cams likes big carbs and big ports. Will easily make 20 hp when used with correct combination. Best with 24 mm Mikuni, big valves, and high compression. Honda blocks must be clearanced to install.

Camshaft, 285-0211: 7000 RPM. 11.0 to 1 compression or more. 26+ lb Springs Required, Small track cam for serious torque"

According to Russel at NR, it should pull from 4k to 7.5k. Gearing (7k RPM = 60mph) or my 26lb valve springs should limit my rev's to just north of 7000. Going to use a TC with Driver Springs and Weights for a 4k RPM engagement.


http://www.nrracing.com/product-p/200cam-285.htm

 

[ezcome-ezgo]

Glad you're not taking this too seriously.

 

[bob58o]

Go billet or go home.

I have a billet connecting rod. That is all. I will go home. No billet flywheel, no billet rocker arms, no billet side cover, no billet gas tank...

Need to get me some billet tires to go on the billet wheels. Going to order a billet helmet to protect my billet head.

---------- Post added at 09:19 AM ---------- Previous post was at 09:15 AM ----------

Glad you're not taking this too seriously.

Karting is a very serious matter.... So lets put a smile on that face.
https://www.youtube.com/watch?v=F_5dP_83O7o

 

[ezcome-ezgo]

Your dedication to billet is admirable. I shall incorporate billet into the word game.

 

[bob58o]

Well I ordered the NR head...

Items Ordered: Price: Status:
1 of : Head, Racing, Hemi for 212 Predators and 6.5 Chinese OHV's[Valve & Spring Combination (Heads):HEMI 28mm Intake, 25mm Exhaust (+.070"), 37 lb Springs, Aluminum Retainers][Milling Options:Other (please email with spec)][Rocker Arms:OEM (stock ) Rocker Arms 1 to 1]
$209.99 Processing
2 of : Keepers, pair, 5.5mm, Middle Groove

1 of : Lash caps, 5.5 mm, Hardened for Stainless Valves (GX200 & 6.5 Chinese OHV's), Pair

2 of : Retainer, 5.5 mm (GX200, 6.5 OHV), Aluminum, 37lb Springs, each

2 of : Shim, Valve Spring, Small (GX200) .015

1 of : Springs, Valve, 37 lb., Red Stripe (Improved), Pair

1 of : Valve, 25 mm x 5.5, Stainless, +2.58" Long (+.070")

1 of : Valve, 28.5 mm x 5.5, Stainless, 2.58" Long (+.070")

 

[bob58o]

When replacing the intake studs with bolts when for an intake adapter, what size bolts do I use?

Anybody know what the bolt size and thread pitch are for the holes in the head where the studs were attached?

I can figure it out but don't have the head or the studs with me now.