Evolution 46NX Head Shims

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airplanescotty
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Evolution 46NX Head Shims

Postby airplanescotty » Sun Nov 20, 2016 8:51 am

Right after Hodges race I went to Horizon to buy some Head Shims :P :P , found the Evolution 46NX Head Shims however they on backorder till Late November,,, which is now!

Today I looked in the Evolution Head Shim department and nothing listed for the 46 NX????? I also looked to see if the 40 or 52 shims are comparable and they are not!

Am I looking in the wrong place??? Is there an alternative?? Does anyone know the proper part number?

Appreciate the Help :) :) :P :P

Scotty
QTR Racing


cbk07
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Re: Evolution 46NX Head Shims

Postby cbk07 » Sun Nov 20, 2016 10:41 am

Scott, the part number is EVO100112. I have an extra package of 2 shims. If you need them, PM me your address. Craig


pastpres
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Re: Evolution 46NX Head Shims

Postby pastpres » Thu Nov 24, 2016 10:04 am

Scott, if you are blowing plugs, I have successfully used a K/B short with one washer. The exact mph was seen with this plug versus a K/B long with an additional .008 head shims added. Lloyd


Bob_T
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Re: Evolution 46NX Head Shims

Postby Bob_T » Thu Jan 26, 2017 1:03 pm

I know this is a couple of months old, but ... I could not find any head button shims available to purchase, other than the ones from Horizon, which are .004" thick, so I made my own .002" shims from brass shim stock. I bought an exacto blade style circle cutter, measured the existing head button shim, and then cut my own. The Evolution shim "kit" has two 0.004" shims in it. For the same price you can buy their engine gasket kit which has the same two shims and a backplate gasket. Both our 46NX engines had 0.008" shim in them from the factory. One had one 0.008" shim, the other had two 0.004" shims in it. One engine has about 15 heat races and a couple of practice runs on it and then it started blowing glow plugs. I didn't want to add another .004" shim, so I made my own .002" shims. Have not had a chance to run it to see if that helped. The other engine just has bunch of break-in runs on it with the 0.008" shim, and has not blown a glow plug yet.

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airplanescotty
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Re: Evolution 46NX Head Shims

Postby airplanescotty » Mon Jul 03, 2017 10:16 am

My EVO's have little needle response!!!!

I am in Florida, hot & Humid :o ,, have three shims under the head , have tried K&B & Merlin Red & Green's, as I squeeze the needle,, it transitions from rich to the pipe! Further turning of the Needle results in no increase on the tach!!!

I launch just at the point of transition/lean and the plug comes out dark,, not real back but darker than I think it should be!!

I am getting ready to add and subtract shims to see if I do in fact get an adjustable Needle range :lol:

Has anyone experienced this and know of "THE" solution???

As always,, Help is SOOOO Appreciated :) :) :P :D :roll: :roll:

Scotty
QTR Racing

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airplanescotty
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Re: Evolution 46NX Head Shims

Postby airplanescotty » Mon Jul 03, 2017 2:36 pm

Well,,,, I did some Tinkering and here's what happened :lol: :roll:

I removed one 0.003 head Shim and Needle Valve adjustment, from "On The Pipe" to Peak,, magically appeared or re-appeared :P ,,,, so being from the Great US of A, More is always better :D I removed the second Head Shim, leaving one shim and Needle Valve adjustment once again joined the "Dearly Departed"

Clearly Not a Perfect World!!!!

SO went back to Two Head Shims, as shipped from China, and will see how it reacts in Indiana ~ Oh Boy :P :P :roll:

XXOO

Scotty
QTR Racing

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airplanescotty
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Re: Evolution 46NX Head Shims

Postby airplanescotty » Mon Jul 03, 2017 5:09 pm

When changing Shims for the first time on my EVO, I noticed the Head Bolts/Screws were really SNUG, took force to loosen!!!!

So, on my Newest EVO,, I used my inch pound torque wrench/Screw Driver Handle to UNscrew the Factory Stock head screws to try to determine how tight China set them!

I started at a setting of 12 ~ just clicked. Then to 14 ~ another Click, Finally at 16,,, the Screw began to unscrew :D :) :P :o :roll:

I used to set them at 14!

Scotty
QTR Racing


Bob_T
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Re: Evolution 46NX Head Shims

Postby Bob_T » Thu Jul 06, 2017 8:45 am

I have found their "torque" to be very inconsistent. On 4 brand new engines, some of the head bolts were really tight, and others were barely beyond finger tight, sometimes on the same engine. Last year at Muncie, we started blowing glow plugs about half way through the day (OS #8). Tried a couple of other brands/lengths and still kept blowing plugs. Added another shim and it quit blowing plugs.

Another thing to check on those engines ... since they don't have pin for the notch in the sleeve, the ports are not necessarily aligned with the ports in the crankcase, as received. I always take the head off, and with the muffler off, look through the exhaust ports to get the transfer ports aligned as best as possible with the ports in the crankcase casting. Having the exhaust ports "centered" in the crankcase casting exhaust port does not align the transfer ports very well .

Just a couple of things I have learned/observed. :)

Bob


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Re: Evolution 46NX Head Shims

Postby DonStegall » Sun Jul 23, 2017 4:33 pm

I will be getting shims for the Evolution .46NX made in .001", .002", and .005" (Maybe .004" as well) sometime over the next few months.

For those who do no know, I was in the hospital from 7/10 through 7/13 with kidney failure and heart irregularities. I had a Remicade infusion on 7/14, so basically I was in the hospital for a week.

I have not been feeling well since the first part of April and it really slowed me down.

I'm still getting winded with minimal exertion, so I'm going to the cardiologist as soon as I can get in. Hopefully tomorrow. They had said that a heart cath would be a good idea, but my kidneys had to recover first because of the contrast they use during the cath is hard on the kidneys.

I plan to be posting a lot now. But if I go MIA, you'll know why.


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