FOD PROJECT PISTON SLAP + BLOW BY BE GONE + 1 = 4 & THICK RING FUN EXPERIMENT!

   #41  

Jack@European_Parts

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Follow up tear down and cleaning..........lite hone and decks von 3M cookie.



Cross hatches fast .......good good Ja ja....



Lower deck cookie time......ja



cookie good enough now time to get tanked.......



Dress for pause to retain measurements stop corrosion.....bla bla

Time to start custom bore, offsets....stroke shaving rod length... plus ring gaps on fly because nothing in here will belong going forward in this carcass coming back from the dead.

 
   #42  

Jack@European_Parts

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Before I do anymore cleaning I'm taking some measurements & comparing data to surmise what I'm going to shave, sleeve or add....

As can be seen with the 2.0 crank, the crank hits the skirts and makes way to show lower oil ring.

This would be unacceptable.






Deck is also not ideal at current settings and unacceptable for 2.0 crank + rod.




A 1.8T crank also again reveals too much above deck as can be seen below.






Clearance of the skirt to crank is possible on 1.8T crank as can be seen below still issue for lower oil ring.



Piston compare of 2.0 to donor to be mangled to fit for perspective.







It is my opinion that the short skirts of the pistons may be better for high rpm and weight reduction, however, they are not useful in an RPM that would aid useful life or power to create clarity of combustion and are short lived, history also shows us this.

What I clearly see is skirt slap and rings wearing on an angle due to chatter resonance from piston not being held in bore consistent, they are susceptible to carbon and pitting as a result hence blow by!

Talk about planned obsolesce..... :rolleyes:

The rings are indeed with carbon, pitting and pistons with skirt slap burns.

It is with these small surface area contacts, the rings in contact with bore, fail to seal proper and permit oil into combustion process or fuel and gasses into the sump.

Considering a turbo motor will just blow the gasses into the sump, I see a huge advantage here in weight follow through inertia and the seal of the chamber even if I deleted the lower ring.

Now I may have to grind the skirt of this piston or add a sleeve to block and this is all entirely possible.

Considering other custom settings and hardware in my thoughts with junk.

It's more fun to use stuff already in production and mod it or cross it to do what you want and sure is cheaper.
 
   #43  

Jack@European_Parts

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Sleeve idea nixed due to oil gallery too close to bore.

I think this is quick and dirty for bypass of oil sprayers.

Yeah more engine porn .....








So guys are going to be like WTF Jack, why are you doing that, sure sounds contradictory?

Here is the thing....... oil is friction and so are hydro-static pressures.

Too much oil pressure will grab a crank or rod and stop it from turning or alter valve timing for lash changes in lifters or certain vario conditions and temps can soar as a result.

Understanding hydro-statics is important and as a farm boy I understand them well with all the heavy equipment built or maintained in life.

Oil sprayers or even in conjunction with rifle bore on a rod to connecting rod to crank is way dumb for anything performance in mind and in tests I have done violate the spirit of useful life or function as stated.

The original spirit of the sprayers was to reduce temps of the pistons related to mid evil knock control systems and SMOG related in addition to lubrication of pin and bore well allegedly! :p

While in original spirit or intent this maybe noble on paper in some SAE publication, however, I can tell you it is wrong and my by own verification why motors explode at track or under extreme endurance when pushed!

When you lose oil PSI at crank mains or rods and or oil sprayers, especially under certain conditions you lose big time in head area and those are even more critical friction components you just dont play games with.

Because the blocks are for most part cast iron and the heads aluminium they expand at different rates.

As you can see the OEM's put tremendous friction requirements on valve trains now & with variable cam, lift timing or the HPP and fail to adapt around existing issues by missing their own basics.

Fact when removing oil being sprayed in rod or pop off sprayers, you lower temps under normal and race driving conditions due to added needed oil getting to valve train under conditions under constant load ( cruising speeds ) or increasing load offsets.

Guys would add external oil coolers it was such a problem in the early engines because an MFA would reflect temps in the 300 range on a hot day under normal driving WTF!

Deleting the sprayer's cut temps literally in half and GHG at tailpipe were far better believe it or not.....

I cap them off ......... A sprayer can stick open from contaminated oil, sludge and ethanol content fuels that forces them to be stuck open!

If the sprayer jets ball sticks open, it's not a good time for the engine since in main oil gallery, especially the cylinder head!

Getting the harmonious oil PSI in all ranges with adequate volume are key to reducing friction, aeration and lowering GHG's.

Too much oil sump level or spraying around only assists with a failure of cross contamination and temperature increases.


Let's dissect a sprayer......

 
   #44  

Jack@European_Parts

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I'm curious if a late 1.4T crank would suffice to assist fitments and mod fun further with reluctor adaptation or update to other rear seal cover?

Hmmmmm thinking out loud!
 
   #45  

Jack@European_Parts

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Diff rods indeed permit a different rock point of 2.5 MM

Believe it or not the center of that dome piston is above deck by .75MM






Yeah things would be extremely tight on bottom end too and that lower ring will get NIX'd

Still de-stroked ......

Could in theory still take advantage of larger ring sealing surfaces and extended skirt length for inertia to prevent resonance slap.


 
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   #46  

HMC

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Hi Jack,
I am slightly confused where you have got to at the moment. Looking at the last image, is a longer rod and a shorter stroke crankshaft a possibility to keep the bottom ring lands in the cylinder and reduce the piston projection from the deck? What about easing the piston skirt where you have the crank webs fouling, so you have a slight slipper piston effect but the thrust faces are the same length, which is I think what you consider important?
Regards HMC
 
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Jack@European_Parts

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That's the plan indeed.
I am in process of getting another crank with even shorter stroke and going longer rod, that was where I left off waiting for parts from freight still held up.

I want to see what a 1.4 will reveal at 80 and maybe try 140mm rods vs current 136mm

Than maybe utilize the rear end seal reluctor for G28
 
   #52  

Jack@European_Parts

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Final fantasy mod config piston clears.........




Deburr by hand little at time refit till right!

Establish between crank weights.....




Lots of shave free hand hillbilly style ........ Miss my Uncle and down draft table + a lunch....... :cry:





Clearance's achieved for both rock points......and looks like a GREEN light.....





 
   #53  

Jack@European_Parts

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Now that is tight and that is at taper point!




Bevel control secondary compression ring at taper point.




OIL control ring at taper.




Perspective compare of stock to larger ring.




Just look at reach difference to piston from ring depth to retain oil to seal better ....

STOCK IS ON RIGHT SIDE ZYL #2




NOSTRAJACKASS COMMANDS FORCE OVER TIME TESTS COMMENCE SEAL INTEGRITY, TEST INSTALL .......NOW!


 
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   #54  

Jack@European_Parts

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I am extremely happy with how this piston design holds for leak down overnight!
:popcorn:

I'm thinking AMU configuration for this block!

PD oil sump.....
 
   #56  

Jack@European_Parts

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Other 3 rods finalized.......

Reamed and Polished on garbage can for hillbilly roots...




ZYL # 2 piston in the rough cut compare.



Bottom perspective ZYL # 2 rough cut hand ground by eye & memory from ZYL #1 custom fit perspective.




 
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Fred's Imports

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You're going to coat those piston skirts right?

Been doing my own pistons for about 10 years with Calico CT-3 sprayed on then baked in mama's oven. Have a few VW, Chevy LS and BMWs running around with it, no problems whatsoever.
 
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