Tag: aluminium oxide

Guesstimates about compression ratio 3 + oxidation stuff

Posted onLeave a comment

Before taking the cylinder head for oxidation removal, I tried (my best) to measure the head volume.

Better get some proper measuring equipment. My trusty 10cc syringe wasnt that accurate, but I got a result that was definetly over 36cc’s. I’m going to use 37cc’s until I get better tools. Next time I’ll use windscreen washer fluid or some cheap alcohol, because surface tension.

My syringe actually stopped at 38cc’s 🙂

Then measured both the deck height and stock 4A-GZE piston compression height. Deck height is 191mm and stock piston compression height 30.5mm.

Valve guides are oxided as well. Or rusted. While getting degreased for the high-tech coatings, some of the alkaline washing liquid leaked inside and made a mess.

Compression calculations:

Seems that the stock pistons are level with the deck when at TDC. Stock 4A-GZE pistons have 30.5mm compression height and Wisecos have 30.68mm. Therefore Wisecos will poke 0.18mm above deck level.

  • Bore: 81.5mm
  • Stroke: 77mm
  • HG thickness: 1mm
  • HG bore: 82mm
  • Deck clearance: -0.18mm
  • Piston volume: 5.9cc
  • Combustion chamber: 37cc

With these values the CR is 12.3:1

  • 1mm headgasket – 12.3:1 CR
  • 1.2mm headgasket – 12:1 CR
  • 1.4mm headgasket – 11.7:1 CR
  • 1.6mm headgasket – 11.4:1 CR
  • 1.8mm headgasket – 11.1:1 CR
  • 2mm headgasket – 10.8:1 CR

Well, the numbers are the same as before… and squish clearance sucks when head gasket is thicker than 1mm.

Wiseco, you suck.

Aluminium oxide inside oil passages

Posted onLeave a comment

That white, powdery stuff there is aluminium oxide. And it’s baaaaad.

While being washed for those technical coatings, something happened and insides of the cylinderheads got exposed to washing agent. Aluminium reacted with washing agent and end result was aluminium oxide.

Aluminium oxide is that same stuff that is glued to paper to make sandpaper. Wonder what it would do inside my engine if left there…?

Nah, I’m taking it back to the coating company 🙂

Parts from coating

Posted onLeave a comment

Got some parts back from coating!

Cylinder head has some white crud all over it. No idea what it is and how to get it off.

Valves and everything (I mean everything, even the plugs) were coated in heat resistant stuff. Outside, cylinder head got a coat of stuff that helps heat to radiate away from it.

This is a Ferrari F360 flywheel if I remember correctly. Widric found it from our stash. 🙂

Pistons got three different coatings on them. Top of the piston was coated with heat resistant, skirts with friction stuff and the underside with that same stuff as cylinder head that will radiate heat away.

Some bits are now sandblasted and powdercoated. I will have to find some nice paint(s) to do the letters.

Not pictured here are the new camshafts, all the bearings and the block. Camshafts and bearings got a coat of that friction reducing stuff, while the cylinders were rubber with tungsten powder to… well.. reduce friction 🙂

I will get my exhaust manifold and turbo coated as well.