Interlan Engine work - fixing bad casting - port/polish

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So as you saw in part one, casting flare on the head is horrible and needs to be fixed:


Before:
After:


I did this thru the entire head interior. No more flare from casting anywhere to be found.


Now, I have this dremel in my hand, the head already needs to be cleaned professionally and looking at the intake ports, they are sharp, unequal and generally look like shit.
So, might just take the corners off a bit, and make it round...




that was simple enough... Looking inside the ports, oh god, I can't do any worst. it's impossible... how long can it take anyways right ?
this is what your intake looks like right now:


After 3 hours of work, this is how ONE of my ports look like:


its far from perfect, but its 100x better that it was. I left the hole where the injectors go as it was, I have read everywhere that it prevents fuel from pudling up this way. Ok.
now, I have 3 other ports to do, and they have to be very similar...


After 18 some hours, we have fully polished intake ports:



Now, looking at the exhaust ports, I know that not much power to be gained from polishing these. The ports are much smaller than the intake, so it's going to be even harder because my bigger flapping wheel doesn't fit in there, so, let's leave it alone...


GOD DAMN OCD:
another 20 hours later, this is what we got:


NOW we are done... hmmm, not really.


Looking at the combustion chambers, I notice that there are a lot of bumps and pores there, the side of the "circle" is razor sharp and even has some casting errors here and there that show as sharp protrusions on the sides, so again with the dremel, and sanding paper this time, we don't want to score a valve seat...


So I removed the sharp edges from the outer parts of the chamber. this is because sharp corners become very hot and can cause detonation if fuel hits the edge. We don't want this.
If you zoom in a bit, you will see that the metal is like swiss cheese, very porous. no I evened it out as best I could, but trying not to remove any surface area, we don't want to touch our compression ratio. Notice on the sides you can clearly see the multiple places where metal was taken off to that the circle is smooth to the touch. also sanded a bit of the edge of the circle to remove the sharpness. Not going nuts, just a touch of 800 grit to chamfer the edge off:


I then redid the seats for the exhaust valves, the contact area on the valve had very much variation from one to the next, and the exhaust valve needs good contact area so that it can dissipate the heat it deals with faster. more contact, more heat dissipation. Intake valve don't need it, they don't get as much heat to deal with being cooled by intake air, so I leave them alone, my engine was sealing perfect before I tore it appart, so I am not touching it.


That's it for this part of the work. Now the head needs to be cleaned at a shop, I will (I think) be reusing the same valves, but changing the springs to something stiffer. I will update once I get to this part.

Vi Engineered Turbo (V-Mount)
Forged LE9
DDM Works Fuel Rail
RRR Oil Catchcan
UPLOK + UPGUARD
Assault Hub / Steering wheel
DDM Works short shifter
PRP Shifter Boot
Cipher Race Seats and 4 point harness
XO Luxury Verona 20x12 Toyo R888 315/35r20, 19x9.5 Toyo R888 265/35R19
and more...

Comments 3

  • WoW, really awesome work

  • BTW, at this point I am around 60 hours into this, not counting all the reading I do before touching anything.