Exhaust Manifold Porting

Not much to say here. I did a home porting job during my engine rebuild, worked on the stock TD05/14B, 95 exhaust manifold, and 95 O2 housing. Later I ported the turbine side of my new 20G, and gasket-matched the 95 exhuast manifold runners and the head's exhaust ports. Porting seemed to help the spoolup a LOT on the stock TD05 turbo. NOTE: do NOT try this at home unless you have a heavy-duty air or electric die grinder and carbide bits. It will take HOURS as is. If you try this with a Dremel, you'll be lucky to finish it in days or weeks.

Click on a pic to see the fullsize version.

	The stock exhaust manifold exit to the turbo - note the infamous "step" for the ring gasket. As noted in the turbo porting VFAQ, toss the ring gasket, and grind this step TOTALLY away in the exhaust manifold.
	The step is gone! Took about 1/2 - 1 hour, and thankfully I had a thin-tipped bit, as otherwise it would have been a TOTAL pain near the center divider.
	Marking the head flange for gasket-matching. I just used a marker, but am going to find some Dykem (machinist's dye) for the next porting job. UPDATE: Port to match the stock 1G composite gasket, NOT the new stainless one. Porting out to the stainless one is largely a waste of time, as you can't port the runners that large, and if you port the head to match the SS gasket also, you'll have a dead spot in the airflow due to the head flaring out, then the exhman flaring back in. If you don't have the stock composite gasket, it is less than 1/8" larger than the openings in the exhman runners, so you barely need to open it up. When I port them now, I only clean up any protrusions in the entrance, and leave it at that.
	Most of the rough grinding done. Note I packed the runners with paper towels to keep the metal bits up front for easier cleanup.
	Closeup of grinding. Note that I haven't finished the one on the far right - you can still see the scribe line. You can see WHY I used paper towels at this point. NO! Porting isn't messy!
	Finished grinding - see how I didn't go in too far, only a little over an inch.
	Closeup of a runner.
	Convenience mod - I smoothed all the rough seams on the outside while I was at it, just to make it easier to handle over its' life. Only took a couple of minutes, and made it look better.
	Grinding the driver's side corner. This is necessary in order to fit in on a 1G, as without grinding it hits the engine mount.
	A closeup of the tight fit between the exhaust manifold and engine mount - THIS is why you need to grind the corner. I drilled and tapped the outer 2 holes in the head for 10mm studs like the 2G heads, but it is not TOTALLY necessary - many people have just used the stock 8mm studs just fine.

SO, that's it for porting.

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