Vlad's rides thread

[vlad01]

Mind you, those are 2 totally different gaskets. on the engine is genuine GM, on the intake is nasty cheap payne gasket. And yes the shadow at that angle makes it look different.

I measured the ports with verniers and locked them and it was pretty bang on for the lower part of the manifold port.

[Holden202T]

at the end of the day, is the manifold is smaller or the same as the gasket its not going to hurt much, the real killer is if there is a step from the gasket to the head!

[vlad01]

the gasket is bigger than both, both manifold and head are pretty bang on.

So cross section view of one wall is like this.


intake ----------_---------- head


I know ideally everything should be blended to be a continuous wall but that would mean enlarging my ports quite a lot just to get to the gasket. That will reduce velocity and go against what I'm trying to achieve.

I have thought about milling inserts that fill the gap in the intake port. But I wont bother with this build, I dont think it will benefit much for the trouble.

[Holden202T]

at the end of the day, anytime spent making everything match even the smallest bit is going to be an improvement over stock

[vlad01]

My biggest improvement in matching was simply by moving the manifold as far forward as possible using just the play in the holes (a fair amount of play in fact).

When centered, the manifold is misaligned by about 2mm.

The only thing i have found an iphone useful for is port matching lol.

[VK_3800]

I wouldn't worry about the gasket being larger, just get the manifold and head aligned as best possible. Assume that air will be "trapped" in the gap created by the larger gasket, effectively filling out the walls and making it smooth for the flowing air again, which is fine. Whereas a sideways step or a reduction in area if the head and manifold don't match will cause the flow to be diverted or disrupted, which is no good.

[vlad01]

And that's exactly what my goal was, and it was achieved.

[vlad01]

So my order is being sorted.

Only the ecotec timing covers are obsolete by the usual part number and the CAS shields are obsolete for the pre eco despite being listed as stocked.

Good news is there is a new part that supersedes the old cover and is goes by the # 19332914. This is now a separate order as there is some time to back order it, also chucked in 2 doughnut style knock sensors for 22 each. Going to plug the factory knock sensor thread as its the oil gallery and remove it entirely from the harness. Pretty useless system on the 808 really. Knock ears are the way to go.

http://www.newgmparts.com/oe-gm/55353316

This stuff might not arrive when I will be home. Going interstate for a total of 3 weeks before work closes up. So might be my x-mas project to get the rest of the long block finished

[vlad01]

The other little bits are on their way with DHL, should arrive next week so hopefully before the weekend!

I'll be finally be able to finish the timing cover and get that all mounted on.

[vlad01]

Matched the elbow, it was out tons. about 3mm on the drivers side.

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a comparison, not a great pic but in real life its easy to see how much larger it is vs stock. Its quite deceiving as you keep focusing on the trimmed areas inside the ellbow and not the actual gasket face.

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Great match! even reduced the bump at the bottom and removed a rather larger casting boss up top.

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