Vapor Blasting

[528i-1981]

Gents: Brought a replacement valve cover (hat tip PatinaBeforePolish) and six 320is valve runners to New England Blastworx in Hinsdale NH for vapor blasting.





10 micron glass beads and water at high pressure. The result is a creamy smooth surface with the pores in the metal peened closed so that they can be wiped clean. Still waiting for the frame welding to be done before I can mount these ...

[maybeillbuyit]

Looks amazing Eric. I am looking for two more 320i intakes to have enough to do that modification as well. What did the glass beading cost?

[528i-1981]

All six tubes plus the VC for $150.

Yes, I can't find any flaws except one small stain where oil had leaked through one of the intake runners from the inside. These parts look better than new. Turnaround was under a week.

[Lock]

Agreed that looks great, I was thinking about painting some of my old parts but getting them as clean as that is a better result.

[528i-1981]

Here are the E21 runners mounted.



The fuel rail was painted with Master Series urethane-based coating. The color is a close match to the vapor-blasted aluminum. There is a black topcoat available as well, which I've moved to from POR-15 everywhere on my E12.

[keehn]

Eric,

All I can say is WOW!! That's a fantastic job the vapor blasting did to your parts.

Makes me a bit jealous, since all I'm doing is dry glass blasting. Mine may be clean in the end, but I doubt it will have your finish.

Mike

[528i-1981]

Thanks Mike, very kind words. Here's the accumulator and thermostat housing in place.

[528i-1981]

And it's a wrap ...



She started right up and drives well. Need to attend to a small coolant leak somewhere and adjust the idle. The E21 runners do make for a noticeable change in the torque curve and the engine notes may be somewhat different, but it's running now without the hood on so I cant's say for sure. The only other change was to the spin-on fan from the bolt-on. My car was built in 4/81 but had the old-style bolt-on fan - perhaps the factory was liquidating parts at the end of the production run? That alone is a huge upgrade.

Again thanks to Jon (patinabeforepolish) and Lach (lock) for selling me needed stuff over the past 12 months.

[keehn]

Eric,

Fantastic job on your E12! It looks great

One tip: Verify that your vacuum advance actually WORKS. I decided to test mine (sucked on hose to create vacuum) and it did not. The new vacuum advance from Germany does move under "mouth" vacuum, proving to me that there was indeed, a problem with my original unit. When you suck on the vacuum inlet, the metal "arm" on the other side should move inwards as the diaphragm moves.

While timing does not call for vacuum advance, a broken vacuum advance WILL impact performance while driving.

Mike

[Lock]

That looks great Eric, the engine is now as shiny as your aluminum radiator.

And the spin-on fan is a worthwhile upgrade hey. No more draining and removing the radiator just to remove the fan to get access to the front.