Most liked posts in thread: SuperTurbo Mini Project

It's a bit difficult to measure at the exact point-of-failure. My best guess is at least 400 degrees continuously and close to 1000 degrees momentarily.

Just to repeat: I get these spikes because the header+turbo flange sits less than 2" away from the valve cover at the closest point! A normal cover shouldn't see anywhere near these temps.

 

I definitely agree that machining or fabricating internal baffles would be difficult . It's possible to cast them, but my spider sense sais that it would take several tries to get it right.

The external solution is trivial to implement, cheap, and 100% reliable. You can buy PCV valves in a baffled container off-the-shelf. All it needs is a hole about 1.25" dia. in the cover.

 

Wohoo! over 5,000 thread views!!

Ok maybe it's not a big deal for you guys, but it's the most viewed thread I've every had....

 

Been really busy at work & haven't had time to give updates...I'll try to put something together this week.

In the mean time, here's a couple of pictures of my modification to the turbo downpipe to merge in the wastegate bypass smoothly back into the exhaust. I TIG welded the merge pipe on myself, and I cut off & welded on a new exhaust flange...it was a good excuse to learn how to weld. Next winter I have a goal to build a new downpipe with a better design all myself....but I'll need to practice a *lot* before that!!





BTW, I've been cleaning out & organizing the garage to give myself a good metal workshop space. I still have to get a few things, but I'm making good progress (sorry they're a bit blurry):





When I'm done I plan on posting some info on what/how I set it up...

 

Yeah, I've heard of that technique, but I haven't tried it yet. I assume you tap off of the argon tank for the feed. Where do you find rubber stoppers that big??

Another person suggested fitting an aluminum tube inside that fits fairly snugly. It won't fuse to the weld & keeps the inside nice & smooth...

I really should have taken pictures of the garage beforehand. I've thrown away a *lot* of junk to get it to this state.

 

Thermal testing

I realize that people are waiting on an update on my Aluminum valve cover. Unfortunately the local shop I'm working with has been backed up with "real" work with Oil firms & gov't projects, so it's take a bit longer than anticipated...

In the mean time, even with the new Aluminum cover I still need to protect the back of it to reduce the heat transfer to the engine. I purchased some high-tech heat reflection foil that is supposed to reflect 96% of the radiant heat:



But given the fact that the last protective material I put on the cover vaporized in a matter of minutes, I decided to first do a semi-quasi-scientific study on heat transfer to the cover with and without protection.

For reference, the melting on the cover from the Turbo looks like this:



To recreate the indirect heat of the turbo, I set up a propane torch approximately 1.5" from the cover. I placed a sheet of thin steel between them to convert the direct flame into a radiant source:



I used an IR temp sensor capable of measuring up to 1400F to measure various points. With a moderate flame I was able to produce a radiant spot about the size of a quarter.



This in turn heated the cover to about 300F at the closest point. At this temperature the cover began to melt in about 1 Minute & produced a melting pattern very similar to the one caused by the Turbo:



I then tried re-running the test with a cover I had painted with a high-temp ceramic-embedded paint. This did seem to improve the behavior somewhat; it now took two minutes to get to the same level of melting:



Next I tried a section covered with the Foil:



I ran the torch for over three minutes this time and it showed absolutely no signs of melting. Furthermore, I tried to measure the inside temperature (a bit tricky) & I believe it stayed around 100F. Finally, in true Mythbusters fashion I decided to "crank things up a bit". I moved the torch a bit closer together & increased the flame on the torch:



With this setup the cover temperature reached 500F and the metal sheet got to 800F. I let it sit like this for over a minute. I only stopped it because it looked like the torch was about to burn through the metal sheet.






The end result looks like this:



i.e.....nothing. No bubbling, distortions, discolorations or anything else. Color me impressed. It's definitely going on the car!!


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Next up: wiring in a second battery & an update on the valve cover:

 

I could tell you, but then I'd have to...you know...:wink:

 

Oh all right, if you twist my arm:

It's heat reflective tape similar to what they use in F1. But this version is considerably cheaper than the F1 version....on the other hand the F1 variant is 97% reflective vs. 96% for this one.

Here's a link:

Heat Reflective Tape NEW!

 

Actually the mufflers aren't that expensive considering the lifespan (taking into account the repackability & quality of materials). I have the Stainless Steel Mesh filler. It's slightly heavier than the scrubble, but it's designed for absolute maximum endurance.

 

I'm constantly amazed at the depth and variety of Engineering that goes into a car. There's an infinite amount you can learn & do...if you're not limited by what you (currently) know.

 

Aluminum Valve Cover Update Part 1

Ok, after significant delay, here's an update on my Aluminum valve cover project. A huge thanks to Voigt Machine Inc. here in Houston for their extensive help in taking my vague ideas and getting them to work.

I simplified the design of the stock cover significantly - removing the built-in baffles and numerous extraneous curves & elements. I stuck with having a groove around the lip so that it uses the stock seal. And I found an off-the-shelf external valve cover vent with a built-in filter. It's a bit bulky but it works as a first cut.

Voigt was able to make it work on the first try. Here is what it looks like:





To seal around the spark plug tubes, I found an Aluminum baffle with inner and outer seals:



By cutting off the top it forms a perfect seal. You can see one installed in the images.



I have an old head I've used as a test block. Today I did a test install on the car to check all clearances. Here's what it looks like:









The good news is that it all looks good. The only adjustments I need to make are to trim off a bit of the bracket I made for the ignition coils. And I need to trim the rubber around the spark plug boots to fit better into the (slightly smaller and deeper) hole. I should be able to finish this up next week & start it up.

Now that I have a prototype, it's relatively easy to have more machined. Alternately, this could be used as a master for a cast version...

Thanks again to Jim & Craig at Voigt. They are miracle workers!!


More updates to come!