Goughary

I'm considering pulling it out of the attic and giving it a go.

RicardoD

EDIT: i see the photos in post #229, and it was what i was expecting, a link bar to connect the two flaps. Now I wonder if it was cost or function that drove the change, and when they finally re-tooled to plastic they centered the flap.


When I get mine back together I will definitely evaluate the vacuum to actuate

Goughary

Meanwhile, back at the farm, i wondering why we don't all paint the insides of our manifolds glossy Mexico Blue...

willmip

This sounds like lockdown madness more than intake madness......

Peteinjp

I was thinking the exact same thing! So smooth looking. And the red edges. Madness is definitely in effect~

Kinda like X-files Cerulean Blue meets Pepto-Bismol,.

Pete

Goughary

I know we are kidding - but someone who reads this will take it seriously- so just that it be said---

Please don't think it's a good idea to paint the insides of the intake. You will destroy your motor.

----

End of disclaimer. Back to normal banter and current insanity (madness)...

RicardoD

I've seen the throttle body referenced elsewhere as magnesium and Anthony's 98.975% eye says it is mag so I did one more test. I dunked the throttle body in a bucket of water, filled to the brim, and then measured how much overflow of water was displaced. This method said the throttle body is about ~675ml (cm^3) of volume. (yes, madness)

Aluminum density is 2.7 g/cm³ x 675 cm^3 = 1823g
Mag density is 1.738 g/cm³ x 675cm^3 = 1174g

When I weigh my throttle body I get 1387g which is much closer to magnesium. So magnesium it is for me.

So when I start to sand the throttle body and eliminate the black outer layer is there a risk of corrosion? The inside of the throttle body itself doesn't seem like a highly corrosive environment and I will end up putting Cerakote on the outside. The question is what to treat the inside with if at all. Don't need flakes coming off and right into the cylinders.

Goughary

Good points...

While we wait for the resident expert...excchhemmmm,,,,,Anthony...to chime in...

Here is the dual resonance flap unit i have from my box of intakes in the attic. I have five or six more but this is the only one with two flaps. And the only one I've ever come across - I've never seen one on a car. But now that i say that, it'll probably be the next early car in my garage (after the RSA that showed up yesterday -



And here is the nasty old throttle body that needs a good going through...

RicardoD

Ooooooooooo..... dual resonance flaps, my precious.

Goughary

Ricardo. What are you using to test the pressure on the actuator for the resonance flap? I was thinking to get the same sort of thing to test the dual flap version for comparison. After it's been cleaned and has new bearings. Right now it's almost impossible to move it's so gunked up.

RicardoD

I bought the cheapest vacuum brake bleeder kit I could find on amazon. $22

I still don't have my bearing and have yet to start the polish job on the throttle body. I am a couple a weeks away from measurement.

cobalt

Cool stuff guys. It is amazing that as much knowledge I have accumulated about these cars there is always something else to learn. I was busy this weekend with mothers day and my son's virtual graduation from College. He was happy and sad all at the same time, missing out on a very important time in his life. Although he is grateful he has it is good as he does as others suffer.

As far as corrosion and the mag parts. If it has turned black or gray it is usually more susceptible to flaring up when grinding or polishing. The powdery salts you see in white I would be careful with. An acid bath or some form of grit blasting prior would help eliminate that although the material will be missing when done. This is corrosion down the the dendritic level. As far as finishing it appears people are having good results with Cerakote. If I still had the foundry it would have a chemical conversion or acid pickle done prior to painting the outside. A simple mixture of Sodium dichromate, nitric acid and water will make a simple acid pickle where the acid etches the surface and the dichromate makes a skin protecting the mag and prepping the surface for paint . Nasty stuff and always remember to add acid to water. It is a carcinogen (ask me how I know) so it isn't worth messing with unless you are extremely careful and have all the proper safety equipment. The inside should be moisture free for the most part so I would think it would handle it better than the outside which gets wet and exposed to some elements. I might consider a washprimer spray on the inside, very light coat to help keep it from corroding. It will etch and bond to the surface. Sikkens makes a nice rattle can version.

Good question on why they used the two flap design vs a single unit. I don't see what advantage it would make.

RicardoD

Thanks Anthony and congrats on your son's graduation. All the graduates this year (my son finishing high school) are really getting the short end of the stick. Big life events to be celebrates by families.

Back to our madness to keep us sane in these times....

I received my Cerakote swatches of interest today. This is an impossible task to photograph and white balance properly but this is good enough. That's why you order free swatches and pay for shipping. Each swatch has its own flake size to see how it reflects the light. Tactical gray is what I like best for the throttle body and may coat the intake plenums with glacier silver.

Goughary

I like it!

It's too bad the color choices for the air dry options are limited. That's going to look really good though!

I'm curious if we can Cerakote the inside of the throttle body- can the coating come off like a painted surface?

spartansix

Cerakote should not chip or flake... but it can if the surface isn't properly prepped. I'm not sure I'd risk it, especially since it would mean sucking some really hard stuff into your motor.