[ant_8u]

Hi guys

This is the intake manifold from my '71 Triumph GT6

Next to my thumb is a hole which requires filling

Is this possible to fill and make unnoticeable?

Also, what kind of finish should I go for on this manifold?
Painted or coated? Just cleaned up? Or flattes to remove the casting and polished?

[cobalt327]

If you just want to plug the hole, tap it for a pipe plug.

If you wanted the intake to be polished or have a natural finish of some sort- and for the plug to not show, use a plug made of the same metal as the intake is made of, and grind it even w/the intake.

From there, polish or sand/bead blast and/or paint as desired.

[eloc431962]

Originally Posted by cobalt327

If you just want to plug the hole, tap it for a pipe plug.

If you wanted the intake to be polished or have a natural finish of some sort- and for the plug to not show, use a plug made of the same metal as the intake is made of, and grind it even w/the intake.

From there, polish or sand/bead blast and/or paint as desired.

X2 this is what i would do also.



Cole

[ant_8u]

I'd like to remove all traces of the hole

It's already been tapped

If I decided to keep the cast look how would I grind it to give it a cast look and not see the outline?

What's the best way to polish cast alloy like this?
Machine, or by hand? And what should I use?

Thanks everyone

[matts37chev]

i love polished aluminum, but it will have to be done with a machine and will be alot of work to keep it nice.

if you want to polish it, no matter what you do to that hole it will still show up.
even if you weld it and grind it smooth, the hardness of the weld and the cast manifold will have different look.

i agree with just put a plug in it, but get a nice looking plug so it doesn't look like a wart on there.
(you are building this car so nice, no one will see that, they will be too busy looking at everything else)

paint on intake manifolds is bad, the gas always eats it off sooner or later.

the easy way to make it look nice and last a long time, is to sandblast it, and then have powder coated clear.

[cobalt327]

Originally Posted by ant_8u

I'd like to remove all traces of the hole

It's already been tapped

If I decided to keep the cast look how would I grind it to give it a cast look and not see the outline?

What's the best way to polish cast alloy like this?
Machine, or by hand? And what should I use?

Thanks everyone

You could easily polish intake yourself if you have access to a bench grinder of 1/3 HP or more. HERE'S a page on metal polishing.

The polishing compounds and wheels are readily available from the interweb or from tool supply outlets.

Keeping the finish prestine IS a problem, like Matt said, but not an insurmountable one- you could clear coat the polished surface using a high temp clear engine paint. This will dull and can even discolor over time, so bead blasting/clear coating might be a better solution.

Aluminum alloy can also be anodised any color you can imagine, but I would powder coat it if I were to want it painted.

[cobalt327]

Several of the companies HERE list plugs in chrome and stainless, as well as colors.

You could plumb in a vacuum gauge, even. Handy thing to have when you're tuning the engine. Two birds w/one stone.

[matts37chev]

if you decide you want to polish it i can give you some tips and point you in the right direction for some tools and products

i do ALOT of polishing for myself and other people
i really enjoy seeing something old and crusty like that intake turn into a piece of jewelry

heres a pic of a quick bit of fooling around with my tunnel ram

[ant_8u]

Oooooooo.....shiney shiney!

Can you powdercoat mirror polished metal, or does it need blasting so it has a key

What do you think about these reservoirs?

High polish, or just cleaned up back to stock?

[matts37chev]

you can make them shiney, but powder coating needs rough surface to stick well.

once you get something really polished well, its not that hard to keep shiney, but you do have to do the maintenance work and it does take some effort but the more you keep up on it the easier it is.

there are some polished alum. sealers, like Zoopseal http://www.zoopseal.com/ but i have never used any of them, and they are very expensive.

when you are polishing anything, all you are doing is sanding it so smooth its mirror like.
this requires you to sand down the whole thing to the bottom of the deepest pit/corrosion or at least blend it to the surroundings.
this can make things very thin when you are done if they are pitted deeply

[Commanderkewl]

I would vote for the powder coated route. It does hold it's appearance for a bit longer, I like the lack of maintainence required to keep it clean.

I love my billet specialties serpentine system but it's starting To fade (dirty) and it looks like it will need a Zoops cleaning/polishing to get her right with the world once again.

You blast it, powder coat sticks.

[matts37chev]

Originally Posted by cobalt327

You could easily polish intake yourself if you have access to a bench grinder of 1/3 HP or more. HERE'S a page on metal polishing.

The polishing compounds and wheels are readily available from the interweb or from tool supply outlets.

Keeping the finish prestine IS a problem, like Matt said, but not an insurmountable one- you could clear coat the polished surface using a high temp clear engine paint. This will dull and can even discolor over time, so bead blasting/clear coating might be a better solution.

Aluminum alloy can also be anodised any color you can imagine, but I would powder coat it if I were to want it painted.

thats some good stuff on that site!

[Silverback]

WRT to making it look stock, put an aluminum plug in there or weld it, then grind it flat, take a fairly coarse sanding disk and hold it over the surface and hit it with a hammer, if you get it right (and sanding disks tend to work better than similar sand paper, don't know why, they just do, probably something different about the adhesive or something) the impact marks will look a lot like a rough casting (adjust the sanding disk grit to get the correct casting roughness). At that point hit the whole thing with a bead blaster or a caustic or acidic aluminum cleaner (mag wheel cleaner, toilet bowl cleaner, even oven cleaner...) and it will match the color up (be careful with the chemicals, some older castings that have a lot of junk in them can discolor with them if you leave them on too long).