Flared aluminum intake trumpets.

[MonoPed]

I recieved an email asking about the intake trumpets on a Cobra I built, so I decided to post a short how-to. Now, if you have, and can use a lathe to turn these, great. But if you are a mere mortal like myself, here's a quick and easy method for ya.

You will need some aluminum tube, a sharp knife or small tubing cutter, small hammer, an anvil of some sort, and a small punch.

First, cut the tube to the desired length. Mile-high stacks might present a problem, so keep it reasonable. I use a larger X-Acto knife with a curved blade for this.

After cleaning any flash from the cut, place the tube upright on the anvil, and place the punch in the end. Give several light taps untill you have the desired flare, and it is flared evenly

And here is the finished trumpet.

If you're after a polished look, try polishing a longer piece of tubing, then cut to length and flare. To avoid any marring on the inside of the flare, you can try polishing the punch. Hope y'all find this useful,

Brian

Edit: Moved pics to new server

[S10man]

Thanks Brian. That is exactly the information I was looking for. I appreciate the quick response.

[weasel]

hey Bri... how long can ya' make them before they kink when tapped, say the long tubes for a small block??

[MonoPed]

The ones I made were for a road racer, so they were short. I really don't know how long they can be before things go south. If you want to make longer ones, try cutting to the desired length, then slipping it inside a slightly shorter piece of tubing the next size up. That might keep it from bending or kinking in the middle.

[weasel]

the man with the plan.... [slaps forehead] why didn't i think of that.....

[MonoPed]

Now that I think about it, a better idea for longer stacks would be to mill a piece of hardwood - mill the thickness fo the wood to the length of the stacks, drill a hole for the tube, and use a counter sink to allow room for the tube to flare.

[S10man]

Now that I think about it, a better idea for longer stacks would be to mill a piece of hardwood - mill the thickness fo the wood to the length of the stacks, drill a hole for the tube, and use a counter sink to allow room for the tube to flare.

Now that's brilliant. Thanks.

[Dag]

Great tip, if I might add one thing. If you heat ( aneal ) the tubing it will be a bit softer and easier to shape

[MonoPed]

Good idea Dag. Can the anealed aluminum be polished as normal?

[slotbaker]

Great ideas on this forum.

You could also use a small ball bearing to tap into the end of the tube, and it gives a nice smooth result as well.

The annealed tube should polish up just the same as before.

[Dag]

Good idea Dag. Can the anealed aluminum be polished as normal?

Like slotbaker said it should not affect the ability to polish.

Are you a rock hound? Just curious, thats a rock hammer on the pic isn't it?

[MonoPed]

No idea what type of hammer that is.....been in the tool box for a loooong time.

[camaroman]

That hammer looks like a brick masons' hammer, possibly made by Estwing.The pick end was used to score and break brick in the days before the portable saws they used nowadays .

BTW, Nice tip!

[MonoPed]

That's a sharp pair of eyes you have - it does indeed have Estwing on the handle.

[camaroman]

Nah! The eyes aren't that sharp.

The shape of the handle is almost like a trademark with those folks. And I have spent the last 21 years of my life in hardware stores, both working in them and selling to them.

[One_Track_Mind]

Like slotbaker said it should not affect the ability to polish.

Are you a rock hound? Just curious, thats a rock hammer on the pic isn't it?

I would tend to believe the hammer would be used for a tinnerman in the hvac trade. :|

Nice tip for those going for the full custom look.

Thanks for sharing. 8)

[walt francis]

Now I can do my headers