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Discussion Starter · #1 ·
I've been hoping to tackle the intaking porting this weekend, but I can't seem to find the 4" carbide burr which is needed. I tried Lowes, Harbor Freight, and Sears. They all have stuff for dremmels, but not big air tools. Any suggestions of a store I might be missing..thanks?? I haven't tried Home Depot yet, but I figured they would be the same as Lowes.

Thanks.
 

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A 4" burr? What are you building up there? Try Shop Tools They are right off of west Garden of the Gods road on Elkton. If this is for a 32/36 I have one here.
 

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Discussion Starter · #3 ·
That is what RallyBob says to use to port the intake..1/2 inch Oval Headed carbide Burr, with 4 inch shank.. Maybe I confused a little..the 4 inches is the shaft length. I found one at Harbor Freight, but it was a 2 inch shaft, and wasn't carbide.

I'll check out Shop Tools...I think NAPA may have some also..they do online.
 

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Specialist Stuff

For specialist items like the carbide burr you mention try a Machine Tool supplier or a Foundary supply business. Home handyman, retail outlets are far less likely to have such and exotic item. If you work for someone with a Trade account you may even be able to purchase things with a company discount - that is how it works here anyway!
 

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I love this place

http://www.mcmaster.com/

Gotta love McMaster-Carr for wierd or hard to find tools too. Just hold tight on your wallet, there's thousands of dollars worth of cool stuff, tools and parts, available there.
 

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I seem to remember Summit racing having a head porting kit with a few burrs and some sanding rolls together at a decent price. Might be worth a look.
Jc
 

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I'm sorry Kevin I wish I would have known, I was at the high school in your town today and could have just dropped stuff off. Pretty funny as I started the day about a mile or two from Huskers house. For a change of pace I didn't drive by opelgtmasters place of work today. It is a small world when you start counting Opels.
 

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Discussion Starter · #8 ·
If you don't mind, and have the tools, I don't mind taking a drive to your neck of the woods tomorrow. It'll probably be quicker, than me running around all day tomorrow trying to find these things..plus its a nice little drive. Thanks.
 

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Carbide vs Stones

Carbide burrs are designed to remove metal at a high rate and will cut deeper per pass than mounted points ( "grind stones" ). The burrs can also be a bit of a handful to control too - the mind boggles at the thought of an unfamiliar person with a carbide burr that has a 4" shank ......... :eek:

With street porting very little metal needs to be removed from Opel CIH ports with most of the work being needed near the valves to dress up the short turn radius and opening out the valve throats for larger valves. Maybe a bit more metal needs to be removed from the combustion chamber to open up the area around the intake valve to unshroud that area - but a 2" burr will do that with more control.

A long shank carbide burr will probably be a relatively expensive item too.
 

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Jim, the reason for the relatively long carbide burr is for the access into the plenum of the intake manifold. A short burr will not allow full access, and will pretty much guarantee that the die grinder chuck hits and damages the carburetor mounting surface!

Don't forget, for an intake manifold, you need to get a more aggressive 'single cut' burr for grinding aluminum. Double cut burrs (for iron and steel) will clog unmercifully within 10-15 seconds and be rendered useless on aluminum.

Bob
 

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brake fluid too

You can also use mineral oil to help lubricate the burr and keep it cutting smoothly, but don't look too hard for it, just use some brake fluid.
 

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Kerosene works excellent too, I always had a coffee-can of it on my porting bench back in my grinding days.

Bob
 

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Kevin what I was trying to say was that I have one that is already done for a 32/36. I won't ever need it cause the hole is on the wrong side. I'm a side draft kind of person :rolleyes:
 

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Different metals - different tools!

RallyBob said:
Jim, the reason for the relatively long carbide burr is for the access into the plenum of the intake manifold. A short burr will not allow full access, and will pretty much guarantee that the die grinder chuck hits and damages the carburetor mounting surface!

Don't forget, for an intake manifold, you need to get a more aggressive 'single cut' burr for grinding aluminum. Double cut burrs (for iron and steel) will clog unmercifully within 10-15 seconds and be rendered useless on aluminum.

Bob
For initial removal of metal, get the right tool . . . like Bob says! :mad:
 

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Blitzed Again!

RallyBob said:
Jim, the reason for the relatively long carbide burr is for the access into the plenum of the intake manifold. A short burr will not allow full access, and will pretty much guarantee that the die grinder chuck hits and damages the carburetor mounting surface!

Don't forget, for an intake manifold, you need to get a more aggressive 'single cut' burr for grinding aluminum. Double cut burrs (for iron and steel) will clog unmercifully within 10-15 seconds and be rendered useless on aluminum.

Bob
Quite right Bob, I had interpreted "intake porting" as intake port in the head ... cutting cast iron ...... an "aged moment" for sure. :confused:

Carbide burrs with a single cut tooth profile and the use of a suitable lubricant - kero, diesel or even brake fluid!! - will be much more at home cutting the aluminium of the Intake Manifold. Certainly a long shank will be needed to reach way down into the radius of the arms of the runners.
Though the method of cutting out the bottom of the plenum to fit a machined, raised floor plug - as previously described on this site by another member - would allow much more access to the runners from beneath before the plug was refitted....... Something to think about and an advantage for that method of raising and filling the plenum floor.
 
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