Anyone able to drill through their downpipe/midpipe to widen the gasket holes for the cat? What kind of bit did you use... I tried a 0.5 metal bit and it wouldn't go.

Thanks

 

Titanium bit I hear? anyone?

 

bump

 

I am slightly confused in what you are asking...can you rephrase it

 

ok so I needed to make the bolt holes wider on the downpipe as my stock cat wouldnt bolt up (the welded bolts are too narrow)...

I was trying to drill through the stainless steel with a larger bit to widen the hole but it wouldn't make any real damage.

Is there a special bit I can use?

 

 

i didnt have any trouble drilling mine out. make sure its a bit specificaly for drilling metal.

 

That's what I was thinking too, but there's not enough space between the "steps" in the step bit. Drilling through a 1/2'' flange would be impossible. Just use a standard type of drill bit. Cobalt or Titanium bits are awesome. Zirconium Nitride was the best, but not made anymore. Cutting lube and a good drill should get the job done. Buy two bits just in case. If it stops spraying metal pieces, then the bit took a $hit. Put the new bit on and continue.

 

Titanium/diamond dremel bit and lots of air from the air compressor! Dang my megan racing SS was tough! That's literally the toughest thing I've had to do.. nothing compared to porting!

 

could even be the drill is weak. evo150 what size/kind of bit did you use and how long did it take? Did you put the stock cat on or why did you have to widen the holes? Thanks

 

bump... planning on picking up a cobalt 0.5 inch standard bit tomorrow, would like more thoughts

 

i used a 1/2 inch black oxide drill bit that tapered to 1/4 inch ( my electric drill wouldnt take a half inch bit) i got at lowes. i had to drill out the holes in my downpipe to fit the bolts that came with my high flow cat. total time to drill out the 2 holes was probably 10 min.

 

buy a couple bits and step up in size so that each bit only need to remove a tiny bit. Cobalt works well but is expensive and brittle (wont matter for a 1/2 bit).

Make sure to use cutting fluid or some kind of oil at least.

Also get bits with a tappered point so that they will self center themselves.

 

Thank you very much.

I'm unaware of cutting fluid, can you link me?

Also can you show me what you mean by tapped point? Thanks so much!

Do you think this bit would work?

http://www.homedepot.com/webapp/wcs/...cStoreNum=8125

 

Here is cutting fluid

LINK

I meant to say tappered point. Basically the tip should be sloped so that the center of the bit will touch the metal first. This way it will center itself in the existing hole.


That bit you linked looks like it should work well. Cutting fluid or oil of some kind is a must.