Drilling Carb Jets

**oldschool_mr18RG** · 03-01-2008, 01:12 PM

hey guys , you can get what you call numbered drills that you will be able to get from
industrail hardware/blackwoods, i think there in most states...... cause i have them a set and thats what i did when i was told by many..... you could not run 21psi through two solex carby's on an 18RG

Cliff .. 18RG HKS 21psi

**MWP** · 03-01-2008, 02:47 PM

Jaycar, Dicksmiths, etc sell small drill sets used for drilling PCBs.
Ive used these in a dremel along with normal electronics solder on my jets.

You dont need lots of different sizes either.
Drill out to a larger size first, then solder, then redrill with a small drill.
If you need a slightly larger hole, its then easy to use that same small drill to ream out the hole to a larger size since the solder is quite soft.

Ive been running the jets in my Weber 34ADM for ~5yrs now with no problems.

**oldcorollas** · 03-01-2008, 04:31 PM

hmm.. oxy tip cleaning rod things to finish to a size?
http://www.welding.com.au/products-w...iProductID=155
no idea if that is a good idea tho

**PULSE** · 06-01-2008, 11:11 AM

The micro tools links that you posted rodger are perfect. It's less than $20 all up delivered to your door. Its just a pity I don't have a credit card, I hate when sites dont have any other payment options. If anyone else is planning to buy anything from there I could pay them in advance if they get my stuff too?

**thechuckster** · 06-01-2008, 01:39 PM

rather than lead/tin solder - you could braze (silver-solder) the jets and re-drill. would be a tuffer material/

**bnicho** · 06-01-2008, 05:13 PM

What's wrong with buying the proper jets? Why mess around bodging up inaccurate sizes?

Drilled jets are painful down the track when you or the next owner of the car/carby need to change them and they don't know what size you drilled them out to. Even worse if the number on the side is still there. I have one marked 135 that has been drilled to about 170. I fitted it and wondered why going from a 140 to a 135 made the car run RICHER!

If you have a fairly standard combo (eg: DGV on a 2T) there should be someone on the forum who can tell you what they used. Buy a jet either side of their specs and experiment and you should be close. If you have a decent dyno shop jet the carb for you they should have the jets in stock and charge you only for the ones you use anyway.

A mate and I used to keep a "library" of DGV jets we had built up over the years. When either of us used one we replaced it so we always had a full set.

**MWP** · 06-01-2008, 09:39 PM

Originally Posted by thechuckster

rather than lead/tin solder - you could braze (silver-solder) the jets and re-drill. would be a tuffer material/

No need, its only fuel running through there and at rather low pressures.
Normal solder wont be going anywhere.

What's wrong with buying the proper jets? Why mess around bodging up inaccurate sizes?

Cos its quick and easy?
IIRC, last time i went looking for a weber jet kit, its wasnt cheap.

I installed the Weber 34ADM on my 18R (then later 21R) for the total price of $50 (that incl the carb).
Jet kits were a hell of a lot more than that (yes, im a cheap ass).

**Steve M** · 07-01-2008, 12:30 AM

Working with solexes was a bt easier as the jets are basically bolts, so I just modified some brass bolts and drilled them and marked their sizes.
I got my drills in .05mm increments from General Tools in Adelaide.
Weber jets are a little different from the one set I've seen.

**big wad** · 07-01-2008, 07:14 PM

just go to a cig shop and ask for a set of tip cleaning drills, all the old speedway blokes have been using them for jet drills for years. i havent read the other page of messages so someone has probably already told you, or i can send you a new set real cheap. cheers bigwad