glitchz71

iTrader: (1)

I know a lot of people use steam lines, drill the water pump housing or use the heater hoses, but I really like the way the APS twin kit comes out of the block and would make my install cleaner IMO.
I also understand they're not willing to sell their proprietary coolant drain plug adapter separate from the kit.
So my plan was to pull the plug, drill and tap it with some NPT treads, and solder an adapter to it, but in my searching online I found a drain plug adapter for a Honda B Series that is 28mm to -6an. Curious if anyone knows if they're the same thread. I may give it a try since it's only $35 and would save me the trouble of having to tap the stocker.
Not sure I'm allowed to post a link to it, but here's a picture of the adapter.

NoorJ

Those don't look like the correct threads to me. I would suggest having a fitting welded to the plug, not soldered.

glitchz71

iTrader: (1)

Just an update for anyone else curious about this. I contacted a seller on eBay explaining what I was looking for and asking if the thread would work for the LS engines. Unfortunately, he said its a different thread

Then he said he also sells some 28x1.25 thread (same as the LS plug) adapters that go to a -8an. I figure I can throw a reducer on there and be set. He said he sells them in a package, but will set up a listing for a single one for me to try out.

68LSA

Hey who has that fitting I need just a plug they. That coolant line gets in the way of my holley ls swap mounts was thinkin of just tig welding that hole closed

93camaro_zzz

iTrader: (13)

You could pretty easily just take a factory block off plug, and drill it, and take whatever size AN bulkhead adapter, and then weld it to it. Problem solved.

93batmobile

iTrader: (1)

I believe the factory plug is brass. I think that is why soldering was mentioned before.

nathanVY

What did the OP end up doing here? I'm having the exact same dilemma.

I bought a fitting that should be the same thread size but they look slightly different to me.

stevieturbo

Just drill/tap/weld/whatever. They're steel so it will be very easy.

nathanVY

Isn't the stock plug brass? My concern with drilling & tapping the stock plug is fitting it in afterwards the 17mm hex recesses a fair bit - need to run a -8AN fitting out of it. Have you seen any photos of it being done before?

stevieturbo

Not actually sure...I know when I got my new LS2 block it was bare, but I'm 99% sure the new bungs I got for it were steel.

One of the ones on my old LS2 block may ahve had a little colour to it as if brass though....but never paid much attention to material. Can check later.

nathanVY

enzed were able to solder a -8 fitting onto the stuck coolant plug, happy days!