I know that a number of individuals who regularly post here have the World Products Heads, so someone has to have faced this before. Here goes. The tapped holes for the temp sending unit and the fan switch are slightly larger than the stock sender and switch. I believe that the cts and fan switch are 3/8 npt and the holes might be 1/2 npt, but I'm not sure. Question #1: do adapters exist that will allow me to use my stock cts and fan switch? Question #2: If they do, what are they called? Are they 1/2 npt to 3/8 npt adapters, or something like that? Any input would be greatly appreciated. Thanks very much.

 

I have a set of world torquer heads, and yes I dealt with the same problem. I went to advanced auto parts and, they sell them there. I don't remember the exact size, but I think you are correct 1/2"-3/8" NPT. Your local auto parts sells them. Hope that helps.

 

It's called a pipe bushing.

 

I appreciate your responses. I figured that I wasn't the only one in this position. World's site claims that their tapped holes are 3/8 npt, but considering how outdated that their information is, it's not surprising that this may be incorrect. My Vortech uses a 3/8 npt fitting in the oil pan as a return line drain, and it looks smaller than those holes in the World heads. Anyway, I'll start with the local parts stores. Thanks again.

 

Why do you say their information is outdated?

 

Tony89,
Lowes and Home Depot will have what you need for less than one(1) dollar! They will have them in Galvanized, Black Pipe, Stainless (maybe?), and in Brass.

I would extremely highly recommend using the brass to avoid any dissimiliar metal corrosion issues with your heads.

Sincerely,
Kurt

 

Just yesterday, I got a pair of these in brass. They work perfectly. Thanks to all of you for putting an end to my little crisis. As for why their information is outdated, I'm referring to their tech sheet in PDF regarding the S/R Torquers.

When I bought the heads in March of '04, I was under the assumption that I'd have to (1) have the EGR passages drilled, (2) have the perimeter valve cover bolt bosses milled down, and that the temp. sender holes were 3/8 npt. Much to my surprise, the EGR holes were cast in already, the perimeter bolt bosses for the valve covers were already milled down, and for some unknown reason, the water jacket holes are 1/2 npt. As of a couple of days ago, the information in their tech bulletin on their site still reflects these "facts." In the grand scheme of things, that last point about the temp. sender holes being too big barely registers on the radar screen. I truly hope that's the worst problem I ever have with this car, or anything else for that matter. Anyway, thanks to all of you again for your imput.

 

Is this the sheet? http://www.worldcastings.com/docs/05_cat_pg16.pdf

The ports on Chevy heads haven't always been 3/8", they were originally 1/2". It's a lot nicer to use a bushing to put a 3/8" sender into a 1/2" hole than it is to put a 1/2" sender into a 3/8" hole.

 

Actually, no. The tech sheet is under the Tech section I believe. It has all of the vital statistics on the cylinder heads. It is here that all of the things I mentioned are spoken about. The page you whose link you included in your post is actually the catalogue page.