Not sure anyone knows this, but I'm trying to find the size of the female threads for the two vacuum fittings on the rear of the plenum located on the passenger side. I had the plenum powdercoated and the shop got just enough powdercoat into the threads so that I can't thread one of the fittings in. I'd like to buy only the correct taps to clean the threads. I'm trying to save some cash by not buying an entire tap and die set. While I'm at it, I'm also wondering about the thread size for the pcv connection on the driver side as well. If nobody knows this info, can somebody point me in the right direction on a way to find this info? I've already searched the threads. Thanks in advance.

 

On my '86, the brake booster hose fitting is 1/4" NPT. I'm not sure of the other fitting.

 

I'm about 95% sure the pcv fitting is 1/4 npt as well. If it's not that, it's a 3/8 npt, but I'm pretty sure it's 1/4 npt

 

I want to thank everyone who responded to my post. The fittings were 1/4" NPT. I found the tap I needed at OSH for around 7 bones. If I didn't have help from you guys I could've totally ran the wrong style tap through and ruined the plenum. This is just another example of how valuable these boards are. Thanks again. One last thing: I didn't get a chance to make my donation to thirdgen.org yet because times are tight (I just had a baby), so can anyone give me Dirk's email address so I can give something though Paypal?

 

glad to help, thats what the boards are here for

That reminds me, I still have to make a donation too...