Right size tap for C4 panfill dipstick?

[Proeliator]

I've ran into kind of an odd situation. I have a '75 EB with the factory C4, the dipstick screws into the pan, rather than joining at the body of the C4. I've bought a new aluminum TrickFlow aluminum pan which was supposed to be a panfill, its not. No big deal, I figure I'll just drill and tap it for my old dipstick.

Here's the weird thing: The bung in the factory pan, and the threads on the end of the dipstick are slightly larger than your standard 1/2 npt, as well as the thread being at a 18 tpi. Wtf!? Every 1/2 and up tap I've ever seen was 14 tpi. Any idea on what the heck size/type tap I need to be using? Its like I need to use a 9/16 18tpi tap but that doesn't exist. I'm at a loss what the heck Ford did here...

 

[brewchief]

Isn't the end of the dipstick a big inverted flare? When I first did up my c-4 I remember the trans guy having a hard time finding a fitting to make it work.


Brewchief;D

 

[bobbyray27]

What type of threads are we woking with, pipe, compression or standard bolt threads.

 

[Proeliator]

The long and the short of it is that I'll need to be using this: http://store.summitracing.com/egnse...inresults=false&Ntk=KeywordSearch&DDS=1&N=115

 

[garberz]

For an aluminum pan you need to use an adapter. Pan should be tapped tapered pipe thread. The dipstick tube is a flare. Adapter in between the two. I'm not sure of the exact size. here's a pic from summit. Maybe they would sell it separately? http://store.summitracing.com/partdetail.asp?autofilter=1&part=PMA%2DPA26404&N=700+400062+4294922122+115&autoview=sku

 

[garberz]

The long and the short of it is that I'll need to be using this: http://store.summitracing.com/egnse...inresults=false&Ntk=KeywordSearch&DDS=1&N=115

Well there you go. I was looking, I couldn't find it. Your good!