Steam line Bolt Size for An or NPT Fitting
 

I researched the topic some and I seen some controversy on what size NPT or an fitting size goes into the back of the heads for the coolant crossover. I can get a kit for about $125 but I would rather do it myself b/c it will be cheaper and its not a Big deal to do.
I figured I would do a quick drawing using paint on what I want to do. I figured -6 lines would be perfect.
[IMG]http://i69.photobucket.com/albums/i7.../Anfitting.jpg[/IMG]

Re: Steam line Bolt Size for An or NPT Fitting
 

1/4-18 NPSF. That's a straight pipe fitting-not tapered.

Re: Steam line Bolt Size for An or NPT Fitting
 

You only need about a -4AN out of the heads and a -6AN coming out of the T

Re: Steam line Bolt Size for An or NPT Fitting
 

I bought 1/2 npt to 6an 90deg fittings.

I ran a 1/2 npt tap into the holes to make the fit a little better and just ran a few rounds of teflon tape around it.

I just didn't like the fit of the 1/2 npt in the hole due them being straight thread so I went the tap route.

Re: Steam line Bolt Size for An or NPT Fitting
 

GetaZforgetGT is yours doing fine with the 1/2 npt with Teflon tape,I read a thread and thats what Overton was doing.
The Factory has "O" ring's a washer and a nut built on to the part that goes into the head like a banjo fitting. Just wanting to kow if they both worked equally. I would hate for it to leak.

Re: Steam line Bolt Size for An or NPT Fitting
 

Yeah mine are doing just fine.
I would warn you that you need to use the tap effectively.
You need to keep test fitting until you have the 90 deg fitting oriented they way you want it. You just have to make sure that the fitting get tight right were you want it to end up pointing.

Re: Steam line Bolt Size for An or NPT Fitting
 

I did it without even running at 1/2-20 tap through. Just use 4 wraps of teflon and it will be fine. I have had mine running all summer and zero leaks. The hardest part was getting the -6 line onto the stock nipple on the radiator and then getting the -6 hose clamp on it. I only used it to look the same as the rest of the -6 in the engine bay, it was a PITA.

Re: Steam line Bolt Size for An or NPT Fitting
 

Yeah mine started but would only go in a few threads and I wasn't pleased with that so I had to tap mine a bit.
I have heard that others didn't need to tap it but I wasn't as fortunate.

Re: Steam line Bolt Size for An or NPT Fitting
 

Found some stuff i could use
http://store.summitracing.com/partde...5&autoview=sku

Or this one since it already has the hose end.
http://www.holley.com/849065ERL.asp

So you guys aren't messing with any type of crush washers, just screwing in the fitting with some teflon tape and being done with it?

Re: Steam line Bolt Size for An or NPT Fitting
 

Just 4 wraps of teflon on the fitting. The holley looks like an interesting piece, but the fact that they put a o-ring on there causes a little concern I guess. With a tapered thread it should seal on the thread not the o-ring. I guess it probably can't hurt but I would go with the (likely) cheaper way of doing things with the 1/2-20 to -6 90* fitting and then just make your -6 hose.

Re: Steam line Bolt Size for An or NPT Fitting
 

Yep I will just go with the Summit peice, and just get a hose end and connect the lines.

TQdrivenws6 did you get all the bugs worked out of the super Vic combo???
Hows the car running?

Re: Steam line Bolt Size for An or NPT Fitting
 

Still tackling things one at a time. I am headed to the track on Saturday and we will see what the latest changes have done.