Coffman Dry Pipe

[user_error]

I am looking for some information about this style of Coffman dry pipe. There doesn’t appear to be any decent sources online anywhere.

It looks like the pipe is a half-dry pipe and is to be used with water injection. Can anyone confirm?

Can a diagram be provided?

 

[MTRHEAD]

That’s cool. That’s considered a wet pipe by racing rules. Like the red pipe: dry until part way down the diffuser. Nice find!!

 

[user_error]

I figured it was pretty rare based on the lack of information available. It has a spray bar fitting on the top of the pipe that looks to be intended for water injection. I’d like to cap it and not run water injection. Based on the general knowledge of dry pipe routing it *appears* that this fitting could be capped and I could use standard dry pipe water line setup but I’d be grateful if someone could confirm.

 

[MTRHEAD]

I’m assuming somewhere is a hole in the stamping to let water in to cool the non water jacket portion. A riva red pipe has a hole that lots water in from the jacket into the chamber just before the non covered spot. Can you tell by blowing air into the jacket if it has a hole into the main chamber?

 

[user_error]

That’s correct, it does have a hole for water to cool the non-jacketed portion. It currently has a spray bar fitting that looks to be used with water injection

 

[user_error]

Here is how the water is fed into the pipe. It seems that this is definitely a half dry type setup because you determine that the first half of the pipe is jacketed while the second part is not. Water enters the bottom of the pipe in first picture. Water exits the jacketed portion at a port near the end of the jacketed section just around the other side of the pipe (not pictured). The water exit line runs to a T, of which one side feeds the stinger section of the pipe where the exhaust hose connects and the other side of the T runs to a bypass fitting. This all makes perfect sense to me.

I am only confused by the fitting shown in 3rd picture. I am not convinced it is necessary and the port can be plugged with a standard npt cap.