2 piece dry stack

[Gmcviper]

When dry stacking a 2 piece adaptor when you drill these holes and plug the hole under the poppet, you basically disable the poppet and force all the water through the motor?

[FORBESAUTO]

There’s a handful of ways to do it. When I plug the poppet dump hole, I drill and tap a hole in this area and run hose out back of cowl to dump the poppet externally. You have to dump it or water pressure will be through the roof. You can also play with size of dump fittings/hose to control pressure (if your fittings/hose are too restrictive, you’ll have too much pressure at wot.

[Gmcviper]

Ok. So where the holes are in the picture you would need restrictors or you wouldn't build any pressure?

[FORBESAUTO]

Ahh, just saw where they where drilling holes. The way they are showing it looks to be eliminating poppet and control water going into motor kinda like a one piece and vary oriface of fittings to control pressure. The way I showed is you is only diverting poppet discharge externally and do not need any extra holes and the poppet still operates like originally, only dumps outside and not in mid.

[Gmcviper]

Thanks that's what I was thinking. I'm going to do it your way.

[FORBESAUTO]

Just try to keep your discharge fittings and hoses ID around same size ans hole your plugging. Any smaller and you’ll get too much water pressure. There’s two small drain holes in rear of plate, let them be, need them to cool can, tuner and water pump. Can also drill a small hole in your plug for original poppet dump angled toward water pump to cool it. I‘Ve ran em with only the two rear holes with no issues or water pump problems. But a little spray to cool can’t hurt and aint gonna effect power.

[Gmcviper]

Got ya. I already drilled a 1/16" hole in the poppet dump plug to keep water pump cool. I welded the 4 holes behind the tuner and drilled a 1/8" hole on either side.

[Merc 2.5]

Question guys,,,, what does this drystacking 2 piece plate do for the mota? Yep. Rook question I guess

[FORBESAUTO]

Helps a little in reducing back pressure and distorted exhaust flow by eliminating water in can. Also allows a little more temperature on the tuner which causes speed of scavanging waves to be a little quicker for higher rpms. Is it a major difference? Na, but every little bit counts. If ya have the holes in floor of your can and your getting up on plane you’ll notice a significant jump in rpm and power when the holes clear the water (at least on a heavier rig anyway), same idea

[Merc 2.5]

In dummy words. If can/mid is drilled for exhaust relief?

[FORBESAUTO]

Yep

[Gmcviper]

Can plug this hose or do I need to T it in on one off the dump lines?

[FORBESAUTO]

That’s the one on the rear of the plate right? I’m kinda lost on where I’m at lol. If it is, then it’s the one that T-ed into your tattle tell. You can plug it, or T- it in, whatever floats ya boat. I plugged mine and just run the two thermostat dump hoses and the poppet dump out the rear of the cowl.

[Gmcviper]

Yes it was T'd into the telltale. I'll plug it then.

[FORBESAUTO]

I have one motor with it dumping and one without, not much of a noticeable difference. It does drop pressure just a few pounds with it dumping, but from what I can remember from playing with it, it’s not a significant difference. Said all that to let ya know if ya pressure is a little high, you can lower it a tad by letting it dump.