I don't want to start a pissing match over who makes the best plate but I'm having problems with a used HSW plate kit that I purchased a while back and my problems are more than likely installer error rather than manufacturer quality. I have all the parts installed and lines ran but the bottle is empty and I haven't wired anything up yet.
First off this is installed on a stock dbw tb with the stock intake. The "OEM" gasket installed on the plate does not match the gasket installed on the stock intake so I started thinking that maybe I bought a plate for a 78mm LS1/6 car but in my research I have found that the sku # is identical between the trucks, f-bodies, GTO's, and from what I understand the only difference in these and the C5 kits are solenoid mounting bracket related.
Long story short, after installing the plate my truck idles like and transitional/coast down idle while cold is impossible. After the truck warms up to operating temp it does much better but it seems to want to idle around 850 rpm and I have it commanded to 750 and for some reason idle timing is around 20* when I am commanding 24*. Exhaust tone is definitely different at idle and while driving as well. I tried spraying some cleaner around the plate, solenoids, lines, etc to check for vacuum leaks and didn't find any, then I loosened and tried to reseat the plate and TB but this didn't help either. Has anyone else had problems like this with a plate?

 

i would start by calling HSW. maybe they've run into this before and know the solution.

 

I have the Nitrous Outlet plate (which I love and truly believe is one of the better plates available). That said, the HSW plate should work for you. One thing I noticed in your post is you stated the gaskets don't line up. They aren't suppose to line up. The stock intake gasket goes on the flat side of the plate and the plate gasket goes against the TB. Is this how you installed it? Almost sound like you have it reversed.

 

Good luck getting any help from HSW

I don't have anything more to add than that. Sorry

 

I had it flipped around the right way. I reseated everything again this evening and I guess I was holding my mouth just right. I also reverted to a known good idle airflow tune and that helped drivability a lot. I'm seeing some crazy stuff in my idle air logs but that's for a different thread
I checked out the other truck plates and none of them have provisions for the tb pcv inlet...why is this?

 

Do you have the fuel and nitrous inlets sealed up? I've seen people install plates and leave the hoses off and it basically creates a vacuum leak straight into the intake tract....

 

Yep, all the lines are hooked up and snugged down.

 

what about the possibility of a solinoid leaking or being stuck open causeing a vaccume leak?
Creating the idle issues