The one that goes on the injector pod not under the entire unit.

I can get around $12 shipped to me.

Anyone have any experince with them?

And how hard to install.

 

A flat base airfilter housing should give you 20x more gain.
If you are using the stock air cleaner with cut away silencer ring it allows a little more air in. But you could use the 12$ to make it a flat base.

 

i had just recently put that injector spacer on my car it only talkes about 10 min. but its a pain in the *** to get the fule lines screwed back in but idk if its worth it beause when i was installing it i cracked my injector pod so idk if it is worth the money or not.

 

I have done it, its a pain in the butt actually because of the fuel lines, you really need to put new orings and the lines and you should use a proper line wrench and i didnt really feel any hp difference its just a mixture of a couple things that give your car HP. I just put a hypertech powercharger and kn flowthrough top filter on it and now i feel a nice HP gain, or seat of the pants throttle change.