Needwings intake manifolds are completely aftermarket units. I use the existing manifold and eliminate the biggest restriction which is the tiny tube leading up to the tank from the y-pipe. IMO, the tank size is of no restriction(ie the stock one is just fine). I managed to squeeze the stock intake on but do not have an sl55 intake to test fit, though im pretty sure it would work with minimum modification, if any. I also cant comment on if the engine cover will fit, but ill try to check that when i get home. These pieces provide a mostly stock appearance, but the power gains are amazing! I hate to embelish anything to much but this morning it was 58 degrees on the way to work and my car felt like it was on a small shot of constant nitrous. The traction control light even blinked at 65-70mph....i have never seen that happen before(not that im saying your car will do this lol). I simply could not stop flooring it all the way to work. The only other mod that gained me this much power was the 185mm pulley.

I will get pics up tonight, but they are the same pics that are in my other thread. I already put them up on MBWorld but for some reason these forums will not let you post the same pic in more than one place.