I have a 2000 SSEi with a 3.25 pulley, 180 thermostat and cooler plugs. I am looking to upgrade the rocker arms. I see the steel arms are a 1.9 ratio and the aluminum arms are 1.8 ratio. Which are the better arms and is there a noticeable difference between the two types?

I dunno but Im courious of the ans too

The 1.9 ratio are going to give you more lift, whereas the aluminum ones give you less lift but generate less friction because they are full roller rocker arms. INTENSE used to make full roller 1.9 rocker arms but had many problems with them. The SLP 1.8'* haven't been out too long, so the same problems may arise in the future. The 1.9'* are the stock rocker arms re-worked, so basically it is of OEM quality so you know you aren't hurting your reliability over the stock ones because they are basically the same.

Personally it seems that the 1.9 would be much better than the 1.8'* because of the fact that they have MUCH MORE lift. The 1.9 rockers have .4902 lift, whereas the 1.8'* only have .4644. Stock is .4128, so you can see it is a HUGE difference. I would recommend the 1.9'*, our GTP is the second fastest stock cammed GTP out there and it has 1.9 rockers, and so does the only one that is faster than it, basically because the larger rockers are like having a larger cam.

Hope this helps.

Oh yeah, 1 more thing, unless you plan on doing headers along with the rockers the 3.25 pulley you have is probably too small for your mods, and your car would mostlikely be faster with a 3.4 pulley.