I have never driven the L67 or 4.0 V8, only a L36 3800 N/SC. My questions are:

1. Is there A great deal of difference in performance between the L36 and L67?

2. How does the L67 perform in such a heavy car like the 2000 SSEi? And does it really deliver the V8 power everyone says it does?

3. How does the 4.0 V8 Perform in the '01 aurora for comparison?

4. Which do you prefer?

the L67 is the supercharged version of the L36, with almost 40 more hp. Its got a strong low end. The 4.0 v8 is DOHC and its more of a revver wth a stronger mid-top end and 10 more hp than the L67. In a drag race, stock for stock, the 4.0 will have an advantage. The L67 has a larger aftermarket than either. There are a few members here who have owned both so thay can tell you which they prefer.

I have driven all of the above .

1. Is there A great deal of difference in performance between the L36 and L67?

Yes the L67 puts out much more power than the L36. its power you feel in the seat.

2. How does the L67 perform in such a heavy car like the 2000 SSEi? And does it really deliver the V8 power everyone says it does?

The L67 will make a car like a 2000 ssei feel smaller with all the power it has. Passing power of these motors is what makes the L67 so Desirable.

3. How does the 4.0 V8 Perform in the '01 aurora for comparison?
First of th 4.0 is a quad cam motor. Power in the down low is modest but the fun for these cars are on the highway. Just don't expect much of a aftermarket for these motors and to be able to do a burnout.

4. Which do you prefer?

L67 by far. I have a 1995 Buick riviera with a Ser 1 L67 and I have friends
who swear my car has a V8 (when I open the hood they are shocked)

I believe that the L67 would have the advantage due to the instant power you get. The northstar has all the power at the ceiling. In a drag race. The L67 would have the advantage.

auroras are slow.
i prefer the L67 for reliability, performance, and good aftermarket, however, for some reason the 4.0 aurora feels much torquier but doesnt perform nearly as well as it should. it has huge potential but falls a bit flat

L67 owns 4.0. theres no whine with the 4.0.

All in the taste of the driver. For the true performance nut, the L67 is the way to go. If you like a cruise, get a set of Magnaflows for the 4.0, the sound alone will give anyone a smile. I've driven all three.

I've driven all 3 as well. The L67 > all. Easy to get 300+ HP out of with simple bolt-ons. And it makes as much torque if not more torque than a lot of V8'*.

Please not that ToastedOats OWNS both cars currently. His comments speak volumes.

You guys make me jealous :(