1.8'* or 1.9'* better for a NA 3800?

Having said that, will the car need to be tuned after changing them out?

ZZP or Intense for purchasing purposes, or should I look at one of these other forums for a new (used) set?

thanks

The better a car breaths, the better you are. I say go big or go home, 1.9:1 If you can find a good deal on a used set, get them. $250 or so is a fare price. HS are good rockers, just make sure they have the new pedestals with a dot on them. You don't *NEED* a tune, but I would suggest it. Because the engine will flow better this will throw off the LTFT and cause the PCM to work harder to maintain the proper AFR.

Bigger is better on the boosted cars, but on the N/A motors balance will net more power, ZZP offers "ER Ratio Rockers" they are 1.85 on the intake and 1.8 on the exhaust and make more power then 1.9'* on both. Heres the link to ZZP but others offer split ratio rockers if you look around the big vendors.
ZZP Has an article you can download about the research that went into the different ratios, and their benefits.

Have you looked at the ZZP HV3 Insert yet? Its cheaper and offer the best bank for the buck for the N/A Guys!

is that insert in replace of new rockers or with the addition of new ones?

You could get the ZZP insert and make around the same power for about $100 less and its a way easier install, then down the road get the ER Rockers and be sitting around 75HP gain, then have someone like Dan (or even me and Tom depending on how well we get with it) Tune your car for the two and have a really good performing N/A car that is still as reliable as factory.

im curious to see a dyno with that insert in, its prety tempting for my dads lesabre

Here is the entire Dev write-up from easy performance

You can get the same effect of the HV3 by cutting your runners that are currently in your intake. Same effect.. nearly free.

I do agree completely with Trent on the ER rockers. Having the split ratio does give the NA a better get up and go a single ratio. Although if you really want some good power the GT1 cam is much better than the rockers.

Add a power log (after you research adn understand the cracking issue with both mild steel and stainless alike) for better flow. Most W body guys suggest headers over the log, but I say a log is fine as long as you realize the problems...probably buy a used one and have it fixed before installing.