I'm considering mounting a conservatively sized turbo on the cross over pipe near the throttle body. The car is a 89 LN3 that will be getting a L27 Upper Swap soon, hopefully with some L67 injectors.

If I do so, where should I drill my oil feed line? Who could I go to for tuning my ECM? How much boost could I run on stock internals, non-intercooled?

And depending on how things work out, I would consider mounting the turbo, and seeing if I could run a couple of pounds on the LN3 intake, stock injectors, and stock tune.

I say use a leaf blower for a turbo..then you have self contained oiling system and its pretty big.....Lol.just run a lever from your throttle cable to the cable on the leaf blower and ur good to go...lol

Im not sure how a turbo set up would work out on your car..If it were me sense your l27ing the top end why not SC it

There isn't enough supercharged series 1 cars in my area, and there is pretty much none for parts. I guess none of the locals bought any with all the Marijuana money floating around in the 90'*. They all bought trucks.

I'm a little more familiar with turbos, and its easier for me to splice the exhaust and fabricate a little than trying to track down a supercharged car.

Okay..It was a suggestion but in that case..I am sorry but i dont play with turbos much im more of an SC guy...So i will step down and let somebody more familiar with turbos help you out...
Although i do have one question.Having a 4t40 trans do you plan to somehow make it stronger first

Did somebody say turbo?

LOL, Let me do some research and I'll get back to ya.

Looks like the best turbo for your motor would be a Garrett T3 52 trim (link) or a 60 trim T04E (link). I would go for the T04E because they are a lot cheaper, but you also get what you pay for.

I don't know about the 3800 blocks, but I got my oil feed next to the oil filter where an oil pressure sensor would be. I drilled and tapped my oil pan for a return line.

As far as tuning, I'm using a Megasquirt stand alone engine management computer. But that'* a lot of work. I don't know a whole lot about the 3800s but I would say grab the engine harness and computer from a series1 L67. Make sure you get the MAP sensor too.

Here is a link to an actual turbo build on a 91SSE

https://www.gmforum.com/your-ride-gm-pictures-videos-89/black-magic-1991-sse-turbo-217932/

Please DO NOT post in this thread, as this member is long gone. Seems like the pictures are gone too however.

Am i the only one afraid for the 4t40s life or am i just paranoid because all but one ive had have died out at a young age with no real power adders or bein beat on

Valid point. If you do this, consider your transmission fragged. Save up for the build up!

The trans will blow only if you don't take care of it. Best things to do is make sure it'* got fresh fluid and a clean filter, install a trans cooler. Don't spin the tires when turning, ease off the gas when it shifts gears etc...

I'm dealing with the same concerns. 300lbft of torque at a 4t60 is never a good thing. I've got an external trans cooler mounted in front of the intercooler so it gets the coolest, freshest air.