Need help on Turbocharging a 318

srixon4406 would be correct. Go over to theturboforums.com and start some research over there. Like he said the response time is sometimes very slow. You can also just do searches and find out alot of stuff pretty quick there is MEGA information over there.

I was going to say you should get new turbo's also but I figured you wanted to start with what you have. I do know that 1 of the turbo's I am running would be a good size for your 318 and the cost is not that bad at $260.00, it is a 70mm with 1.05ar. There are guys with 5.3 Chevy's making 600RWHP with one of them. I am sure your 318 could do at least the same with some good tuning.

67Dart273 has a good idea also and this may a real good alternative by getting a set of Chevy Turbo Headers and welding on new flanges. Just make sure they clear the inner fender wells before you hack on them incase you need to return them. Also if you run twins with headers like this be mindful of where your turbo exhaust out will go cause sometimes you will be limited with room and need to start cutting up your car pretty good to get them to fit. I chose the Hedman Shorty Headers for this very reason. I wanted the exhaust to exit past the K Frame and everything to fit under the hood without a Hood Scoop.

Plan,Plan and then Plan some more is the best advise. I had to change directions a few times with mine and it can get expensive real quick when that happens.