Date: Sat, 03 Oct 1998 20:58:35 -0700 From: Justin VanAbrahams <jvanabranopsamnet> Subject: Re: Allowable boost 85 900T
Baur323 wrote: > > I just installled an aftermarket turbo (Stage 1 from Group 6) in my 85 900T and > was wondering what the recommended boost is on a 211K mile motor. I'm hitting > 8lbs now and was wondering how much father I can go without blowing the motor > up. No mods to motor, yet. I want this motor to be reliable, as this car is > my daily driver until I transplant a tuned motor into the car. Thanks > > -ray Please don't take this the wrong way, but it probably would have been advisible to go over the motor before investing $$$ in a new Turbo....Unless of course your turbo was already shot, in which case why the heck not... :) The stock turbo on a 900T is good for 18 or so psi before it starts losing efficiency. I know people running upwards of 20 psi, but this is crossing the point of diminishing returns. On an old engine, the best thing you can do is have it professionally rebuilt, or find a lower-mileage motor from a wreck to start out with. Aside from that, you'll find on Saab 900s that generally the weak link is not the engine, but the transmission. More boost means a sooner rebuild - the 5-speed in a 900 is not its best aspect - and over-stressing an already weak tranny WILL lead to a rapid rebuild. My '88 SPG had it's first tranny rebuild at 75k after the previous owner bumped boost from 11psi to 16psi. Keep this in mind. If you really wanna make your Saab go faster, come visit my website sometime next week - I haven't had a chance to upload the new pages yet... http://www.bfp.net/saabweb -Justin