Date: Sat, 07 May 2005 17:27:58 GMT
From: "Dexter J" <>
Subject: Re: rrett t3 turbo

Salutations: On Sat, 07 May 2005 01:52:03 GMT, James Sweet <> wrote: > > "Dexter J" <> wrote in message > >> Salutations: >> >> On 6 May 2005 06:55:50 -0700, es <> wrote: >> > >> > OK i think i will go with the one i got right now and just 3" down >> > pipe. will it be better if i get the intake manfoled from the newer >> 2.3 >> > turbo saab 9000 engein. where can i get one of thoes and i have a M >> > boost controler right now what do u guys think i should run for psi im >> > at 14 right no. i heard it would be better if i run the fiul presher >> > regulater from a non turbo saab is that true. i just wont to have a >> > better topend on the car what is the best way to do this bcs the >> lowend >> > is really nice as is. later when i get the t28 in there it should be >> > really nice does enyone know where i can get a good t28 >> > >> > THANKS >> >> I'm not sure we are on the same lines here. >> >> Top end on a stock SAAB turbo is well and above *anything* you will ever >> likely use unless you live in a place that doesn't issue 'reckless >> endangerment' tickets or are retiring the machine to racing exclusively. >> >> If you are simply looking for more total boost - and you are not Trionic >> under the hood - get a manual boost controller and dial back when the >> waste gate opens. >> >> I believe your stock turbo is good for the better part of 19 or 20 psi. >> But - and this is very important - your engine management computer will >> cut off fuel when it senses the inevitable engine knock this will cause >> (the car will 'buck'). And let me assure you, the stock SAAB engine >> protection system (the chip) is very conservative in this regard.. >> >> > > I haven't checked on a Saab, but generally when it bucks like that, it > means > there's a simple overboost pressure switch which cuts off the fuel pump, > it's got nothing directly to do with knocking. Can't be good for the > engine > to hit that often either. On older C900 or 99T's - I think you might be correct, but don't actually remember. However, I'm pretty sure all 9000's cut out based on knock and/or resistance. It's tied into the Trionic system that adjusts for different fuels on later models. On pre-Trionic 9000, its tied directly to the knock sensor with feedback from the ignition coil (I think). It is all interpreted by the main engine computer in both cases. In my 1989CD model - the system was cutting out fuel because of a problem with the distributor. It would start arcing (missing) at higher RPM - which was interpreted as knock by the system, at which point it would start *violently* bucking. In my 1993 Aero - I'm sort of locked into base boost for the moment (cruise control problem we think), so I've not been able to run it into cut-out as yet. Perhaps next weekend if everything goes as hoped this week.. :) .. There are several interesting posts floating around regarding certain kinds of engine noise (timing chains - oil pumps) that can trigger a fuel cut out because of the internal block harmonics involved. Personally - I think it's a better (if more annoying and limiting) system overall. By interpreting sound and/or resistance - you can cut or adjust fuel rates for many reasons and much more quickly. 2,500RPM means that any lean or rich condition you are experiencing may be happening 41.6 times a second. Sound and electrical resistance is a better way to gauge this if you ask me. In a purely over boost based system - you can simply change out the switch to change the cut out. In the CPU governed system - you adjust all the parameters so as to allow for when the cut out happens. Same thing really - just different triggering sensors and greater latitude. The SAAB system allows for changes in fuel octane rates, altitude AND boost because it can adjust the ignition curve and fuel rates slightly depending on feedback from a couple of systems. Cut out is the last stop along the line. Works too - I honestly do get better mileage on higher octane fuel with Trionic than I do on pump regular, but I loose performance as I move down the pumps. The same was true of the 1989CD - except that it worked on mid-grade instead of high-test. If there is any serious complaint on my part, it is that the software controlling the Trionic 5 system is essentially closed source (no OBDII for us). Although, by Trionic 7, I think it is fully OBDII compliant. -- Radio Free Dexterdyne Top Tune o'be-do-da-day Bluegrass Boys - Rolling My Sweet Baby's Arms all tunes - no cookies no subscription no weather no ads no news no phone in no sign up required - all the Time

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