2.1 Turbo

[Saab6]

With all this thinking of adding a turbo motor into my 92' 900S it has me thinking of turbo charging the 2.1L. I've done some reading and research and I would appreciate some input.

From what I've read the number one issue when turbo charging an NA engine is the fact that a NA engine has a much higher compression ratio so this would mean I could only run low boast. I've read 4-5lbs is a good starting pt which could be achieved with a MBC. (or just base boost)

If I were to get all the hardware from a Turbo car could it be easily implemented into my car? I would the turbo, intercooler, exhaust manifold, piping and lines for the oil/water injection. Could I run an MBC set at around 5lbs and eliminate using an APC controlled waste gate?

The second concern is detonation and engine knock. I'm pretty sure EZK had some kind of knock sensing protecting. Would it be possible to leave the factory set up and wire up a knock LED to learn my limits? Where would the pin be for knock on EZK?

I know timing and idle would have to be adjusted accordingly after a conversion and I would have to run a higher octane fuel.

With around 5lbs of boost on a 2.1 how much hp would the be equivalent to?

If I were to shop around for turbo's which would be more suitable the T3 or TE-05? I know the mitsu spools up faster but I would never be running it close to full boast.

What am I overlooking? I see there are some threads on here but nothing in great detail especially in regards to the 2.1 with EZK.



I’m not even sure how this would work. I don’t even know if it’s possible but I’ve seen it done on here before and the principles are pretty basic. It seems like it would be worth the trouble and even quite simple in comparison to an engine swap.

Thanks a lot in advance. When will my ideas end?

[woywitka]

Seriously, it is easier and more proper to just buy a turbo car. For all that time/effort/money buy a nice Aero/SPG and develop that car!-PLus you have an actual "turbo" and it could become collectable and such one day possibly.

My input anywho.

[Matt88S]

Not worth it, easier, cheaper, better to sell the car and buy a turbo model.

Sorry, but somebody had to say it, I'll play scrooge for today.

Even the few who have managed to do it often still run into driveablity issues and the perfermance increase is not going to be worth it IMO, even full turbo Saabs are only 165-175, not exactly rip roaring power machines. You would probably be around 150-155.

I'm pretty sure EZK had some kind of knock sensing protecting.

Absolutly, however it has nothing to do with a turbo system or coping with knock caused by a turbo system, ie its going to do everything in its power to stop the knock but all to no advail as it has no way to reduce the boost. The turbo and N/A engine control systems are quite different, the N/A being better but different, although you could wire in a knock LED thats a rather jury rigged way to control overboosting even with a MBC as backup.

Performance wise even if you buy a full pressure turbo model with 175 hp you are pretty much stuck there, you can mod it some but the gearboxes cannot take over 200 reliably, (read as periodic catastrophic failure).

For all the time and money you would put into doing this you could either a, buy a FPT Saab with more power stock that a modded N/A could ever have, or b, put it into another car and end up with a pretty fast vehicle, preferably a vehicle with a trans that can take it.

If you just love saabs but want more power get a FPT model. The beauty of the APC system is you can get max power all the time without ever having to worry about damaging the car. Its all taken care of for you. To me thats better than having to watch gauges and lights and hope nothing goes pop!

Cam is different too.

[woywitka]

Originally Posted by Matt88S

I'll play scrooge for today.

.

yeah blame this guy instead

Seriously again, hard to let a Saab go, but you won't regret just saving up good money and buying a truly nice 900. A real minter can be had for just $5,000, or start with a cracked dash, torn headliner special for $500.

[Saab6]

Thanks for the input.

I'm new to turbo idealology..
How is it possible to overboast if an mbc is being used? I know a 900T can run without using an APC of base boost, and I haven't seen anyone overboost.

So it's possible it sounds like a head ache. But it seems pretty simple if you have acesses to used parts and some time.

[SteveTheFolkie]

I wonder ... as the main issue with forced induction on an NA engine is detonation - what if one were to run ethanol - not gasahol or some E85 blend - but straight 190+ proof ethanol. An NA engine can run 14:1 compression on straight alky (I know, I've built 300CI straight 6 chevy engine (that produced around 500 HP) for a friends stock car years ago) - so if we're at 9.5 or 10:1 it'd seem we could run considerable boost + the higher compression ratio (if we could double the fuel flow, as required by alky) and destroy gearboxes in darned short order !

Of course, you do want this for the street I suppose .... but it'd be fun while it lasted!

[Si]

Another problem with be the EZK thingamagig, with a distributer you can just swap to a turbo one with a vac capsul so timing can be adjusted depending on boost pressure, where as with yours there is no way to tell the ignition system you are 'on boost'.

[philb]

Yep, pretty sure the ezk cannot react fast enough. The turbo system would work, but is crude. To maximise your gains, you might be better off going standalone. ( megasquirt )

[Jim Mesthene]

Originally Posted by philb

Yep, pretty sure the ezk cannot react fast enough. )

The computer is too slow?
The EZK reacts so fast that it adjusts each individual cylinder's timing based on its performance on the last spark.
If I recall, EZK advances each cylinder 1/2 degree each spark until it detects detonation; then it retards that one cylinder 2 1/2 degrees. The process gets repeated at every firing stroke for each cylinder individually; at any rpm. It can compensate for a hot spot in one combustion chamber without disturbing the other cylinders.
Unfortunately, EZK can only adjust spark. If the cause of detonation is too much boost, EZK can't deal with that. That's why you'll only find EZK on N/A cars.
A few years later, SAAB introduced Trionic in the 9000 series. Trionic integrates APC and EZK to control detonation even more precisely.

[Matt88S]

Originally Posted by Jim Mesthene

The computer is too slow?
The EZK reacts so fast that it adjusts each individual cylinder's timing based on its performance on the last spark.
If I recall, EZK advances each cylinder 1/2 degree each spark until it detects detonation; then it retards that one cylinder 2 1/2 degrees. The process gets repeated at every firing stroke for each cylinder individually; at any rpm. It can compensate for a hot spot in one combustion chamber without disturbing the other cylinders.
Unfortunately, EZK can only adjust spark. If the cause of detonation is too much boost, EZK can't deal with that. That's why you'll only find EZK on N/A cars.
A few years later, SAAB introduced Trionic in the 9000 series. Trionic integrates APC and EZK to control detonation even more precisely.

Yup yup, what Jim said.

Absolutly, however it has nothing to do with a turbo system or coping with knock caused by a turbo system, ie its going to do everything in its power to stop the knock but all to no advail as it has no way to reduce the boost. The turbo and N/A engine control systems are quite different, the N/A being better but different,

[TheRedBaron]

Megasquirt could handle the spark, fuel and boost but I'm not sure if it has knock detection. Might be worth looking into, especially if you have a laptop to fine tune it on...then you wouldn't have to swap the apc or ecu stuff...

[912 fanatic]

if you put a turbo on a non turbo block where do you put the oil return from the turbo.

stephen

[Jared S]

I've turboed my 2.1 litre with great results. Check out my website and feel free to ask me anymore questions you might have.

[gorper]

Search my old posts.

[Saab-Daniel]

The EZK-system has 1 (one) knock-sensor, so it can't adjust the ignition individually. Also, it dosn't measure the anything over the plugs, as the plugs are the excact same as you use on a normal N/A 16v. On the DI-cars you get ion-sensing and individual ignition-control, not on a c900 (unless you adapt a DI-system to the car).
If you want to convert your 2.1 til a turbo, you could do it, just because it's a project, that's reason enough for me. But it really depends on what you want out of the car. You definetly need the Fuel-system from a Turbo, otherwise you will be running lean = no good = BOOOM. If the ignition-system is up to the task, I don't know, but I would at least change to Turbo sparkplugs if I where to use the old system.
Daniel.

[Si]

If there is already a trigger wheel fitted would the DI + APC route be best? Even just running it with the solenoid valve unplugged so it just runs at base boost, that way you get the benefit of the later ignition control & knock detection, and it would be reletively easy to set-up, well in the grand scheme of things.

[philb]

Originally Posted by Jim Mesthene

The computer is too slow?
The EZK reacts so fast that it adjusts each individual cylinder's timing based on its performance on the last spark.
If I recall, EZK advances each cylinder 1/2 degree each spark until it detects detonation; then it retards that one cylinder 2 1/2 degrees. The process gets repeated at every firing stroke for each cylinder individually; at any rpm. It can compensate for a hot spot in one combustion chamber without disturbing the other cylinders.
Unfortunately, EZK can only adjust spark. If the cause of detonation is too much boost, EZK can't deal with that. That's why you'll only find EZK on N/A cars.
A few years later, SAAB introduced Trionic in the 9000 series. Trionic integrates APC and EZK to control detonation even more precisely.

Yeah, but when boost comes in, it needs to retard maybe 4 - 6 degrees quickly. If it could do that, surely saab would have fitted to turbo cars? The apc can do the job of pulling the boost back. If the ezk can work on turbo cars, presumably it would be a good mod to just go and fit it.

[Saab-Daniel]

Philb: It dosn't really have to do that, the vacum-capsule does it on a standard-system, but it's really crude adjustment. Adjusting it gradually is way better for performance...
Which is why mapable ignition is so desireable
Daniel.