Attn: Saab C900 guys - power/driving experience question

So I'm finally starting to put some miles on my 89 900S (16v NA 5spd) and I'm increasingly aware of just how slow it feels. The factory rated it at 125hp, which isn't much I know, but it only has to lug around maybe 2800lbs. The engine revs freely up to the redline, so I don't think there's anything impeding it on either the intake (air and fuel) or exhaust (plugged cat) side, but I'm just not sure it's making the power it should. I haven't done a compression test, but the engine only has 102k miles on it, which is pretty low for these, and it's not showing any signs of excessive blowby or oil consumption, and makes good pressure. I'm sure it's lost some power from new, but the motor's not clapped out.

Power - what there is of it - seems to come on around 3000rpm. On smaller roads in the lower gears it's not bad as long as you keep the revs up. 1st and 2nd pull reasonably well, and 3rd is OK as long as you don't let the RPM drop too low. Momentum is your friend at these sorts of speeds, and as long as you drive that way you can move right along. The highway is a different story: getting to highway speeds takes time and revs (we're not talking 80s Mercedes diesel time, mind you, but it's not fast). For maintaining speed once you're there, the gearing doesn't help at all; we have a lot of fairly steep hills around here, and holding speed in 5th gear up a prolonged grade at ~65-70mph - even a relatively mild one - is not really feasible. And don't get me started on what happens to power when you flip the A/C on.

I know it's a vague question, but never having owned one of these before, does this sound roughly like what you'd expect in terms of power and driving experience? I'm just trying to get a sense of whether this is more or less how it's supposed to be, or if I should be looking for a problem.

It's been years since I had my 900 and it was a turbo. I remember it being pedestrian until the turbo kicked it. Also you have less horsepower than a Miata and 1/3 more weight. I think my Miata is pretty slow. 

It sounds about right for that car.  I had a 90 900S 4 door and it worked like you describe.  I am fairly sure that 5th gear in these cars is an overdrive, I know it was in my parents 83 900S, so hills will require 4th a lot of the time.

+1 on that sounding perfectly normal, our 900S was a fine car but couldn't hold a candle to my turbos.

OK, so it seems that's just the way it works. Fair enough. I purposely avoided the turbos simply because I was afraid of the additional stresses on the fragile 30-year old transmissions that seem to be (one of) the Achilles' Heel(s) of these cars. Given the power output from the NA motor, I'm confident that my transmission would be fine even if the innards are made of cheese. Plus, with rallyx figuring in to my future plans, I figured all that power through the fronts wheels wouldn't be terribly useful, and the compromise in cost, complexity, and reliability wouldn't be worth it. Perhaps I made the wrong choice - oh well. I'll learn how to get as much as I can out of it. Thanks, folks.

Don't be unwilling to downshift to 4th on the highway. Run it to the redline whenever necessary, or even when it isn't.

TurnerX19 said:

Don't be unwilling to downshift to 4th on the highway. Run it to the redline whenever necessary, or even when it isn't.

Oh, don't worry, I'm not afraid of the redline. I'm in the habit of hitting it at least once per drive in all of my cars, as long as the engine has time to get up to temp.

As far as shifting down to fourth on the highway, I'm not opposed to it, it's just a little different. My 128i has enough torque that downshifting is rarely necessary, even in sixth, and my 2002 only has four forward gears, none of them overdrive.

this was the one shining spot for the 2.1. It had closer to 140hp over your 125, but it was hardly as durable, tending to blow head gaskets from the thinness of the metal between the big bores.

In reply to mad_machine :

That's probably a nice useable bump in power, but also a pretty significant trade-off. I wonder if there are any little tweaks to the 16v 2.0 that might bump it up a few hp....

Bolt on a turbo? :-) The only differences between the N/A and Turbo B202 engines are the pistons (10:1 N/A vs. 9:1 Turbo) and intake cam.

https://www.saabcentral.com/forums/showthread.php?t=110394

How is the fuel filter ? Have you cleaned the mass air flow sensor ? I upgraded the coil helped on the felt power.

Alas, I shall not be bolting on a turbo.

Fuel filter hasn't been done, but the car is not falling on its face at higher RPM, so I don't think it's too bad. MAF is clean. Coil is what was there when I got it, so it might benefit from a swap, albeit marginally.

Whenever I end up pulling the intake and exhaust manifolds I'll see what the ports look like and match and clean them up if necessary. I don't know enough about real porting to go beyond that. I also wonder if I might see another horse or two by reworking the air intake to get some cold air in there.

I mounted the coil in a cooler area of the engine bay.

In reply to stan_d :

Good idea. That's an easy one to do.

depending on budget.. either go with carbs or after market fuel injection that you can tune?

I know the turbos you can go with the t5 injection system from the later GM900s. I wonder if it can be adapted to the naturally aspirated engines as well?

In reply to mad_machine :

I think if I were to go that far with it I'd be inclined to try Megasquirt over the factory version. I haven't read much about the T5 conversion, but it does seem to require a lot of changes to function. And I like carbs and know how to tune them - I've run dual 40DCOEs on my 2002 for decades - but I don't know that they'd be so easy to adapt to the Saab 16v. I'd probably have to scratch-build a manifold and linkage, and that's just for starters. Unless I found a set cheap they'd add significantly to the cost of the car and push me way over my self-imposed ~$2000 budget (which is mostly gone at this point).