saabhippo

2010-08-05T22:50:00.000-07:00

This is a test.

Weight, weight, don't tell me...

2006-10-16T14:39:00.000-07:00

Some c900 part weights:

Sunroof (excluding motor): 39 pounds
Hood: 59 pounds
Rear hatch (including glass): 64

Parts weighed with a postal scale, so those numbers should be within a pound or two.

"The things you think are useless I can't understand"

2006-09-27T20:06:00.000-07:00

Or so said Donald Fagen. Of course, he wasn't talking about a car. But, here, I am. What we've got here is a pretty darn nice 92 900S. I bought it at an auction knowing it had a bad headgasket, but not that it had a bad transmission, too. It was totalled by the prior owner's insurance company so if I got it back up and running, it'd still have a salvage title.

96,525 miles is all she's got on the clock. (The last mile wasn't actually driven: I ran her on jack-stands to be sure the odometer was working.)

So off to the crusher she goes. But not before I part her out...

Thought you knew c900 injector flow rates? Me, too...

2006-09-20T20:59:00.000-07:00

I recently took for granted some data about cam timing and newgen heads; I found out that the info was wrong. For years, I've accepted the oft-cited injector delivery rates of 21 lb/hr for Turbos, 19 lb/hr for non-turbos. Wrong again.

From the Saab technical manual (conversions are mine -- divide cc/min by 10.5):

16V Turbo (2.5 bar reg.): 208 cc/min (19.81 lb/hr)
16V Turbo (2.8 bar reg.): 220 cc/min (20.95 lb/hr)
16V NA (B202i or B212, both 3.0 bar reg): 180 cc/min (17.14 lb/hr)
16V Lucas (3.0 bar reg.): 290 cc/min (26.62 lb/hr)

Incidentally, I found some data on the 24 lb/hr light blue Ford injectors (Bosch 0 280 150 947) that people use. Actual testing on a bench found these to flow 25.33 lb/hr @ 3.0 bar fuel pressure. (Flow measured by an injector cleaning/testing company.) I also found some data as quoted from a Bosch manual: 0280150913/947... rating is "255.9 cc/min @270kPa", or 24.37 lb at 2.7 bar. Converting this spec to 3 bar yields 25.68 lb/hr.

B204 head on B2x2 cam timing

2006-09-19T22:17:00.000-07:00

You have read my forum posts about putting a B204i head (sometimes referred to as a T5 head)* on a B2x2 block. I’ve written about the cam timing change due to the head being thinner, and how it comes to 10 crankshaft degrees.

I was apparently wrong.

A well-respected person on a forum noted that the thinner NG head retards cam timing by 10 crankshaft degrees. I decided to do the math myself, and found him to be mistaken. Here’s the equation, from a book on engine performance:

D = 720h/NP

where
D = amount of retard (crankshaft degrees)
h = change in cyl head height (1mm or 0.0394") [source: Saab manuals. Basically, the NG and OG heads differ by a millimeter]
N = number of cam sprocket teeth (mine's 38 teeth) [source: me – I counted ]
P = chain pitch (mine's 9.525mm or 3/8") [source: Saab OEM chain company in Germany]

So running the numbers : 720*1mm/38*9.525mm = 1.989 degrees of retard at the crank, not 10.

I posted this information at an engine-building web forum for professional builders and got confirmation that it’s correct from two people using two different methods:

Quote:

--Since the slack side tensioner will take up the slop, the cam will retard 1 mm at the pitch circle circumference.
--The circumference is 0.375" or 9.525 mm x 38 teeth = 361.95 mm.
--Thus, 1 mm cam rotation = 1/361.95 of 360° or 0.9946 cam degrees = 1.99 crank degrees.

Quote:

I laid it out in SolidWorks(Hey, it's pretty close to the end of the day ! ), and got the same .9934 cam degrees, or 1.987 crank°.

Anyway, the moral of the story is this: DON’T BELIEVE WHAT YOU READ. EVER. Not even from people whom you believe to be knowledgeable, experienced, whatever. They can be mistaken, flat out wrong, etc.

*Calling it a “T5 head” isn’t exactly accurate, because these heads were fitted to many non-turbo engines that were controlled by Motronic!

B204i head on B212 block

2006-09-17T21:33:00.000-07:00

I put a 96 newgen head on a B201 block that I had bored to fit B212 pistons. The ports flow better, and the intake valves are 1mm larger than B2x2 intake valves. My head has had some minor port work done, too.

Couple things:

The newgen head is THINNER than the B2x2 heads; this retards cam timing 2 crankshaft degrees -- if you cannot tolerate two degrees, then you need to run cams from a newgen head, not a B2x2 head. Because you need a slotted exhaust cam to run your distributor, this means your exhaust cam needs to come from a non-turbo newgen 900 that ran Motronic (mid-90s).
Use B2x2 cam gears. Use a B2x2 coolant temp sensor (at the front of the head).
I neglected to measure combustion chamber volume. On the web, one poster says it's 50 cc's and another says it's 44.8. YOU SHOULD MEASURE IT and are an IDIOT if you don't and put a head on to find it doesn't work right (this, coming from an idiot who didn't CC the head first).
The B202 intake supposedly does not fit without modification. I was able to get a B212 intake manifold to bolt on without modification; however, the port matching is VERY close, and my machinist asked that I do everything possible to mount the manifold as high as possible with respect to the head. After 20k miles, it works perfectly.
The head can be modified WITHOUT welding: your machinist needs to mill out a space to fit a plate of aluminum to bridge the space between firewall-end timing cover bolt holes. The plate is epoxied in.
For power steering, see pics below. For AC, you're on your own, but could do something similar to the PS bracket I fab'd.
For a good online calculator, see the excellent not2fast website.
This is an INCOMPLETE LIST of details. YOU are responsible for making your own head swap work; reliance on a some online "recipe" from some anonymous source (that'd be moi) is folly.
When I have some time, I'll try to add more details. In the meantime, here are some pics (the first one I found on the intarweb, the rest are my engine)...

Here's the gap at the timing cover:

Here's the customized motor mount bracket:

A shot of the PS bracket, as well as the cover-to-head area post-modification:

Another shot of the bracket:
Hey, why not another pic of the bracket?

Free bandwidth. Weeeee....
Uno mas...

Original Factory Intercooler

2006-08-12T22:50:00.000-07:00

I autocross with a guy who's got access to all sorts of cool old Saab racecar parts. Including this factory intercooler. Note the endtanks -- no stock down-and-back path like the stock intercooler. I guess the down-and-back path was more efficient?? Interesting...

B2x2 Gasket Crush: 0.052-inch

2006-07-12T22:05:00.000-07:00

Took out the caliper and measured an old headgasket. The gasket crush on this gasket is 0.052-inch. This is an average of 12 measurements (4 on each hole); thickest measurement was 0.053-inch; thinnest was 0.0515-inch.

I also measured a new gasket. Not that it's important, but I got 0.054 to 0.056-inch...

So now you know.

4-Speeds are so cool...aren't they?

2006-07-12T18:51:00.000-07:00

There's lots of talk on the intarweb about how cool it'd be to have a 4-speed transmission from a 99 or early 900. Well I got one and there's some things to know about them before dashing out to Walmart to pick one up.

There aren't many around, so you'll have to go hunting for one.
Most of the gear clusters, I'm told, are split at the gear roots. So just because you find a 'box doesn't mean the cluster is usable for power. Good luck.
The only ones to have are the later, chain-driven versions (77+?? 78+??). The gear-driven 'boxes aren't worth crap on a 900.
The best ones are said to be "chill cast," whatever the hell that means. To me, it doesn't mean much because this info is on the intarweb only, so until someone produces some Saab documentation, it's just a rumor. That said, mine happens to be the same p/n as the purported "chill cast" boxes. I feel special. Really. Actually, not really.
You're going to lose your oil filler: the 4-speed has a narrow dipstick tube because the oil was added through the valve cover back then. You'll either have to suffer through adding oil through this tube, welding on a newer, 5-speed dipstick tube fitting, or fit a filler cap to your valve cover. I used a customized filler made of plastic from a Subaru. You can also get a generic filler cap from Summit Racing, etc. and weld it on. Or cut one off of some other car's valve cover.
Your turbo bracket won't fit -- you'll need to notch it a little to clear a rib on the 'box. Nothing major, though.
Your 900 downpipe bracket won't fit, either. You'll either need to fab a new one or get one from a 4-speed Turbo.
Your gearing is going to suck on the highway: these 'boxes are geared short, and you'll be turning around 3 grand at 60 mph. If you live where the speed limit is 70, then you'll be closing in on 4k RPM when keeping up with fast (75+) highway traffic. For a daily driver with a highway commute, a 4-speed is, frankly, silly.
The pinion bearing problem is still a problem. It's just the gears that are stronger.
The 4-speed cases are heavier than 5-speed cases, in part, due to a different alloy. There is less magnesium in them. (I am told that the newer, 5-speed cases are more brittle, in part, because of a higher magnesium content in the alloy).

Bumper Weights: Old vs. New

2006-07-02T22:53:00.000-07:00

Saabcentral's History of the 900 page states that the '87+ bumpers are 33% lighter than the -'86 bumpers. The source of this information is uncited, so I weighed rear '86 and '89 bumpers today and found them to weigh approximately 22 and 15 pounds, respectively, which does work out to about 1/3 lighter.

So for owners of -'86 cars looking to shave their car's weight, updating the bumpers will net you a 14 pound drop (assuming the front bumpers also weigh 22 and 15).

At the Pull-a-part, I noticed the early 80s cars had a different sound proofing material. Next time I get the chance, I'll weigh the old black version and the newer grey style...

DIY Poly Lower A-arm Bushings

2006-06-13T10:41:00.000-07:00

I made my own lower bushings out of aftermarket polyurethane c900 swaybar end bushings using a Dremel tool. I cut off the solid end and ground them so they were symmetrical on both ends, like the stock bushing.

They were a PITA to install (using a press at a repair shop), and, performance-wise, I can't tell the difference between them and stock.

The upper bushings are thin, so the amount of deflection during cornering isn't going to be that much, and isn't going to make any difference unless you are trying to get the last bit of handling out of the car. On the street, or on the track with street tires, I'll wager it'll make about...0% difference in grip.

It goes without saying that, without a serious custom alignment, stiffer bushings are a complete and utter waste.

If you're looking for better steering response, add some toe out to the front end, and maybe try polyurethane bushings in the steering rack.

The likely reason for the high cost of aftermarket poly is low demand; the buying public also believes it's the greatest stuff since sliced bread. You could have custom brass, nylon, Teflon, or UHMW bushings machined for less $$.

9000 Brake "Upgrade"

2006-06-12T22:05:00.000-07:00

Some facts:

9000 calipers are 3.6 pounds heavier per corner -- that is, caliper and rotor. (This can vary a bit depending on which rotors you have.) This is all unsprung weight.
9000 calipers and Aero/Super Aero rims add 43 pounds to your car, all of it unsprung and a lot of it rotating mass.
The heaviest 9000 rotors, by Balo and Brembo, weigh 14.95 and 14.88 pounds respectively; meanwhile, the lightest rotors, by Zimmerman, weigh 14.5 (their kick-ass cross-drilled rotors weigh 14.0 pounds). The heaviest 900 rotors, by Brembo (which is OEM, I believe), weigh 14.2 pounds, whereas the lightest, by ATE, weigh 13.44 pounds.
The stock donut spare tire does not fit over 9000 brakes: if you get a flat up front, you'll have to swap a good rim from the rear to the front, then put the donut on the rear.
Installing 9000 calipers requires an adjustment to the master cylinder to compensate for the longer pedal travel. This travel is due to the larger piston size in the 9000.
Installing 9000 calipers and rotors requires the use of washers on the caliper bolts; without them, the bolts will rub against the rotors. (900 rotors are 278mm x 23.5mm thick, while 9000 rotors are 280 x 25mm thick. If you purchased "9000" rotors that are 23.5mm thick, then you were sold 900 rotors being sold as 9000 rotors.)

Brakes

2005-08-02T19:38:00.000-07:00

Big brake kits, cross-drilled and slotted rotors, and stainless steel brakelines are quite popular these days. But does your car need them? Are they worth the money? Will they stop you faster?

Make an informed decision about brakes and brake components by perusing the following links to various articles by automotive engineers and brake manufacturers.

Start with this article by automotive engineer James Walker, Jr. This one [8-page pdf], also by Walker, is similar, but not written in a journalistic tone. Next, read a similar article co-authored by race car engineer and legend, Carroll Smith.

To learn more about slotted and cross-drilled rotors, read what Walker has to say in an article on rotors. Also read StopTech's recommendations, as well as Baer's, paying particular attention to their recommendation for cars seeing track duty. Finally, read this entertaining, if somewhat mean-spirited forum thread.

StopTech has a good FAQ and Technical section for further reading on various brake-related topics.

"What about performance claims by brake companies who sell cross-drilled and slotted rotors," you ask? Well, whether you believe them is up to you, but if you've read the links, then you probably don't.

"What about Porsches and Corvettes? They have cross-drilled rotors." Well, yes, they do, but not on their race cars. Porsche and Corvette are in the business of selling cars and cross-drilled rotors help them do that.

"What about race cars? They use cross-drilled rotors." Almost no race cars run cross-drilled rotors. Exceptions are very light, low-powered formula cars, which don't require the thermal mass of a full rotor and can benefit from the lightening. But these are open-wheeled single-seaters weighing a fraction of a street car.

Like buttered toast

2005-08-02T18:11:00.000-07:00

Remember, kids, a Saab is like buttered toast: If you drop buttered toast, hope that it lands butter-side up. If you drop a Saab, hope that it lands roof-side up.

Why?

2005-08-02T15:35:00.000-07:00

Because facts and proof taste better than hearsay and conjecture.