[Sentientpuppet]

I just bought my first SAAB. An '87 900 8-valve and being that there is a turbo version I figure it wouldn't be to hard to turbocharge it right? If so what is recomended? Not something I'm interested any time soon but down the road I'd like to.

 

[trackside]

Hi there - this is a very frequent question and the answer is always the same -it's cheaper and easier to buy a turbo car in the firstplace.

 

[Si]

N/a to Turbo

I think there's quite alot of work involved, you may be able to LTP it but I'm not sure whether the n/a engines have the bits needed to fit the oil feed & drain pipes for the turbo.

If they do then you'd have to change the exhaust manifold, and all the inlet piping.

As I said if it's possible you'd prob be best LPT'ing it so you don't have to mess about changing the head/pistons etc due to the compression ratio's being different between n/a and turb engines, also not sure whether n/a retard the ignition timing like turbo engines do when you've 'GOT BOOST'.

Prob be easier to pick up a tubo engine and swap em over....or as Trackside said, buy a turbo car!:cheesy:

There's been a few posts about modding n/a cars so have a look at Perf, mods & tuning, if you do a search you should pick up a few tips.

Try searching for a posting called 'where's the love for n/a guy's' or something similar.

Is it a 8v FI or twin carb?

 

[Sentientpuppet]

FI... thanks for your help.

 

[gorper]

I just bought my first SAAB. An '87 900 8-valve and being that there is a turbo version I figure it wouldn't be to hard to turbocharge it right? If so what is recomended? Not something I'm interested any time soon but down the road I'd like to.

With some mechanical aptitude and willingness to learn about turbocharging, timing and fueling, it's pretty straightforward. Donor car is strongly recommended so you don't hunt around for little parts. Search here & other Saab-oriented websites/forums, but read with a critical eye: many write about this stuff but fewer have actually done it. When you're ready, Scanwest in Greenwood is an excellent resource for parts/advice.

 

[ejenner]

If you were thinking of starting with your existing block and rebuilding it with the intention of using it as a Turbo block then you'd be fine. The Turbo's have a different shaped piston which reduces the compression ratio to make the engine more suitable for running boost.

The two engines are actually different. The advantage you have over a normal turbo conversion is that they did make a turbo model so you can buy things like ECU's, turbos, pipes, ect, ect... and you wouldn't have to fabricate anything to make it all work.



It would be worth doing if the body shell was in really good order. But otherwise if you want a 900 with more power than the one you have go and buy a 16v turbo.

 

[gorper]

If you were thinking of starting with your existing block and rebuilding it with the intention of using it as a Turbo block then you'd be fine. The Turbo's have a different shaped piston which reduces the compression ratio to make the engine more suitable for running boost.

You can run stock c900T boost on a NA engine. The turbo cam also reduces compression ratio, BTW.

The two engines are actually different.

The only internal differences are the intake cam and the pistons.

The advantage you have over a normal turbo conversion is that they did make a turbo model so you can buy things like ECU's, turbos, pipes, ect, ect... and you wouldn't have to fabricate anything to make it all work.

Yes, and this is the beauty of adding a turbo to a non-turbo Saab 900.

It would be worth doing if the body shell was in really good order. But otherwise if you want a 900 with more power than the one you have go and buy a 16v turbo.

That depends. If you don't want the hassle of or are incapable of doing the conversion, then, yes, buy a Turbo. Otherwise, buy a donor car for a couple hundred dollars, convert your existing car, sell some of the donor's parts, and at least break even.

 

[Sentientpuppet]

thanks

Thanks for the info guys... and yes the body is in prime condition. same with the interior. I'm pretty happy with it. 150,000 miles and I only spent $250 on it at an auction so I'd say I got a really good deal. It looks like my grandmother was driving it! There is an recent oil service sticker in on the windshield. I did an oil change and complete tune up. All my inspections thus far the engine is in great condition. The only thing left is to replace some belts. I'll have to pick up a donor car maybe at the end of this summer. Thanks guys!

 

[ejenner]

You can run stock c900T boost on a NA engine.

Easy to 'say'... not easy or wise to 'do' :cheesy:

Melted pistons - here we come... :lol:


.

 

[gorper]

Easy to 'say'... not easy or wise to 'do' :cheesy:

Melted pistons - here we come... :lol:

.

Have you done it? If not, how would you know? People are running 10:1 at stock Turbo boost (~11 psi) or higher. There is a ~280 hp (dyno'd, at the *wheels*) car in mid-west U.S. on a stock 10:1 NA bottom end (pulled from a junker, no less). I know of an *11:1* B202 running over stock Turbo boost; been doing it for years, no APC. There are others on this board, on Saabnet, etc., who've done the turbo'd NA thing without problems. And there are many people out there in other marques putting turbos on NA engines who are also running 10:1 or thereabouts without problems (lots and lots of Civic owners, for example).

I have done the conversion on a B212, and run ~9.5:1 at ~11 psi (for now) with no APC; haven't killed it yet after 10k miles.

EDIT:

In addition to searching the forums:
http://www.pajjakid.com/ubipa/lpt_conversion.htm
http://beaudreau.50megs.com/SAAB/NATurbo.html

 

[Basre]

Perhaps..
but as with Penis size there are a LOT of claims that are not quite substantiated or even proveable
I've been fooling with Hondas since '88. less than with Saabs tho.. and 10 psi onna Stock Honda engine is more in the realm of hype than reality.. however there might be a few Hondas, anything is possible.. with seriously skilled attention.. that can sustain 10 psi with out decent boost and/or mixture controls.. reliably.. somehow... maybe... but I have yet to see one inna Flesh, and if i do.. I'll be on it like white on rice.. to paraphrase.

 

[ejenner]

On the second link his dyno figures only go as far as 132hp using a manual boost controller to by-pass the APC.

On the first link if he has done the things he has mentioned on the page then he has done everything except a re-build on the block. There are about 10 different fixes mentioned for the det / pre det problem and these include things like reducing the compression ratio to something close to stock by installing a modified 2.3 cylinder head and then also replacing the timing, boost control and fuel systems...!

If you want me to change what I said earlier then that's fine: "I will say you can do it but there's not much point. Saab went to the trouble of manafacturing the turbocharged cars with a lower compression ratio so the detonation, pre-det, knock and all those lovely things are kept down. Personally I don't think they went far enough as those problems still exist on the 900T. (in standard form when the temp goes up)"

Basically it's not good advice to insist that it's good to run boost on a high-compression engine. Better advice would be to suggest a project engine build with all the right bits in it to start with. Then just drop it in where the N/A lump was.

Water/ Propane injection: Using water, methanol, or propane injection will help reduce detonation and cool charge temperatures.

Another good mod for safely controlling boost for a 2.1L is to integrate a DI/APC system from a 91-93 9000.

Running high 93+ octane will allow you to run higher boost

A better downpipe will also help with removing back pressure which will allow the engine to run free'er and cooler

use a MSD universal BTM

and a quote from another website..

A B212 engine should be fun.
But you need to lower the compression to around 8.5:1.

Need to get a plate between two headgaskets or something...

 

[trackside]

No one is saying it can't be done - clearly with the right engine management controls added on it is possible but it's just not practical nor economical. Given equal budgets it's easier to go and buy a Turbo car in the first place or given equal time you are better off working those hours at your day job to pay for it.

 

[gorper]

The above opinions re: cost, difficulty, practicality, performance and unreliability run counter to actual experience. Those looking into the conversion will differentiate between hearsay/conjecture and experience/data. And draw their own conclusions. :cheesy:

Hint: If you fail to understand the problems--bolded by me, for your convenience--in the following quote, then DO NOT attempt the conversion!! :cheesy:

A B212 engine should be fun. But you need to lower the compression to around 8.5:1.

Need to get a plate between two headgaskets or something...

I posted the earlier links only for people looking for more info on the conversion. I'm sorry I wasn't clear. Ubipa's set-up used a stock ECU with no boost retard or APC. Beaudreau's dyno numbers aren't from a real dyno (read the page again, then search Saabnet for "road dyno"). Moot point, though (see examples I noted earlier)...




Fun thread but I'm done. Enjoy your Saab.

 

[gorper]

Perhaps..
I've been fooling with Hondas since '88. less than with Saabs tho.. and 10 psi onna Stock Honda engine is more in the realm of hype than reality.. however there might be a few Hondas, anything is possible.. with seriously skilled attention.. that can sustain 10 psi with out decent boost and/or mixture controls.. reliably.. somehow... maybe... but I have yet to see one inna Flesh, and if i do.. I'll be on it like white on rice.. to paraphrase.

(Well, I said I was done, but I just saw this lovely post and feel compelled to reply!:cheesy:

So if you've not seen one, then that must mean it's not true? Interesting logic. How many times have you turbocharged a Honda/Acura? How many times have you even *seen* such a car? There are plenty of them, dyno'd, on the internet. Yes, they have good timing/fuel, not stock (Hondata, the DIY Uberdata, etc.). And more than 10psi. Go search Honda turbo forums and see what you find.

Here's a fun thread, but before you clicky, remember, kids, the point of this link is to show that Hondas/Acuras can make big power with 10:1 and, sometimes, more than 10 psi (depends on turbo size, yes?). That's it, okay? Nothing more. Just that they can deal with 10:1. Okay, you can go there now to decide if this stuff is "hype" or "reality": http://honda-tech.com/zerothread?id=1263053

Want more action-packed linkage? :cheesy: Here you go...

If any of you know of the guy in California looking to make 500hp in his red c900 (see old Saabnet posts), you'll see why that isn't such a far-fetched goal here. Wait, before you go clicky, remember that the only point of this link is to demonstrate that a 500hp goal for a 4-banger, while extreme and more challenging for a Saab owner than a Honda (or even Chevy Cavalier) guy, is not outside the realm of possibility. That's it; nothing more: http://masetuning.com/case.html

Have fun!

 

[Leebo]

We just bot my father-in-law's 92 900NA Convert (yes, I begged him in '92 to buy the turbo).

We've got $600 in it so I'm not going to buy a turbo car, but would like to convert it. From what I'm reading the parts list includes:

Manifold
Turbo
Exhaust Manifold
Downpipe
IC and plumbing

Anything else I'd need?

I'd like to put together a parts list to buy used and bolt on. This would also be a great tech article.

There's no patience in my house for a donor car that's in the drive for months(the parts swap on a TR6 killed that possibility, though I found a 92 900t convert for $800 w/ blown tranny ;-).

BTW, here's an old link to the same topic:

http://www.saabcentral.com/forums/showthread.php?t=18522

 

[gorper]

You really ought to have access to a single donor car, but you do what you can, yes?

Ideally, you want a donor that has the same transmission type because of slight variations in the turbo water-cooling plumbing (the hardlines are different between ‘box types). And for your 92, for fueling purposes, ideally you want an 89 or newer donor (more below).


I am going to assume here that you want to run about the same amount of boost as a stock Turbo (~11PSI).



OK, In addition to Manifold, Turbo, Exhaust Manifold, Downpipe, IC, and plumbing...



Timing:

The NA car has a timing system (EZK) that allows max advance under light load conditions; it also does some retarding under load. But it’s not ideal for a turbo application. What I would do is install a Turbo distributor from an LH2.4 car (see more below) with an internally-mounted hall sensor; don’t use the existing crank-mounted hall sensor. (The signals from both types are the same.)



The Turbo distributor has a crude vacuum advance and boost retard system atop it. What you want to do is modify this capsule so that it will NOT advance under vacuum any more – the EZK will do this for you – but leave it so the boost retard still functions. This is achieved by removing the capsule from the distributor, then, take a small washer and grind a slot in it perpindicular to the edge and through to the center, then grind the edges of the washer so it will press-fit up under the base of the capsule. The thickness of the washer needs to be the exact distance between the base of the capsule and the notch in the “arm” that moves in/out under vac/boost. If this is not clear, get your hands on a capsule, put a pressure/vacuum pump on the line and see how it operates; once you do, it should make sense. In short, what you’re doing is keeping the arm from rising up by blocking it with the washer.



You will need to do a little rewiring: hack into the wiring to the crank-mount sensor so that you can run the wiring to the distributor. No big deal.



Fueling:

Your 92 runs Bosch LH2.4.2 Jetronic. You really want to use a Turbo ECU, which can appropriately add fuel under boost. Trouble is, no Turbo 900 came with LH2.4.2. You can either sleuth out a 9000 Turbo that ran LH2.4.2, or, because 2.4 and 2.4.2 use the same connectors and have *nearly* identical wiring (see your Bentley manual for the exceptions, which are mostly for the throttle switch), you can retro-fit a Turbo LH2.4 system. You’re going to need to do some homework here: a few plugs will need to be rewired/retro’d.



You will also want to use a Turbo throttle, which has the proper throttle switch you’ll need for LH2.4. (LH2.4.2 switch is incompatible with LH2.4 and LH2.4.2 throttle casting is different than LH2.4).



Note that you cannot use an LH2.2 system due to ECU plug incompatibilities.



Once you’ve sorted your ECU, you’ll want to run Turbo injectors. These are rated 21#/hr @ 2.5 bar vs. your existing 19#/hr @ 3 bar. However, because you’ll KEEP your existing stock 3 bar fuel pressure regulator, when at wide open throttle, you’ll actually be getting 23#/hr because the stock Turbo injectors are rated at 2.5 bar. With the increased fueling, your car will still get the same gas mileage (unless you spend a lot of time at WOT.)

Make sure your Turbo throttle switch is functioning properly (see Bentley).


Compression:

You can drop the dynamic compression ratio a little bit by using a Turbo intake cam, which has longer duration. The exhaust cams are the same on all c900s, turbo or not (exception: 1985 only). Your car runs a static CR of 10.1:1 vs. the Turbo's 9.0:1.



Exhaust:

You need to use a Turbo exhaust system (an entire cat-back stock system is fine, and inexpensive from eEuroparts). With your 92, the existing cat is the same as the Turbo cats, so you don’t need a new one. Don’t forget to grab a Turbo downpipe hanger from your junker' transmission. Also, I believe the Turbo has an muffler heatshield that the NAs don’t have; poke about for it.



While you’re at it, the stock cast-iron elbow off the turbo is quite restrictive; if you have some welding skills, it would be helpful to make your own elbow; either fab it such that it bolts right to the existing downpipe flange, or cut/weld it farther downstream, directly to the downpipe. You can do this with a couple 60mm (2.25") I.D. elbows.



Cooling:

The Turbo radiator has more rows than a non-turbo, IIRC. However, it may be that all later 900s have the same radiator. Check the p/n’s. You'll need the donor's lower radiator hose if the donor has a water-cooled turbo (88+).



Don’t forget to grab the plumbing beneath the intake manifold.



Oil Cooling:

You need the oil cooler and associated plumbing from the donor. Don’t forget the mounting piece at the block – it’s different than a non-turbo. Replace the lines if they look ratty.



Boost control:

Install the APC. It’s basically a stand-alone system (see your Bentley) and you can omit a few of its features (e.g., you don’t need to wire it to the brake pedal switch). If you are not going to use an APC, then I wouldn’t run more than 8-9psi with hi-octane (assuming you are using a Turbo distributor). You can see for yourself what the APC is doing by putting a 12V LED in the dash somewhere, (Pin 19 --> light --> ground). (When the APC detects knock, this pin is grounded.)



For the APC’s knock sensor, you take the stock sensor bolt out of the block, and find another bolt that is long enough to go through *two* sensors. Then, stack the sensors on top of each other, and torque them to the block (see Bentley for torque spec and special orientation information.)



Battery stuff:

I seem to recall there’s a difference between a Turbo and non-turbo positive battery cable, so grab it. Also, you’ll need the Turbo battery (it’s narrower), and the Turbo battery heatshield (do NOT run the car without it, as you will melt the battery.)


Misc. stuff:
While you're at it: take all of the a-arm shims from the donor, divide them into *equally thick* stacks, and add them to the 92. This will give you some negative camber, helping handling. If you can't get equally thick stacks, divide them up into equal *pairs* of stacks; of the pairs, put those that are *thicker* up front, and the thinner pair in back. Also replace both your outer and inner swaybar bushings with polyurethane, and lubricate them with anti-seize. The inner polys are available cheap at www.sasab.com, while the outers are available just about anywhere.


Good luck – it’s a fun project…

 

[GearHead]

the battery tips are redundant.If you make a custom downpipe,ie 3" or so you need to move the battery.You can move it out back in a marine battery box.or you can put it where the turbo IC is normally,then mount a FMIC across the front.