DI installation

[Kaas]

Have any of you guys installed DI on your cars? I have seen the guide on www.900aero.com but I cant seem to find a part no. on the DI box, can anyone help with that?

[Orca]

Here you go mate: 7484272

See David Fisher's excellent installation walkthrough over on UK SAABs:
http://www.uksaabs.co.uk/viewtopic.php?t=1529

[hansiu]

I've also been thinking about this, doesn't seem to be too much hassle, plus I allready have EZK igniton so I won't have to get a crank pos. sensor

Anyone else have any experience, would love to hear how the car runs afterwards, if there is any difference etc.?

[Saab-Daniel]

According to a mate of Kaas and I, the car runs much more smooth than before, providing boost faster and more cultivated engine performance.

Daniel.

[ejenner]

Originally Posted by hansiu

plus I allready have EZK igniton so I won't have to get a crank pos. sensor

Sorry to be the bearer of bad news but I do believe your EZK crank sensor uses a shutter-wheel which has only two teeth. The DI system uses an almost identical shutter-wheel except the DI one has 1 extra smaller slot which provides additional information about the position of the engine and not just the rate at which it is spinning as is the case with the EZK two-slot wheel. So three slots on the DI wheel, two slots on the EZK one. Also the pulley on the 900 for EZK and the pulley from the 9000 for DI have the screw holes in different places so you will need to adapt the DI shutter-wheel a bit so it will fit on the 900 pulley. or you could change to a 9000 pulleys and belts setup like David during his conversion.

[Saab-Daniel]

Anyone know where I can get an ezk shutter-wheel? Someone have a picture of it? Seems like something I could use triggering MS instead of the hall-sensor in the dizzy which failes sometimes... Also, could be fun setting up EDIS on a T8 maybe
Daniel.

[gorper]

Originally Posted by ejenner

...EZK crank sensor...shutter-wheel...has only two teeth. The DI system uses an almost identical shutter-wheel except the DI one has 1 extra smaller slot...

Yes, DI wheel has three slots. DI will not work with an EZK wheel.

[ejenner]

EZK wheels are pretty easy to get from the scrap yard as they are also fitted to non-DI 9000 EZK cars. A 900 wheel would be preferable as you wouldn't need to re-drill the mounting holes. The only problem with using the wheel from the 900 is that it has only two-slots so that won't let your ECU control sparks on individual cylinders because two slots won't enable your ECU to know the position of the engine. With two slots you need to keep the dissy to distribute the spark. It's still a good solution for controlling timing with an ECU but if you wanted to get fancy tweaking individual cylinders or setting up sequential injector firing then you need more teeth so the ECU knows the position of the engine. You could combine the signal from the two-tooth crank with a ref signial from the dissy but as you say - the dissy sensor isn't reliable so you'd be gearing up for failure if you went for that system. You could combine the two-tooth sensor with an additional cam sensor reading an additional wheel on the end of the cam-shaft but you'd have to add that on as an extra.


Here's a couple of pictures for you:




I think this picture shows the three tooth DI shutter wheel I got. It's not very good quality so it's difficult to see the teeth. It also shows the sensor attached to the oil pump cover. The reason I think it's the DI sensor is because I think I can see the small third tooth on the left side and it seems to be the 9000 crank pulley as well.




Here's a good picture showing one of my EZK shutter-wheels




Here's one which I tried to have modified. The workshop tried to weld some off-cuts from another shutter-wheel into the gaps to make a shutter-wheel without gaps so it could be re-cut with lots of new spaces in the right places. The problem however is the accuracy of the work means it's probably not round enough to reliabibly fit through the small gap on sensor. The other worry is what might happen if you spin a 12-tooth sensor at 6k rpm will the teeth start to react the forces and bend outwards as it spins round !?

[hansiu]

Originally Posted by ejenner

Sorry to be the bearer of bad news but I do believe your EZK crank sensor uses a shutter-wheel which has only two teeth. The DI system uses an almost identical shutter-wheel except the DI one has 1 extra smaller slot which provides additional information about the position of the engine and not just the rate at which it is spinning as is the case with the EZK two-slot wheel. So three slots on the DI wheel, two slots on the EZK one. Also the pulley on the 900 for EZK and the pulley from the 9000 for DI have the screw holes in different places so you will need to adapt the DI shutter-wheel a bit so it will fit on the 900 pulley. or you could change to a 9000 pulleys and belts setup like David during his conversion.

Yes I know, but the pulley on the 90-93 900 EZK has the same shutter-wheel mounting as the DI, so I can just switch out the shutter-wheel. And I won't have to buy the cranks sensor and oil pump lid...

[ejenner]

I don't think so. It must be the case that the any wheel on the 9000 would have different hole positions to any 900 wheel (I'd bet on that one) or that any 9000 DI wheel would be different to any other wheel (less likely)

I think any wheel from a 9000 will have to be re-drilled to fit a 900. Looking on widdies site it seems like you don't have to change it much as you can use one of the original holes and simply elongate the other two holes so it fits the 900 pulley.

[hansiu]

That might be, but elongating those holes shouldn't bee too difficult

[ejenner]

Actually I've just looked it up on the EPC and I can see the 9000 EZK shutter-wheel is the same as the 900 wheel although there are two different part numbers for that one.

Originally Posted by me

any 9000 DI wheel would be different to any other wheel (less likely)

This is the actual situation. The 900 and the 9000 use the same part for an EZK ignition system and a different part for the DI ignition system. Two part options listed for EZK and three part options listed for DI.

[hansiu]

I just read through the DI instrucions on 900aero.com and some of the things in the original version has been left out of the translation.

Heres a snippet translated from the swedish version:
"Pulley wheel, the easy way:
Get the pulley from a 90's EZK 900, I don't know the excact year they started using this model. These pulley wheel's have the same sort of hub as the 9000 DI model, wich mean that the DI shutter-wheel fits on without any mods.
So all you have to do is swap out the shutter-wheel!"

Of course I can't be sure my pulley is the right model since it's from 1990, but if it isn't il just have to mod it.

[ejenner]

They did change something in that area around that time although it was later than 1990. My engine is a 1990 and that still has the older style pulley and pulley bolt. I got a pulley and wheel from a 1993 which was different to my 1990 so my guess is that it came in with the 1991 revisions.

[Bennie]

Originally Posted by ejenner

or you could change to a 9000 pulleys and belts setup like David during his conversion.

Is the 9000 DI pulley and belts a bolt on, or need it some mod,s?

Cheers, Bennie

[ejenner]

It's not a straight swap. You have to move some of the pulley wheels back or forward. I've not done it myself but it has been done before. The details available aren't all that good so when I do the mod it will have to be a bit of the 'suck-it-and-see' type approach. The 9000 pulley is heavier than the 900 one but I don't suppose that makes any difference.

[hansiu]

ejenner, do you think it will be easier to swap the pulleys than to mod the ezk pulley?

[ejenner]

No. I think it would be easier to mod the DI wheel to fit the EZK pulley. That job only need a couple of holes drilling. Swapping the pulleys probably involves a bit of fabrication - not sure what needs to be changed but no doubt it would be easier to mod the shutter-wheel.

[Saab-Daniel]

I'll translate what needs using from the danish site later, as mentioned earlier, a mate has done the DI-conversion. He has put up a discription of what you need.

Daniel

[hansiu]

Originally Posted by Saab-Daniel

He has put up a discription of what you need.

Daniel

Do you have a link?