Adding a Turbo to a 1993 Saab 900 S Convertible

Not so much what *you* didn't think of - it's the idiotic suggestion from your mechanic that's got me squirming. You can't just bolt on a turbo and ancillaries; the compression ratio needs to be lowered substantially too. Did you mechanic mention this or was he just blowing smoke up your arse?

Unfortunately I don't know what would happpen if you tried it anyway - maybe someone else here can say . . .

In the meantime, be wary of this mechanic.

BRgds, Robert

Same transmission, different exhaust.

Adding a turbo is a reasonably big job. In addition to all the bits you mentioned, there's the issue of compression. Non turbo models have higher compression ratios than turbo models. This means that you really need to swap the head when putting the turbo on.

To do the job properly would take a competent mechanic who knows Saabs maybe 20 hours. Add the cost of the parts, and you're talking a good chunk of money. Far more than the car's worth I suspect.

I thought the difference was in the pistons, not the head?

Dave

I'm betting the head would need changing. Although I'm not sure, it's fairly likely there are differences in cams and valve size and lift.

Kristian

I couldn't remember, so looked it up - the haynes gives the pistons as the same for turbo and non-turbo. I know for a fact that the head is different, it's possible that the pistons are also different.

Now this is useful traffic - I seem to remember it's the connecting rod and head are actually the business on that series 16 valve engine. The best bet I would think be to find a wrecked/rusted donor. You can refresh the engine and turbo on the stand - then drop it in with the correct electronics and gauges as you go along.

Maybe 10-14 paid hours if everything goes smoothly and you can refresh everything else supporting the turbo power on the way in. Clutch, tranny linkage and engine mounts.

Glad to see you survived the soup touraine brother Grunff.. :) ..

Hanyes gives the bore and stroke as the same on both turbo and non-turbo

- 9.0 and 9.3 respectively. The 8vs OTOH have a much bigger different -

That would be a good plan of attack, as long as the OP is doing it for love. If money is an issue, he'd be better off selling it and looking for a stock turbo IMHO.

LOL - I've been here all along. Sadly because of what we do we run several windows machines, but we're firewalled up to the eyeballs. But we also run several 'nix machines and even a Mac (don't get me started).

Ahh - 8 valve - of course.

Was pretty sure it's the rods and the head whilst the pistons are in fact the same between turbo and non-turbo units on both series engines.

As to OT Sasser fix thread - I realized once I posted it that I had compromised my little patch of tranquil escape. Still, all hands to stations when the Bonapartes hove into range eh?

Cheers and best wishes - all nighter here I'm afraid.

If the wrist pin is lower in the turbo piston, as I seem to recall it is, that affects compression but not bore and stroke. It also allows compression change without using a different head or crank or rods. When I helped a friend rebuild his 99 Turbo, I thought the difference was in the pistons, but that was (a) over a decade ago, and (b) the B engine rather than the much later engine in the 1993 16V configuration.

Yup, a donor car is the way to go here, that way you get all the important bits.

Dave hinz