So what's a well sorted Bi-Turbo worth these days.

What's been done to it?

Hopefully a lot because stock they are a lot of trouble.
Properly modified they can be very nice but so many have been butchered into something else that probably doesn't work right.

Prices are all over the map and the cheap ones are hardly cheap of course.

You'll do better joining Yahoo Groups Biturbozentrum and discussing it over there.

 

Well.....1989 was the best, as all the bugs were sorted out by the factory (understressed larger motor, bigger brakes, wheels, 5 lugs, better Ranger diff, etc), and 1984 is one of the worst, as all the bugs were built in! My advice to all my friends is to find a 1989. If one can't find a 1989, then get a 1986-88 fuel injected 2.5l. And stay away from the carbureted ones, unless they have been gone through by an enthusiast and upgraded!

Prices imo:
Good 1989 : $11,000 - $15,000
Rough 1989: stay away
Good 1986-88 2.5l fuel injected: $8K-12K
Rough: stay away
Any carbureted biturbo: Upgraded in good shape: $6-9K
Any non-upgraded carbureted biturbo, regardless of condition: stay away unless you own a shop or are a do-it-yourselfer that can do the work yourself

 

Well said.

Wow. A 40 year BiTurbo.

That's scary in a number of ways!

Matt

 

Back to arithmetic class for you!

 

I think you're a bit optimistic on the valuations but since everything Maserati is jumping these days who knows for sure.

The hard part is finding any cars such as youv'e described.

I did see one or two very clean looking 84s (like new interiors) in the last year, remarkable actually, but there was zero to indicate that they'd had all the improvements made to them.

I disagree about the 2.8 motor, there's nothing to indicate that they've done all that much better over the years. 2L, 2.5L and 2.8L all have some issues. The 18V motor is easier and cheaper than the 24V motor to maintain IMHO. The problems usually appear due to poor maintenance. You just HAVE TO do the maintenance on these cars or you will be in trouble. That's what put them all into the salvage yards so soon. Only nuts like us who did our own service make it feasible to run these.

If you did the same to a 308 or a Lamborghini the results would be similar and were.

The 86 motor was the one that "stock" ran the poorest but you can change that.
The earlier cars had weak clutches which you can easily upgrade.
All of them use that same ZF 5 speed. It's not a joy of a of a box and once you start getting 275+ hp out of the engine you start overloading it. Heavier bearings fixes that.
All of them need intercoolers.
The 84 & 85 models need to be converted to water cooled turbos.

I upgraded my salisbury diff to the Torsen one, it's still not perfect but it's better.

The early brake calipers were superior but the later rotors were better. So here at least they never got that completely right. BMW stuff on the calipers.

So going from a well preserved 84/85 to a properly upgraded car involves a lot! But they are sweet once you get there. The later 89 and on cars save some of that and come with water cooled turbos power steering and an improved front suspension design and diff. They also have full leather interiors.

They all can use plenty of other improvements learned over the years just like any of the Italian cars discussed here.

Now here's one guy who did the ultimate upgrade of an early car and just bought a FI motor from MIE and did a ton to this car. I'm envious of some of the stuff but he did spend a lot of money doing it. Well worth the read.

Concours Motorsport Archive Projects, Tuning, Custom Fabrications | ARCHIVE

I know of another guy in the PNW who dropped a 2.8 24V motor in his 89 spider, not cheap.

 

Thirty! I meant thirty!

My mind's going. I really AM getting old.



Matt

 

I've got one I've had for nearly 29 years, that's scary enough!

 

This looks like a pretty clean 91 spider. It is an automatic but the 4 speed autos are pretty nice,

1991 Maserati Zagato Spyder | Mecum Auctions

$7K + buyers premium.

 

3500 GT...

Keep us informed if you purchase one.. There are several of us who own Biturbos...
I'm in the process of working out a couple of bugs on mine, as it sat for a bit...
These are good cars when maintained properly!! They can be a lot of fun to drive.

My Biturbo was the first Maserati I purchased and it spawned several Maserati GT
purchases..

Try to ignore the detracters and nay-sayers... Many have never owned one and
only repeat the negative comments they have read elsewhere...

Keep us informed...

Mike