Interesting observation on SAAB V6 Turbo

Contour Enthusiasts Group Archives

I was looking over our NOVANTA concept car out back which uses the standard 9-3 V6 Turbo driveline, and took a close look at the turbo system on it.

The crafty Swedes are running a single turbo, somewhere in the neighborhood of a T-25 or thereabouts off SOLELY the front bank. The exhaust from the turbine then rejoins the rear bank via a y-pipe after it passes under the seam of the oil pan and engine.

So if you wanted a little boost (low pressure ~5-6psi) in performance you could almost try using a set of headers and run a T-25 of the front one and do the same setup on a Contour.

omder:

I suppose low boost would be ok but I would be concerned with an imbalance in the exhaust flow of the engine banks.

Originally posted by warmonger:
I suppose low boost would be ok but I would be concerned with an imbalance in the exhaust flow of the engine banks.

Good luck building a fuel program to run different trims to each bank.

The OEM's could spend days and weeks perfecting their complete tune. They have that luxury.

Would the fuel trims really need to be different for each bank? I would think the ideal operating for every cyclinder, seeing as they would all be seeing boost, is the same, although I do realise that the pressure variation across the bank would be different as the turbo is a restriction to the side it is mounted on.

This is nothing new. Saab has been doing this on the v6 turbo's for many, many years.

I've heard that a v6 engine would need to be twin turbo charged to be CARB legal so maybe running off only one bank makes it CARB legal and it is also cheaper than the twin turbo setup.

Originally posted by Blackcoog:
I've heard that a v6 engine would need to be twin turbo charged to be CARB legal .......

That's sounds like BS to me.

Originally posted by Blackcoog:
I've heard that a v6 engine would need to be twin turbo charged to be CARB legal so maybe running off only one bank makes it CARB legal and it is also cheaper than the twin turbo setup.

Only for an aftermarket setup. OEMs can make virtually any configuration CARB legal for a new car, provided they meet the emissions standards. For aftermarket conversions, CARB is ultra strict about what may be moved and where. Only a very specific package of twin turbochargers would even have a remote shot at getting a CARB EO number. And unfortunately, that sort of package in a contour wouldn't have a prayer of fitting in anything resembling stock.