: Centrifugal Superchargers

12-04-05, 01:26 PM
Does anyone know anything on centrifugal superchargers, like how much power would they add to the catera.

12-04-05, 09:41 PM
1st. Nobody makes a supercharger specifically to fit a L81 engine. Although rumours from europe say the police pursuit Opel/Vaxhaul's had twin turbo's.
2nd, added HP is closely related to change in input pressure. Normal i/p is 14 psi (atmosphere) if the s/c adds 7 psi boost, that would add about 50% hp.
3rd. The engine won't handle much boost because it's got a high compression engine. 10:1.
4th. You'd have to beef up the mains, crank, and change connecting rods. to reduce compression ratio and handle the downforces. May as well change the valve stems too while you're at it with ones that have drilled oil passages and are made of stronger metal than stock.
Are you discouraged yet? It'd be cheaper to drop in a CTS 3.6 litre w/control module/xmission from a salvage yard. Good Luck!
Anyone out there know differently, I'd love ta hear what ya got to say!

12-05-05, 07:54 AM
IT has been done though, by Steinmetz and a few rare cars have the system in europe mainly:


12-05-05, 04:42 PM
Once again, I feel the Pavlov effect kicking in. Mouth watering , tail wagging. But I'd be happy to hear about someone who has tackled the dual turbo issue. Anyone out there done this? Oh ya! I'm too cheap to invest 8 large in a car. I'm a firm believer that if you want something screwed with, ya may as well be one doing the screwin'.:wacky: :wacky: :wacky:

12-05-05, 06:53 PM
I'm just curious on the supercharger for the catera/cts/elldorado/allante off ebay. If anyone has used one.

12-13-05, 11:11 PM
They did make a Saab 9.3 with a supercharged L81 engine with a 2.5 litre displacement, but it was a limp lizzard. It had a set-up to give better torque at lower rpm. Which makes sense as it wouldn't handle 10:1 compression ration. But the rated horsepower of that engine was still only 200. I haven't heard of anyone trying to adapt the supercharge to the Catera. You'd have to reduce the compression. And that means putting in shorted connecting rods. And would you end up with only 200 hp? Theoretically you should be able to boost output to 350 or 400 HP. But that would require lots of internal engine re-work. I have no idea of the spec's on the Saab supercharger. I can't find any reference to the aformentioned supercharger on ebay. Can you fill me in?

07-18-06, 09:49 PM
They did make a Saab 9.3 with a supercharged L81 engine with a 2.5 litre displacement :confused: uhhh... BS? L81 is 181 cu in, which is 3.0. Supercharged Saab? That's new to me...:lies:

07-19-06, 09:37 AM
:confused: uhhh... BS? L81 is 181 cu in, which is 3.0. Supercharged Saab? That's new to me...:lies:

It's true, but it wasnt supercharged - it was turbocharged in FWD setup. And how they had it tuned, it had the same HP but about 240 ft/lbs of torque. There were slight differences internally, the rods were stronger and had better oiling etc.

And it was the Saab 9-5 3.0t from the 90's-2000 something..

07-20-06, 04:50 PM
R-(u ever)Caddy. Called me and caught me in a lie. I ment a turbocharger! Duhhh?? Sorry for the confusion!
But you can buy a new crate 3.2 LS2 engine from a dealer in California ( of maybe I'm lyin' and it's really Florida) Anyway. some place far away,, and they swear you can drop the 3.2 into any Catera but ya have to keep the old oil pan, and wiring harnes/computer etc. And the oil filter. See the commotion about that on another thread.
By the way I stopped into a used car dealer in Guelph Ontario and he had a 98 Catera with only 98,000 km on the odometer. Engine compartment and components were clean and vurtually rust free. The body was solid, the interior showed minimal wear except for the drivers door handle/latch area.Wanted 9 large for it.
Right next door was a 2003 CTS with 119,000 km. The engine compartment looked like it was packed in salt and left to rust. But it has the 3.6 liter engine. Didn't take it for a drive but it sounded good and the rev limiter when in Park or neutral would only let the rpm top out to 3 grand. Nice little feature. Wanter 17 g's for it.
Anyway enough babbling.
See ya on another thread soon.

07-23-06, 03:02 AM
To reduce compression you need dish top pistons. Shorter connecting rods will increase the quench area causing bad air fuel mixture and bad combustion in the chamber, among other possible problems.
The CTS 3.2L is a LA3, the LS2 is a 400hp 400tq V8 or the 73/74 Pontiac super duty 455cid V8.
$9000 seems fairly steep for a 98, you should be able to get a 2000/01 sport for that price with the same km.
The turbo setup from the Saab would not be a direct bolt on. Because the Saab motor was transversally mounted the turbo is mounted directly to the manifold, on the Catera the frame rails would be in the way.

07-23-06, 10:28 AM
Thanks for correcting the info. Serves me right for relying on my memory instead of checking the data. :worship: