77 Scorpion Engine Swapping Recommendation

Engine Choice Suggestions

  • Honda

    Votes: 0 0.0%
  • Other

    Votes: 5 100.0%

  • Total voters
    5
A Busso engine would definitely be my choice were I to contemplate an engine swap. That said, while the belt change isn't too tricky on my Alfa Milano Verde, it would be cramped quarters in the back of a Scorpion. Maybe no worse than with the original engine? The worst job would be any work on the V-6's rear bank -- a cylinder head gasket would probably have to be an engine-out job. Even a valve adjustment would be tricky, I think. Also, Alfa parts aren't cheap -- typically not as bad as Porsche parts (yikes!) but most bits are multiples of what the equivalent Fiat twin-cam part is. And there's 50% more engine.
Not sure how hard the belt would be but not really concerned about the rest. My daily driver Milano went 175k miles before it needed any engine work.
 
Keep the Lampredi twin cam but male it 16 valve...either with a complete 16v swap or just swap the 16v head on to the existing 8v block.

SteveC
 
Not sure how hard the belt would be but not really concerned about the rest. My daily driver Milano went 175k miles before it needed any engine work.
Wow! My car has had two head gasket jobs -- one at around 60k miles and another at 155k miles. The original gaskets used on these cars were a two-piece design that usually failed early. They were replaced with a one-piece gasket which was more durable. The first owner of my Verde drove it daily, I bought the car from his estate after he passed a few years ago and it only does a couple thousand miles a year now. It came with a two-inch stack of service receipts representing perhaps $10k of repairs.
 
The
Wow! My car has had two head gasket jobs -- one at around 60k miles and another at 155k miles. The original gaskets used on these cars were a two-piece design that usually failed early. They were replaced with a one-piece gasket which was more durable. The first owner of my Verde drove it daily, I bought the car from his estate after he passed a few years ago and it only does a couple thousand miles a year now. It came with a two-inch stack of service receipts representing perhaps $10k of repairs.
The official change over to the one piece gasket was dated 5/88 I believe. But my 87 Milano had the one piece gaskets already installed from the factory.
 
Honda K20 / K24 ok for the exxe, IMO not for the Scorpiacarlo as it is more of a Grand Touring car. Alternative power train is on the to do list for the Scorpiacarlo project..

Power train choice will be a Saab B234R in stock tune. OEM of 225 Bhp / 250 lb/ft torque about 3,000 rpm. Does not sound like much, until you've been around a B234 turbo for a few decades. The original Saab-Scania design and production engine was quite capable of twice that power output (450 bhp / 500 ft/lb of torque) with proven reliability on stock OEM internals.
They are famous for digesting gear boxes with a slight burp connected to them due to the torque they are easily capable of producing.... as this LeMons team discovered upon installing one of these into a Nissan 300ZX. The boost was upped, the Nissan gearbox became ground up metal bits.
http://www.roadkill.com/lemons-forget-ls-swaps-drop-turbo-saab-engine-z-car/

Does good in boats too.
"Hi! And thanks for all your comments. Sadly this summer went how it went. We weren´t able to get a correct Counter-stern so it was a no go. I´m trying to get one from the States this winter, so hopes are high for next summer. Turbos are now upgraded to TD04-15T´s :) We are starting with approx 450hp with base-software. Cheers!"


The earlier Saab B202 (two liter, twin cam) was used in the barber Saab series with zero failures or problems from direct off the production line engines. This is extremely telling of Saab's engineering, design and production of these turbo engines.
https://www.eeuroparts.com/blog/7723/formula-cars-with-saab-engines-the-barber-saab-pro-series/

Then we have the Saab-Fiat-Lancia-Alfa Romeo connection..



Bernice
 
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Honda K20 / K24 ok for the exxe, IMO not for the Scorpiacarlo as it is more of a Grand Touring car. Alternative power train is on the to do list for the Scorpiacarlo project..

Power train choice will be a Saab B234R in stock tune. OEM of 225 Bhp / 250 lb/ft torque about 3,000 rpm. Does not sound like much, until you've been around a B234 turbo for a few decades. The original Saab-Scania design and production engine was quite capable of twice that power output (450 bhp / 500 ft/lb of torque) with proven reliability on stock OEM internals.
They are famous for digesting gear boxes with a slight burp connected to them due to the torque they are easily capable of producing.... as this LeMons team discovered upon installing one of these into a Nissan 300ZX. The boost was upped, the Nissan gearbox became ground up metal bits.
http://www.roadkill.com/lemons-forget-ls-swaps-drop-turbo-saab-engine-z-car/

Does good in boats too.
"Hi! And thanks for all your comments. Sadly this summer went how it went. We weren´t able to get a correct Counter-stern so it was a no go. I´m trying to get one from the States this winter, so hopes are high for next summer. Turbos are now upgraded to TD04-15T´s :) We are starting with approx 450hp with base-software. Cheers!"


The earlier Saab B202 (two liter, twin cam) was used in the barber Saab series with zero failures or problems from direct off the production line engines. This is extremely telling of Saab's engineering, design and production of these turbo engines.
https://www.eeuroparts.com/blog/7723/formula-cars-with-saab-engines-the-barber-saab-pro-series/

Then we have the Saab-Fiat-Lancia-Alfa Romeo connection..



Bernice

I know the saabs well, I have an 03 93 and find it to be a great car which is why i suggest the ecotec. The Saab mill would've easier to swap...at least i think it would be when it came to the wifi. The ecotec is a bit of an issue on the electronics. I'm thinking the b234 would be really heavy though....and no 6 speed!
 
2003 Saabs had GM_ized saab motors that have been cost reduced and re-designed for fuel economy or fragile. These would be the B205 - B235 series and they are also prone to engine oil sludge due to a poor PCV design...which was revised about six times. If a Saab power train is considered at all, it must be a Saab-Scania B204 or B234 made between 1991 to 1999. About 2003 three years after GM took 100% of Saab, production of the Saab B series of engines was not possible due to the Scania foundry being sold to VW. This is why GM Ecotech ended up in later "GM-Saabs".

The B234 is not that much heavier than the Lampredi DOHC. Have a look at a bare post 1993 B204-B234 block, it is remarkably small and not that heavy. The cylinder head is definitely heavier. Overall not too bad.

Keep in mind the Saab Tronic engine management is essentially open source software allowing users to tinker with one of the most tunable and technically advanced turbo engine management systems made.

BTW, the con rod to stroke ratio for the Saab B204 is 1.96 which is race engine numbers.

Busso V6 about 1.82 which is GOOD.

GM ecotech con rod to stroke ratio is about 1.55 or utility engine numbers.

Serious race engine con rod to stroke ratio often exceeds 2.

Do not be drawn to power by spec sheet alone. There is much more to this than the spec sheet numbers which often tell little of what the engine's personality or potential really is. Essentially what is desirable is a bore in the 85 to 90mm diameter with short stroke and large connecting rod to stroke ratio. These are basic performance engine requirements. More cylinders is not better, there is a trade off between valve area -vs- friction -vs- displacement. More cylinders results in more friction or power loss trading off for flatter torque curve -vs- engine RPM. This become more balanced as engine displacement goes up or why a 12 cylinder 27 liter engine is not too bad a trade off while a 2 liter 12 cylinder has too much frictional losses and pinched valve area possible. During the glorious Formula One 3 liter V10 era, that was no accident to decide on a V10. It was much to do about valve area -vs- displacement -vs- bore diameter -vs- con rod to stroke ratio.


The Saab F25 gear box became a GM gear box and has been used in a variety of GM vehicles. This is one of many items GM got from purchasing Saab. Later variants are F35 and F40 which were made as six speed and LSD was an option. The number designation notes the torque rating of the gear box. Having a six speed is not as important as having the proper gearing relative to engine power curve, tire-wheel diameter and expected speed in gears. It is not how many gears, but if the gears match the overall power train and chassis-suspension system. Regardless, keep in mind a tuned up Saab-Scania turbo engine can easily produce more than enough torque to digest the majority of gear boxes available that would fit this transplant.

If the Saab route is considered, know the post 1993-4 power trains are shorter than the first introduced B234L and gear box series used in the 9000. These first generation power trains are about 96mm longer than the later versions which will affect power train fit into the Scopriacarlo.

The reasonable alternative is the Busso V6 or Ferrari-Ducati V8 used in the Lancia Thema.


Bernice


I know the saabs well, I have an 03 93 and find it to be a great car which is why i suggest the ecotec. The Saab mill would've easier to swap...at least i think it would be when it came to the wifi. The ecotec is a bit of an issue on the electronics. I'm thinking the b234 would be really heavy though....and no 6 speed!
 
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