Has anyone ever heard about swaping the stock 928 engine with the Cayenne's V8? There is nothing like the styling of the 928. I've considered buying one for years but don't want the hassel of a 25 year old euro with 100K miles on it.

So what are the chances of swapping the engines?

 

Ok, I was poking around and found a page that talks about a Corvette/928 engine swap which is interesting but I wouldn't feel right doing that to the 928. It's not as bad as the corvette/testarossa but it is pretty bad.


http://www.renegadehybrids.com/928/928.html

 

It's a very good swap, the GM LS engines into the 928 or 944. On a per pound basis the LS V8s (they vary from 5.7 to 7 liters displacement and 350 to 505 SAE net HP) are much more powerful than just about any other options, and their packaging is superb -- they are low, narrow, and short for their displacement and power, so they fit in lots of cars that you would be surprised to find them in (Miata), and they weigh less per HP than just about anything else in their HP class (the 7-liter 505 HP version weighs less than a 4.6 liter DOHC 320 HP Ford V8).

Back to your question. You can do anything if you have enough money. This would be frightfully expensive: you could afford to restore a good 928 and pay years of maintenance for what it would cost to do it right. My advice: wait for the new "928" (2-door version of the Pan America) which will have the V8 in it, or go with a GM V8 conversion kit.

 

I've thought of investigating a swap like that too. Twin Turbo Cayenne engine would be awesome!! How creative and capable are you? Plenty of spare time, and all the knowledge of the engine. Electrical would be a challenge. New engine controls are all multiplexed (CAN stuff). You'd need an aftermarket controller, that's a big project on it's own. Porsche enignes (new and old) are very very complicated with every little gismo and gadget to make them the most convenient and comfortable cars when they are new. You'd be better off getting a 928 crate engine from 928 International and putting an aftermarket EFI system on it.

 

I would also like to know if the Cayenne twin turbo could go into my S4! Any thoughts ???
Thanks fellas!

 

By S4 do you mean an Audi S4 , or a CarreraS4? Either would be difficult but for far different reasons.

As always, you can do anything with enough money, but neither transfer would make too much sense. The Audi would be very difficult for nearly any engine transplant due to the four wheel drive nature of the car and the incredible tight fit (puttingthe stockV8 in there was a tight fit for Audi itself). You'd do better to upgrade to the RS4 engine, or mod the stock engine, or just trade for a new RS4

Putting the Cayenne V8 in a CarreraS4 would ruin the car's balance and require major body and powertrain surgery, and result in no more power than you could get with mods to the stock engine.

 

Hello Lee and thanks for the post.
At least for me, the designation "S4" in this post means 928 S4. I think that's what this string of posts is dealing with. If I'm wrong... then I think I'm in the wrong place with this question!!!!
Thanks guys

 

You can usually get anything to fit but as Lee Willis says you need either lots of money to throw at it or engineering capability, and a willingness to work away at each problem you encounter until it fits and works. Remember that if you end up changing the effective centre of mass mounting point of the unit etc then this may impact on handling, and that is another set of problems to solve. Good fun though if you have time!
Regards big Bob

 

+1 on Chevy LS - Renegade Hybrids sells kits, not sure of any other companies.

 

Best solution would be to find a nice 928 S4 or GT(87-93) for aroud 20K and get a $7000 supercharger kit if 326 HP is too little for you. They are very simple to install or have installed. The Motronic Engine management is still similar to the modern Bosch systems and would be reliable and maintainable. In most cases the engine managemnet systems would be able to handle the extra squeze from all but the most insane setup. I think 500 HP is very realistic and much less work and cost than either option listed to date.

The idea of anything but the best sounding smoothest V8 ever produced being transplanted in a 928 is like marrying a supermodel and keeping her locked in a dark closet, what's the point?

Note: the 928 is not supported by Porsche now for many years, so you will need to find your own German Mechanic or learn to do it yourself. No money in maintaining a very reliable well built car and Porsche dealers are all about making money.

My '78Black onBlack65K BSP autcross 928 $.02.