S type 4.2 to Str engine swap
 

Hi,

I decided to start a new thread as I didn't find any previous topics in this exact matter.

So, I'm currently running a late 2002 S-Type (model year 2003) with 4.2 naturally aspirated v8. The engine is working fine and chassis and other parts of the car are in great condition even though there is slightly over 200k kms on the clock.

However, as usual, there is a constant urge for more power and I've been thinking about a engine swap to 4.2 supercharged version. My problem is that I'm not really a technician and have zero experience in this complicated issues. So if this kind of procedure would be carried out, I would need a technician to do it.

Ok, so the first question is: is it even possible to swap an 4.2 supercharged engine from eg. 04 XJR (one is currently for sale) or 06 STR? What kind of modifications would be needed and what other parts updated?

Thanks!

-JJ-

this has been discussed many times .
any thing is possible - BUT
your problem is as you said it
there is many more things to consider besides the engine swap ,
e.g. fuel system cooling system . and the required loom's , modules and programing . stronger trans . stronger diff . and axle's
and also the brake upgrade . are different between the two models and all these things a mandatory to support STR levels of power .
and paying some one to carry this out will most certainly cost more than starting with a STR . sell the v8 and buy a STR . buy carefully and you wont regret it

Welcome to the forum JJ,

Please post an intro in the new members section when you can.

+1 on the advice above, if you want an STR buy one, it's not just the engine. the chassis set up and the brakes are different and paying someone to do the job would be nuts.

+2

it's waaaayyyy tooooo costly to do it

+3 you've been warned...lol

+4 Don't go down the "engine swap" discussion to another brand engine, this topic has been discussed many times on the forum as well. :icon_beerchug:.

+5
Forget it!
There are just so many different components on an STR compared to a normally aspirated V8 that it is just not worth doing.
The STR's are virtually a completely different car.
If you want a supercharger S-Type you need to purchase one.

Mellow

+6 on not attempting any engine swapping with an S-Type R.

What is wrong with the normally aspirated AJ33?

I'm into engine swaps and have 2 LS projects under my belt.

IMO the S-type is a huge project as compared to others.
If a guy was bent on it (for what ever unreasonable quest) I'd suggest getting a doner car and have them side by side to do the work.

IMO.. an S-Type is just not a car that is worth the cost or effort.

I'm into engine swaps and have 2 LS projects under my belt.

4 engine swaps so far.

IMO the S-type is a huge project as compared to others.
If a guy was bent on it (for what ever unreasonable quest) I'd suggest getting a doner car and have them side by side to do the work.

I have 4 S-types, so I think that is/was possible to have them side-by-side.
S-type Mechanical conversion isn't that difficult, Electrical is the hard part

IMO.. an S-Type is just not a car that is worth the cost or effort.

True. Discussed many times on the forum in the past.

If you're going to switch things around, why not get a wrecked 2010 or later XFR with the 5.0 motor and over 500 HP and the newer transmission with paddle shifters, etc. You would definitely have the ultimate S Type! You probably should switch brakes and suspension components so you can also stop and handle the car, along with the XFR computers where needed. The rear end from the XFR would probably be needed too to handle the extra power also. It still has the same chassis as the S Type, hopefully the wiring harness is not too different too. You would have to do all the same work with a STR, so why not go all the way? A wrecked XFR probably won't cost much more than a wrecked STR anyhow, if you could find one that is. Money shmoney! Time?

First I'd use a good STR with a blown engine,
Then it will probably be difficult to find a complete wrecked XFR with lower mileage, unless you have a used vehicle license and can purchase one at either an insurance auction or salvage auction. Probably have to pay between $8K and $14K in order to outbid other dealers. Then the fun would begin. I'd figure out how to swap in the complete rear sub frame assembly. Once you figure out the engine/mechanical swap, the most time consuming part would be the electrical. (Harnesses, CAN modules, wire splicing.) I really dislike the electrical portion. Instrument cluster, entertainment console and interior power items might be one of the more challenging aspects.
Could be done I suppose given enough ingenuity and time.

What would you have when it was done? Decent powered retro car with an 8-speed trans. Wonder what it would be worth?

If you don't want the ultimate S Type and just want the car to be faster once in a while try nitrous. Maybe others have tried it.