[AJHWestoz]

Hi

My first attempt at posting;

I have a 98/99 9-3 convertible with B204E low pressure turbo with blown head gasket and some blow by.

Bought a cheap 9-5 Aero B235R wagon with lower miles and running well (or was after I reconnected pipe between turbo and throttle body).

Plan is to transfer engine and probably gearbox too into the convertible.

Got more complicated when I realised the 9-5 has a different Trionic version to the 9-3 and also has fly by wire throttle and other complications.

If I just bolt in the bare engine etc, I am likely to lose lots of power by dropping 10psi of boost and the extra modes on the gearbox.

I am not sure if it is possible to transfer the ECU and loom etc from the 9-5 without manually rewiring the car.

Hoping someone has some experience with this or can give me some hints.

 

[seriks1]

Spend an afternoon replacing the head gasket. That 9-5 offers little or no benefit to your T5 9-3 troubles

 

[AJHWestoz]

Yes but

Except of course an extra 53 kilowatts!

And assuming it's just the gasket; Previous owner drove it for some years with leak, so worried whole head will be rotted.

 

[seriks1]

Well, the transmission just flat out won't fit the car, and ideally you'd use the 9-3 head on the 9-5 block (exact opposite of the usual b2x4/b2x5 hybrid build, which is well documented on this site). Trouble there is reducing airflow, and raising compression on a less stout block than you already have. You can put the 9-3 intake on the 9-5 head and make the car run, but the angle the injectors spray into the combustion chamber will be way less than ideal. Rewiring the car to t7 may not be impossible, but would certainly be a fool's errand.