Is the S40 engine the renault 16 valve unit.

http://cgi.ebay.co.uk/2-0-TURBO-T4-S40- ... dZViewItem

Looking at that pic the manifold looks the same.

Nope. All petrol engines on older S40's are Volvo made. GDI diesel is from Mitsubishi.

gdi isnt the diesel - the gdi is one of the 1.8 engines available - stands for 'gasoline direct injection' - 125bhp 1.8, with better fuel economy iirc

not sure where the derv is from, but all the other petrol engines are the same as the 5/6 cylender engines in bigger volvos, just with a couple of pots knocked off..

GDI engines are one of the few that can not be converted to LPG without major mods.

The manifold does look very similar to the renault 16v snail shell set up.
I thought they were volvo but that pic raised questions to me.

The S40 engines are 4 cylinder versions of the N and RN series engines from the 850 ( 5 cylinder ) and the 960 ( 6 cylinder ). The current S40/V50 uses volvo 5 cylinders and Ford 4 cylinders.

These engines are all aluminium. However, the Renault laguna 2.0 uses the volvo engine...."1995 - Station wagon launched, and 2 litre 16V Volvo engine added to range"

The GDI is a lean-burn engine using petrol. It has specially shaped pistons and has two operating modes. In lean mode a lean mixture is used and the swirl is design to make a richer mixture at the plug but with the remaining mixture in the cylinder being lean. This offers better fuel economy. Under acceleration, the engine mode changes to an Otto cycle. The petrol is injected during the compression stroke during lean burn operation hence the engines name "Gasoline Direct Injection"

There are some problems with these engines tho... strangely they seem to coke up and decoking isnt uncommon... a rarity nowadays with the leaner burning engines. Volvo used this engine in the first S40/V40 and it was badged a 1.8i... the I was a larger badge on the boot.....Volvo couldnt afford to develop their own GDI engines.

VW and Audi have GDI but call it FSI... fuel stratified injection.... I need to do come more research but I think this operates in the same way....