Weight different between XU alloy & iron blocks?

Anyone know how much heavier the iron XU blocks are compared to the alloy
ones? It seems like most/all 1998cc XU engines are iron blocks - such as the
Citroen XM's 2 litre turbo engine, or the 2 litre 16v engine fitted to later
405's. Just wondering what I could expect to happen if I had a heavier block
than my current 1905cc alloy engine.

Yes, I'm *still* deciding what to do with my 305 engine and exactly how mad
I should go - all the while driving it to work every morning with an
alarming ticking noise worsening as the days go by.

Chris.

 

Hi,

the
No clue.

Post-93 XUs (XU8-XU10) are iron blocks, possibly to comply with noise rules.
They also came with a catalyzer and you may need a lambda probe to get a
correct run.

Wow, you're heading for another big job - anyway you've already done that
once.

 

Hi G.T.,

Yes, that 405 cylinder head I put on the car a couple of years ago is
deteriorating and I could probably do with a full engine rebuild. To be
honest, I'm surprised it lasted this long as it had somewhere in the region
of 120,000 miles on it and it came off a car in a breaker's yard that
couldn't be started. I figured I'd put it on and see if I could get it to
work and then if things went well, refurbish it later. It ran so perfectly
straight away, that I didn't ever bother to take the head back off!
Now it seems to be burning oil (probably still within the huge tolerances
set by Peugeot though!), and it's making a clicking noise from somewhere on
the head - it starts off very loud under acceleration and gets quieter as
the car warms up.

So, basically I can either get the engine rebuilt or get a new engine. I
must admit, I rather like the idea of getting the 16v engine under the
bonnet

I've seen a Citroen XM turbo engine up for sale recently, but I think it
might be too heavy & have far too many components to get into my engine bay!

Chris.