I'm looking to buy a Coop, I'm presently an Alfa 155 owner.
My 155 has the last real alfa twinspark engine with 8 valves and a chain driven cam, this was later replaced by an Fiat engine with a 16valve belt driven cam.
In my opinion the 16 valve engine is inferior, overly complex and liable to catastrophic failure due to the rubber band failing after 30kmiles.
SO...(deep breath) my question is about the origin of the engines fitted to the Coop.
I've read the 16v engine is based on the Lancia Delta unit, and I've heard that the 20v engine is based on the Fiat unit as fitted to the later 155s.
Some clarification please, 'because if the above is true I'm after a 16vt.

Hello cousin 155 owner; thought I'd chime in here as you haven't had a reply yet.

From my limited knowledge, yes the 16 is a Lampredi, both 16v & 20v have belts.

The 16v belts are indeed fragile and need to be changed more often than the 20v. Replacement 16v engines are VERY THIN on the ground, whereas 20s are two a penny relatively.

FWIW the belts don't so much break on the 20v: the aux belt is more liable to go or fall off and takes the cambelt with it. There are one or two aftermarket solutions to help discourage this though.

Don't know if this is any help at all, but welcome anyway

the 16vt engine has been around a long time in one guise or another it is the same virtually as that in the integrale bar turbo /downpipe that type of thing..its been in quite a few fiats lancias and i think even alfas.. its morphed into a 16v from its original 8 over the years and has proved to be a good strong unit for both road car and motor sport(tunes well)..the 20vt is a newer thing..what its based on i couldn't tell you ,i know very little! but am prepared to share that little as you havent got much else in the way of information yet,i am sure some one that does know will come in and make me look daft but i will learn something from that so care not ..
all i can tell you about the 20vt is that it is a real strong engine and a lot of guys are running 350+ bhp with over 300 ftlbs on standard internals if you stick around the 300 mark they are happy and can tolerate it seemingly without issue ..i wouldn't say either are prone to failures nothing in particular anyway and considering the number heavily modded are a safe bet ..i wouldnt say either was stronger or better in anyway just different ..if it w3as as easy to get parts for 16v it would just be a case of which one drives the best for what i want to do with the car..well i hope this is of use sorry i don't have more solid facts for you

I've just dug out my copy of the book 'Twin Cam Italia', Phil Ward's history of the Lambredi twin cam, if you've any specific questions. It was originally 1.4l, carbed, and 90bhp back in 1960. There's a good section in the book on Fiat Coupes and Lancia Kappas and the author's impression of the later 'superior' (his word) 20v engine is "although not a Lampredi design, it is certainly a natural and worthy development of the original concept".

Further to what I said earlier, the 20v also gets better fuel consumption over the 16v.

YellaFella, what are these 2 aftermarket solutions to help discourage the belt situation?
Im aware of 1, through JBT. (uprated pulley)

Yeah, the JBT pulley (which I have). I'm sure there has been a previous similar thing too, but yes the JBT solution is the only one atm I believe.

What i would like to develop is a visco bottom pulley.But never had the time to do it.
This would still allow the aux side to spin at enough Rpm to power the steering ac and alternator etc,as they only really need about 500-800 rpm.
The main advantage would be to improve engine spool up and torque as well as preventing a belt failure.