Technical mk1 1.1 to 1.2 8v swap

[Scott8105]

Hi all a newbie to the forum but a long time lurker and you guys have helped me many times with the wealth of information in this forum.

My Fiat days started more years ago than I'd like to admit with a 1.6 131 mirafiori - so that's a clue !

Well I'm back with trying to keep the other halfs mk1 Punto on the road - its become a challenge this year. latest episode saw the head drop the end off a valve (it's a 1.1 8v and the cam belt was intact but it had been using loads of oil) and the valve bounced around in the engine destroying the head and punching a hole in the piston ( pics available if you're interested ). So a quick ring around has found me a 1.2 8v Spi head and block which I have duly installed with the hope for a reasonably straight swap. So two things that have halted my progress: -

1) the down pipe is too short (gutted its a month old).
2) sump is leaking - rusted through and the 1.1 isn't compatible - I think!

So I ask the fiat expert masses, can I buy a 1.2 down pipe and marry to the 1.1 cat ? Is the pipe diameter the same?

And secondly is there anything else I need to change? I think the ECU should be okay reading the other threads. It's all gone in without trauma so far.

Thanks in advance for any help.

Scott

 

[fingers99]

1) the down pipe is too short (gutted its a month old).
2) sump is leaking - rusted through and the 1.1 isn't compatible - I think!

Use a spacer between the manifold and downpipe. About 10mm should do it. 2 gaskets.

Sumps are not interchangeable. But they're cheap. Some clown has removed all the sumps from the Puntos in the local scrappy.

Pretty sure pipe diameters are the same, but I'd try the spacer trick.

 

[Scott8105]

Hi, thanks for the quick reply. I have a spare manifold and considered cutting the flange off and trying to drill a clearance hole but then thought the studs probably won't be long enough and don't look like they will free easily to replace with a bolt.

 

[fingers99]

If you can get some heat and GT 85/Plus Gas on them they should free alright. But, yeah, cutting an old flange (or two) is a good way to go. A trick often used for 1.2 Cinq conversions.

The other way to go is a simple weld in extension to the existing downpipe.

 

[Scott8105]

Anybody out there got a dipstick for a 1.2 8v mk1 Punto? EPER says that the 1.1 and the mk2 8v ones are different! My replacement engine was missing its dipstick so need one to avoid overfilling. Using the 1.1 to plug the hole at the moment but not along term solution. Scott.

 

[Scott8105]

I just wanted to make people aware of a few teething troubles or things to watch out for if you consider doing this swap, especially if you are swapping ancillary parts from the 1.1 engine.

The following items are not common so make sure you have the parts from the donor car or they are with the new engine.

1) cam belt is different, you should have a new one to fit anyway but make sure you have the part number, or old one from the new engine. Your registration number doesn't help now at the motor factors.
2) The exhaust down pipe as in the thread above is different, if you are fitting this in a Punto mk1 then the easiest and quickest solution is to get a new downpipe for the 1.2 this cost me £25 new off an eBay supplier and much easier than making spacers.
3) The dipstick on a 1.2 is longer than the 1.1 so make sure you get it with the engine, using the 1.1 stick will mean you overfill the oil.
4) The cam belt cover is different, looks exactly the same but the 1.2 is again about 10 - 15mm longer.

Other than that it all marries together fine and the engine seems to run fine on the 1.1 ECU once it's settled down to the new engine characteristics.

As an improvement to the 1.1 the 1.2 is a much less frantic drive and the engine has a better amount of torque lower down which makes gear changes less frequent.

Hope that helps someone.