Technical Punto engine swop - fitting mk2/3 16v into mk1 16v

[fostertom]

Say I got a mk1 42mpg 16v Cabrio and a crashed mk2/3 47mpg 16v Saloon. What wd it take to fit that mk2/3 engine into the mk1 16v Cabrio? Wd it be the whole engine or just the top end and ancilliary bits, ECU etc?

A 47mpg Cabrio wd be significantly economical for a few yrs and wd still be a dirt-cheap car.

What about a 6sp box out of a Sporting - wd that drop in OK? The Sporting's nominally only 45mpg for same bhp etc. Wd that be due to shorter gearing in the 6sp box?

 

[fostertom]

Just moving this back to top - i'd appreciate members' wisdom on this. elsewhere I've seen warnings that the entire loom wd have to be changed, with additional body sensor/ECUs of later model plugged in, otherwise the ECU wouldn't work.

 

[shawzy]

seems a bit extreme to gain the odd 5 mpg,a good service should see a few more mpg,s,thanks.ad

 

[fostertom]

I dunno - 5mpg over 4yr life @ 12k a yr = 122gal saved = 555 litres @ £2.40/litre averaged over that period (prob much more) = £1332 saved. 47mpg with gd performance and maybe 6sp box will do me nicely until decent all-electric cars become affordable s/h. I'm coming from the perspective of a ELX90 Cabrio owner, v happy apart from 35mpg and £220pa tax.

When cars were electronically simple, wd have been an easy swop. No point in doing this unless the ECU etc works 100%. So what's the hidden problems?

 

[Noddy]

If you get a Mk1 16v cabrio and then recon the cylinder head & full service you will get nearer the 45mpg for a lot less effort.

If you are replacing the engine in your 90elx then go for the newer engine and do as above as you will have to replace the wiring, ecu etc with either engine.

 

[fostertom]

Not planning to put a 1242 into the 90ELX.

Put the question another way -
What's the difference between a mk1 ELX85 engine/box and a mk2/3 ELX 85 engine/box?
Is it just in the cyl head and/or ECU, ancilliaries?
Is bottom end and box the same?
What other differences - additional sensors etc around the car, which have to be wired in before ECU will work?

 

[m20b25]

Not planning to put a 1242 into the 90ELX.

Put the question another way -
What's the difference between a mk1 ELX85 engine/box and a mk2/3 ELX 85 engine/box?
Is it just in the cyl head and/or ECU, ancilliaries?
Is bottom end and box the same?
What other differences - additional sensors etc around the car, which have to be wired in before ECU will work?

Mk1 85 ELX has an underfloor cat, return fuel system, different managment system, different tb, different manifolds (both inlet and exhaust),no cam sensor, 1 oxygen sensor, less holes in the cyl head (which is different from the mk2) and a bigger oil filter. The mk2 is called an 80 too not an 85 as it has only 80 bhp instead of 86 (and to further confuse people out there there was a third managment system with 82bhp available in very early mk2 1.2 16vs). Apart from that, theyre the same engine

Gerboxes are identical except for extra mounting holes in the mk2 boxes

Ive put a 97 Sporting engine into a mk2 Sporting. It was a pig to fit and get working. Its much easier putting a mk2 into a mk1, both engine and box, which ive also done

As for putting a 6 speed, dont get caught out like i did with my Bravo. I lost full lock on the right due to the extra cog...

 

[fostertom]

Ah! a man who knows.

Is it right that all those differences between mk2/3 and mk1 cd be fitted to a mk1 shell, if a mk2/3 donor car was sitting there?

"Apart from that, theyre the same engine " - does that mean the mk1 block can stay in the car and all the mk2/3 bits fitted to that?

"Its much easier putting a mk2 into a mk1, both engine and box, which ive also done " - that's great news - what exactly was easier, problems avoided?

They say there's additional sensors etc around the mk2/3 body, which wd have to be installed into the mk1 and connected before the ECU will work?

"putting a 6 speed ... I lost full lock on the right due to the extra cog..." - does that mean that the 6sp box housing is bigger and fouls the wheel/suspension?

Does the Sporting 6sp have shorter overall gearing than mk1 ELX 5sp, up to 5th? Is 6th like an overdrive, taller than ELX 5th?

Thanks in advance.

 

[fostertom]

Is a mk1 bottom end i.e. block, pistons etc near enough same as a mk2, or different?