(G) removing cat

Hi there, I just inherited my Mam's '93 999cc FIRE 5-door. Having (yet) no license, and a random untraceable oil leak, I did what any bored person might on an empty, hot, summer's day and removed the cylinder head. Since then the engine has been stripped as far as possible with it still in the car... the sump & oil pump are off, the radiator's
out and flushed... the valves have been removed (to be cleaned and reground) and I'm decarbing the pistons & combustion chambers. Considering the same oil had been in the car for about three or four years, there's not much wear abound - the cam bearings are looking lovely, and I can see my undistorted mug in all 8 of those shims atop the tappets.

While I'm at it, I've polished the exhaust ports on the head, and I plan to do the same on the exhaust manifold. Those nuts are absolute buggers to undo, and I ended up taking the whole downpipe (including the cat) off the car for extra clearance. What I'm wondering is, can I scavenge a cat-less downpipe off an older, scrapped Uno and fit it to mine for the sake of a couple of HP (to be switched back come MOT time)? Mine's the downpipe with the cat right beneath the manifold flange - so close I can't get a socket on the flange nuts, the damned eco-friendly thing.

If anyone knows anything about this, or indeed a way to scrape the mating surface of the cylinder head as clean as Mr. Haynes insists without knackering the alloy, I'm all ears.

Cheers,

Paul

I should add on the exhaust subject, will an older downpipe fit my current flange bolt pattern (and shape), and what of the wires to the lambda sensor, cos I'm sure the Bosch dude under the dash will want to know what's going on there.

I should add on the exhaust subject, will an older downpipe fit my current flange bolt pattern (and shape), and what of the wires to the lambda sensor, cos I'm sure the Bosch dude under the dash will want to know what's going on there.

Hei Paul.

I've got the same cat. project as you. My plan is actually to cut the cat. off on both ends, and replace it with an extension. Then when the MOT approaches, replace the cat. for a day with clamps etc.

I haven't done this yet, because I'm out of friends with a garage that can elevate the car from the floor. Good luck whatever you do.

Morten.


gas lowered on abarth wheels. upgraded interior and visuals. audio through phoenix gold and kenwood.

projects: air in and out.

Well... I specially got hold of an 11mm spanner to undo those flange nuts today, then found only one is 11mm and the other two are 12mm (why?). Then I went a bit too heavy on the 11mm one and totally rounded it off. An hour's worth of Dremel-ing did no good, thanks to the catalyst being in the way, and the nut and stud now appear to be a big shiny welded mess. And it rained, all the time.

So, I'm going the scrappy and getting another manifold/downpipe combo, ideally a manifold with a lambda sensor and a pipe without a cat. I'm going to leave the other thing while the joint's still sealed.

Wish me luck...

Good luck. I never leave home without WD-40 in the spare wheel. Actually FIAT has been very clever with the spanner sizes around the car. Where there are bolts and nuts, they are often size 12 and 13. So you won't have to buy two of the same size.

Hope I don't run into the same probs.

Morten.


gas lowered on abarth wheels. upgraded interior and visuals. audio through phoenix gold and kenwood.

projects: air in and out.

Yes, as Morty has said, you shouldn't attempt to undo ANY nuts/bolts/screw etc. on a 10 odd year old car without a serious amount of WD-40/Parrafin/any sort of method of chemically starting to shift the rust.

Hope you have had better lucky today Paul.

Regards
Paul

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Uno 1.0ie Start. Standard.