gutted cat, will it work ok?

[mr2nut123]

http://www.imoc.co.uk/forums/viewtopic.php?t=44483

Im thinking about swapping my cat for this decat pipe on my rev2 tubby. The guy mentions that the temp sensor has rusted in and spins freely. Now im not that up to scratch with technical stuff on this, what exactly does it mean? Will it work fine or will the temp sensor affect anything to do with engine temps or cause any long term damage?

[ginga]

To fit that you will have to remove yours anyway. Why not just gut your own . All that is required is a big screwdriver and a hammer.

[mr2nut123]

ive heard bad stories of the bolts rusting off when removing the cat. if that happens ill have no car until toyota can get some in. can you buy these bolts from a club shop or anywhere online incase this happens? i might give it a shot myself then.

[mr2nut123]

To fit that you will have to remove yours anyway. Why not just gut your own . All that is required is a big screwdriver and a hammer.

i wanted to keep my standard cat for MOT time or will a 93 rev2 be ok?

[paul port]

It's N reg Turbos and onwards that have CAT issues when it comes to MOT time...

Gutting Cats,
I would personally advise taking the cat and turbo elbow off as a complete unit... It's much easier, you are less likely to snap bolts, as the turbo elbow studs are quire strong.

Forget about Gutting the old cat - just stick a replacement downpipe on there instead... the cheap Ebay ones are OK, just be sure it comes with the lower support bracket.

Paul

[mr2nut123]

It's N reg Turbos and onwards that have CAT issues when it comes to MOT time...

Gutting Cats,
I would personally advise taking the cat and turbo elbow off as a complete unit... It's much easier, you are less likely to snap bolts, as the turbo elbow studs are quire strong.

Forget about Gutting the old cat - just stick a replacement downpipe on there instead... the cheap Ebay ones are OK, just be sure it comes with the lower support bracket.

Paul

im on a tight budget at the moment so ideally want to keep this to been a free upgrade. Can you take the cat off as a complete unit, smash the insides out then replace with no fear of the bolts snapping?

[johnnymr2]

yeah the best way is to remove the cat all together and the guts should just drop out. there is a good thread in the knowledge base explaining how to remove the cat, have a look

[mr2nut123]

yeah the best way is to remove the cat all together and the guts should just drop out. there is a good thread in the knowledge base explaining how to remove the cat, have a look

cheers for that mate. Got the instructions printed off. Where can i buy these replacement bolts and gaskets before i do the job?

[johnnymr2]

you could try any motor factors or exhaust unlimited, they should stock the gasket. the bolts you could prob get from any hardware store i dont think they are anything special, but make sure you get good grade stainless, A4, then if you have to take them out they wont have rusted, also worth putting a bit of copper slip on when doing them up

[MR!! wren]

does anyone know if gutting the cat even has a decent effect on power anyway, i read somewhere that they actually dyno'd less power after gutting the cat. they put it down to toyota having tuned the length of the exhaust pipe. i personally think it would be because the empty cat chamber would act exactly the same as an expansion chamber on a two stroke engine, which are spcifically designed to increase back pressure. any thoughts?

[dawolf]

It's N reg Turbos and onwards that have CAT issues when it comes to MOT time...
Paul

I'm sure that's not true, all cars manufactured after 1993 need a cat fitted for the MOT, even imports (unless they manage to scrape through without).

[paul port]

It's N reg Turbos and onwards that have CAT issues when it comes to MOT time...
Paul

I'm sure that's not true, all cars manufactured after 1993 need a cat fitted for the MOT, even imports (unless they manage to scrape through without).

The difference is, when a MOT tech looks up the MR2 (SW20) chassis on their gas analyzer, they will only find the 3sGE normally asp engine listed.
When you point out you have a 3sGTE fitted, they end up performing a generic test for the model year.

Pre N reg (a month and year is listed in the official docs, but basically 'N' is the delimiter) the test assumes no cat.

N reg and onwards, the generic test assumes there IS a cat, and therefore has limits that are nearly impossible to pass without one.

Paul

[Draven]

It's N reg Turbos and onwards that have CAT issues when it comes to MOT time...
Paul

I'm sure that's not true, all cars manufactured after 1993 need a cat fitted for the MOT, even imports (unless they manage to scrape through without).

The difference is, when a MOT tech looks up the MR2 (SW20) chassis on their gas analyzer, they will only find the 3sGE normally asp engine listed.
When you point out you have a 3sGTE fitted, they end up performing a generic test for the model year.

Pre N reg (a month and year is listed in the official docs, but basically 'N' is the delimiter) the test assumes no cat.

N reg and onwards, the generic test assumes there IS a cat, and therefore has limits that are nearly impossible to pass without one.

Paul

Tis true. What paul is saying is exactly correct. I have done my research...

[Antstarr]

So mine being an early rev3 turbo model reg in 93 as L reg would mean I dont need one anyway? Dont people have difficulties getting pass the MOT with a DP?

[dansREV2turbo]

if its before june '95 (iirc) then no probs with a down pipe.
the only problem you can get is the tester not knowing what hes on about!