e110at

This ok to do on newage wrx not sure when I'll get it mapped, only cat left will be in the up pipe. Is there a big difference in noise?

RS_Matt

I removed cat from up-pipe and fitted bigger STI top mount, I ran it for 3 years without a map. Even with cat taken out of up-pipe the noise was noticeably louder (growlier) over 4k.

SAM-UK300

iTrader: (8)

On newage if it is a decat downpipe you will need a map

e110at

I am planning on a map just not sure when, is it safe to run?

360ste

iTrader: (1)

Some will say yes get it re-mapped immediately, or as posted earlier someone has run for 3 years without a re-map. If you don't map and it does go wrong then it is a rebuild or engine replacement. Are you willing to take the chance, upto you.

mozzerscoob

iTrader: (1)

Earlier thread stated he run his car for 3 years without a map removing cat from up pipe. You want to remove cat from downpipe and run it without a map!! Good luck. I mentioned all this to you 2-3 days ago ?

e110at

Thanks for the info

ScoobyFanatic33

iTrader: (1)

is it to annoying to ask you to explain why mapping is so crucial when anything whatsoever is done to the engine ?

can damage really be done so easily ?

what kind of cost is involved in mapping especially if it needs doing anytime something is added or changed ?

Cheers

e110at

Found this

http://www.subaru4you.co.uk/how4.shtml

ST-X

High compression engines (ie.. turbo'd ones) are very susceptible to pinking/det which comes from running lean. If the engine can breathe better (as it will from having a freer flowing exhaust) you will likely be running leaner than ideal at WOT. Not necessarily in daily driving, but if the ECU can't keep the AFR within the required parameters the aforementioned det will occur. You may get away with a little, you may not. This is partly why Evo's seem able to get more reliable power more easily than Subaru's, they seem better able to handle running weak without such a great risk of catastrophic engine failure.

You can take the risk but it's not something I would. Do it properly, or don't do it at all.

e110at

Ill do it properly, just seems like u can't change a bulb without a map on the impreza lol