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smokeybone
26-04-2010, 20:28
Hi everyone havent spoken much on here as i have just been trying to get used to the site and get to know as much about the williams as i can.

Anyway, my williams went today for a new center section and decat pipe in my local longlife as my magnex center section had broken and been welded poorly previous to me owning the car.

After collecting the car i noticed that the car didnt perform like it did and needed reving through the gears to go anywhere.

After reading on here i understand that the williams goes better with a cat, what is the reason behind this as i thought that a cat was very restrictive ?

Wobba
26-04-2010, 20:42
Hi everyone havent spoken much on here as i have just been trying to get used to the site and get to know as much about the williams as i can.

Anyway, my williams went today for a new center section and decat pipe in my local longlife as my magnex center section had broken and been welded poorly previous to me owning the car.

After collecting the car i noticed that the car didnt perform like it did and needed reving through the gears to go anywhere.

After reading on here i understand that the williams goes better with a cat, what is the reason behind this as i thought that a cat was very restrictive ?

No, the CAT creates the illusion of going better as it restricts the expulsion of gas from engine and creates back pressure, which for some reason I fail to understand increases the revs low down. However, restricting gas flow also limits the power output.

Removing it may give a tiny bit more poke, but it also shifts the torque curve further up the scale, so you'll get better mid and top end.

Personally, although I sometimes miss the low down torque of a standard setup, I soon get bored of its relatively gutless mid range and top end output, not to forget the butt clenching awesomeness of the massive pops, bangs and flames out the back.

smokeybone
26-04-2010, 20:52
Does it mean that it will go better if driven harder? The car doesnt really get driven very hard normally so not sure if the cat will be going back on. Car does sound nicer with the decat on the overrun tho :)

Wobba
26-04-2010, 23:37
Does it mean that it will go better if driven harder? The car doesnt really get driven very hard normally so not sure if the cat will be going back on. Car does sound nicer with the decat on the overrun tho :)

Assuming you've got a freer flowing exhaust in general to a std one, then eya, it will like being ragged more :D

smokeybone
27-04-2010, 21:09
well toke the williams out for a little bit of a thrashing last night only for it to brake down.

Had a look today and it has rubbed through one of the fuel pipes by the timing belt cover, So lucky the bloody thing didnt catch fire, what a stupid design running the fuel pipes where they are.

Car did seem to go a bit better higher up the rev range with the decat, but think i prefer the low down grunt coming out of the corners tho

Wobba
27-04-2010, 21:27
Mate, it IS a shit design. There is supposed to be a plastic fuel line protector...but guess what happens to them after 15 years...

http://i174.photobucket.com/albums/w102/barneywobba/My%2016V/DSC00259.jpg

Yea, they wear the fuk out.

Best bet, replace damaged lines (quite easy) and route them higher up and cable tie them away from the aux pulley.

smokeybone
27-04-2010, 22:09
Changed the fuel line all the way back down to the underneath, and cable tied it to the little pipe that is bolted to the timing cover going to the map sensor.

Do you think it would be worth putting it through some hard plastic pipe or something, as im a bit nervous after seeing that today

Wobba
27-04-2010, 22:29
Nah as long as it is kept away from the pulley, you're fine.