burt2000

iTrader: (1)

my insurance wont cover a complete decat, i already have the middle one out on my 1999 uk classic i wanted to go for a full decated downpipe but technically that will mean my insurance is void so i was gonna get a 100 cell sports cat instead, just had a few q's

Is the difference in power noticeable or only a few bhp? and

Does it still give a bit of an increase in noise and that fuelly smell after a bit of a thrashing rather than the manky sulphur smell from a normal cat

any answers very much appreciated

Barry

funkyspider

Firstly you have no choice if you want to free up exhaust flow by removing down/up pipe cats lol

I think Prodrive quote a 2% loss for their PPP downpipe over fully decat so pretty unnoticable at moderate tuning levels really (above 300ish it might start to throttle the map a bit I suspect. I think 911 removed his sports cat, but if I remember rightly that was a competition hill climbing car).

I've not noticed any smell other than hot brakes and overfuelling after I've 'driven' mine - Oh and sometimes the smell of fear !

There is a slight increase in noise - more 'throaty' if you like, The prodrive sports cat is the only one on my car - and passed MOT this week with no bother.

You could always decat the downpipe and leave the centre on (I hope you didnt throw it away). This is the least restrictive of the standard cats and should pass MOT assuming it's working correctly, you haven't overfuelled it and burnt it to death and you get it hot enough for the test

My car is MY01 bugeye, so if yours is a classic then I don't know if PPP sports cat is available ?

Dill_typeR

I though classics only had one cat, in the DP? Mine is an earlier model though,'97', so may be different.

As above, H+S (like prodrive) also claim a 2% loss with a sports cat over a full decat. Mine is fitted for track use, and I have noticed no smells from it, it didn't smell of sulphur before either, but I've been in other cars (mates nissan) that do.

burt2000

iTrader: (1)

i bought he car with a magnex on it from a dealer and the centre section was already taken out so i cant get it back, suppose im gonna have to go for a sports cat even thought they are really expensive!

andythejock01wrx

I have sportscat as only cat on my 01 WRX too and i reckon it's the dogs danglies. Apparently not significantly slower than full decat.

£289.99 at API, cheaper 2nd hand !

briforbes

I have a zerosports 3" downpipe with 100cel sports cat in it. I had the car mapped by Andy Forrest on Tuesday using an a'pexi power fc, and he commented that there may be an extra 5 odd bhp available if I were to swap to a de-cat and a less restrictive exhaust (downpipe back is a 3" blitz nur rx, which has a reduction in the rear can to keep noise down), as the exhaust was strangling it slightly at the top end.

For the sake of 5bhp - I'd rather keep the neighbours, police and mot tester happy. The car feels stupidly quick now anyway (circa 330bhp at 1.35bar) so I doubt the extra would make much difference. I'm very happy with it as it is.

911

I have made a science of this topic...

I did indeed fit a very expensive H&S 100 cell 3'' d/p to my previously decat road/hillclimber.
It cost £400 + £40 to wrap it.
The claim is a loss of 2 bhp. Maybe on a stock low reving car, but not on my Sti.
The top end is blunted considerably and you can certainly feel it.

It was on for 450 miles or so and 3 competition weekends.

I now have an API decat, 3'' through which was an astoundingly good fit, and the engine is now back to it's old sparkel when AndyF mapped it.

On the road only, you tend not to notice as you don't drive a lot at WOT, but I will save the H&S for the MoT.

Graham.

burt2000

iTrader: (1)

sounds like the difference will not be hugely noticable between the two then, just wondering if a sports cat will make a noticeable difference now over the standard downpipe on the car...in the future i plan to go for FE TD05, walbro 255l pump with a rising rate FPR and a greedy profec b boost controller. I would be happy with a genuine 300bhp out of the car hopefully those mods will get me to it or even slightly above

H&S downpipe with sports cat is £580!! any cheaper alternatives i never see them come up 2nd hand unfortunately

911

I managed a special deal on the H&S but the results are there (subjectivly) for me.
My Sti is around 360 bhp.

Scott.T

iTrader: (2)

I found similar things to 911.
On a 300BHP UK Turbo I could feel the difference. Plus it changed the exhaust note which I took an age to get how I liked.
Thankfully the ebayer that bought my decat understood, when I decided he couldn't have it as I was putting it back on

burt2000

iTrader: (1)

id much prefer the full decat if only greenlight covered me with it on :-(