Help Info reqd ref 05 WRX exhaust components and PPP exhaust changes

[arch]

Guys looking for some info. If I am correct my 05 WRX exhaust is currently made up of a turbo down pipe, front cat, centre silencer and back box.

Is there also a cat in the turbo up pipe as has been suggested to me?

 What exhaust parts are replaced in the WRX PPP. I know the back box is replaced and the turbo down pipe is replaced with the sports cat but what happens to the front cat and centre silencer.

 I already have a Prodrive back box but have been offered a sports cat and section behind sports cat from a 05 STI. I assume the sports cat will fit my WRX

but is the section to the rear of the sports cat any different to that already fitted to my WRX, it certainly doesnt look any different. What other exhaust parts

would I require to complete the parts as fitted to the WRX exhaust aspects of PPP. I also note that Prodrive sell a decat pipe for the section behind the sports

cat which is housed within the standard heat shield and is available with a resonator or without. Is this part of the PPP.

Also would I be correct in assuming that the STI has only 2 cats fitted as opposed to 3 on the WRX, if so is the 3rd one the one in the turbo up pipe?

 thanks.

[st3ph3n]

For reference the new age exhaust goes up - turbo - down - cat pipe - centre section - backbox. 

Standard new age WRX has 3 cats - up, down and cat pipe. STI has 2 - down and cat pipe.

PPP on the WRX is a high flow IC hose, removal of the 3rd cat and the replacement backbox. With the replacement ECU too obviously. The other 2 cats remain the same.

PPP on an STI includes a high flow DP cat, 3rd cat delete, backbox, a fuel pump and the ECU too.

If your car is an 05WRX with PPP then it will have 2 cats - up and down, the 3rd cat is deleted with the PPP part (not sure if it is resonated or not), you then have a standard resonated centre section and finally the PPP backbox.

 

[arch]

Cheers for the info wasnt sure about the STI but there is more of a difference than I thought.

I currently have a standard 05 WRX appart from the Prodrive BB. My intention is to fit the Prodrive STI Sports cat down pipe, 3rd cat removal pipe leave the centre section and retain the Prodrive BB. Also fit the High Flow IC hose and have the standard ecu remapped. I am of course assuming that this should all bolt directly on. Not sure what gains this will give me along with a panel filter but not really looking for any massive gains anything up around the PPP figures would be ideal but obviously a lot would depend on what I want from the Map.

[st3ph3n]

Well I have an 05 WRX and I have the up and down pipe cats still in place, a 3rd cat delete (got from Gus the bus on here, his mate makes them), a de-resonated centre section and a h+s backbox. With those mods it made 250bhp and 232lb/ft of torque. That was without getting any remap. It was run at crail against some 05 WRXs with PPP and it faired VERY well.

Since it was on the rollers it has had the high flow IC hose fitted but nothing else and it does feel just that wee bit quicker with that too. 

All of these things are bolt on and off as you say. The car could be put back to standard exhuast wise in 30 minutes I imagine.

If you're going to go with the high flow DP then replace the up pipe with an STI one too. Will cost you £50-70 for one plus fitting.

Numbers wise - you'll see over PPP. Removing the resonated centre will make it even better, but it does increase the noise. 

[jimser]

ive got a 3rd cat delete pipe and unresonated centre section coming off my car shortly if your interested.only covered

5000 miles

[arch]

Thanks for the help guys. I have picked up the Pro drive sports cat and the prodrive 3rd cat delete pipe for £180 off an 05 STI fitted from new so not that old and looks in good nic. I think this is not a bad deal.

The only thing is the sports cat does not have the heat blanket fitted is this necessary, I am assuming its function is to protect anything near the cat from the heat and are the heat blankets easy to pick up. Was thinking of leaving the centre box in place at the minute as I use the car daily and dont really want to increase the noise to much, is this centre box highly restrictive. Are there any issues with replacing the down pipe and removing the 3rd cat without a remap?

Cheers guys appreciate the help, said I would leave the car as standard but looks llike I lied.

[]

[gus the bus]

The Sti Prodrive Downpipe sports cat is a bugger to fit on a WRX[] I believe Cal has tried and I've tried too and gave up in the end.

You would be best going for the cat pipe and deresonated centre section IMHO. The centre section doesnt really increase noise with the Prodrive Backbox just the tone gives it a nice deep tone[Y] 

what Jimser is selling would be ideal if you aint bought the Sti stuff already.

No remaps required with those changes[Y]

Hope this helps

Gus 

 

[arch]

Gus

Thanks for the info, I have already arranged to buy the Sports Cat and 3rd cat removal pipe so not now prepared to mess the guy concerned about. I assume access is the problem. Can it be done from underneath with car on ramps. 

If it is a pig to change I assume it is loose nuts and bolts and not bolts into a threaded flange or is it purely access to the bolts. I assume you need to remap if I change the downpipe but not by removing the 3rd cat and straight through centre section? What gains would be reasonable to expect with

 a) ProdriveSports Cat, 3rd cat removal, centre section left in place, Prodrive back box.

3rd cat removal, centre section straight through pipe and prodrive back box.

c) a and b with high flow intercooler pipe from PPP.

 

[~ ~ Cal ~~]

Gus

Thanks for the info, I have already arranged to buy the Sports Cat and 3rd cat removal pipe so not now prepared to mess the guy concerned about. I assume access is the problem. Can it be done from underneath with car on ramps. 

If it is a pig to change I assume it is loose nuts and bolts and not bolts into a threaded flange or is it purely access to the bolts. I assume you need to remap if I change the downpipe but not by removing the 3rd cat and straight through centre section? What gains would be reasonable to expect with

 a) ProdriveSports Cat, 3rd cat removal, centre section left in place, Prodrive back box.

3rd cat removal, centre section straight through pipe and prodrive back box.

c) a and b with high flow intercooler pipe from PPP.

Hi Arch

I tried doing what you propose like Gus said - hangers are different and foul the car & the flanges don't perfectly align. Ask AWD in Perth

changing the downpipe is easy...............if you have done it a good few times and learned the hard way. Easier on a newer car though but still a risk of shearing a bolt on the turbo

a) 260 bhp

240 bhp or so

c) 260 bhp or so with less risk of the rank standard IC hose going belly up. The new IC hose can take higher boost and yileds smoother air flow

I did a thread while back on my exploits with dyno results but alas the forum search function is not what it ought to be. I will try to find it though

Cheers

Cal

[~ ~ Cal ~~]

I will try to find it though

Cheers

Cal

 

Voila :- here's the post from way back in September ................. bear in mind that a PPP highflow cat is not 100 CEL

I still get playful pelters for claiming the car to be a STi killer but my videos from KH don't lie. STi10 with 2.5 Litre engine was dispatched on two occasions although I know the track well. Numerous other weapons dealt with too but the track varied from damp to sodden !

Cheers

Cal

*********************************************************

The background

My goal has been to slowly mod my car and create a daily runner which has a reasonable combination of  power mods, chassis tweaks and powerful brakes which can handle the odd track day. My suspension is untouched as yet but the brakes have been fettled and are more than adequate for track and road in their current state. So Whiteline gear to follow me finks. The aspiration is to hone my car into a reliable all-rounder B-road weapon which can extract the odd STi scalp ( if required). Of course the STi ( say a 2002 UK model for arguments sake) has many different features other than the 6 speed box, stronger brakes & better handling but I like the thought of issuing a small fright on occasion. Apparently the STi UK 2002 model had 261.5bhp at 6,000rpm and at 253 lb ft at 4000 rpm.

Anyway, purpose of the post is to show how a few tweaks can dramatically transform a 215 bhp standard UK WRX into something a bit tastier.

 

3 graphs on each page represent the 3 different dyno sessions I have had at Wallace Performance ( Dastek system) over 3 different stages of tune over 12 months or so ( I kept using the same dyno set-up for consistencies sake despite having no control over weather etc !)

Stage 1 - the usual attempts to let her breathe and free up some burble.

Factory Map + K&N panel filter, WR Sport backbox, ScoobySport decat link pipe and unsilenced centre section. Horrible standard WRX downpipe & up-pipe cat still in-situ.

Stage 2 - a remap to see what gains can be realised from a Ecutek remap

Andy Forrest Map + the above

Stage 3  - more serious tweaks in pursuit of more boost & ponies

Revised Andy Forrest Map + ScoobySport Backbox mated to to complete turbo back TSL Thundercat system ( high flow 100 cell cat) +  decat H&S up-pipe + ported turbo ( though still a standard TD04). Not hitting target boost in 2nd as I need to tweak the actuator but 3rd & 4th is hitting 1.2 bar of boost.

The results

(I know the real indicator is how it feels on the road but the below is a worthwhile exercise to superimpose the three runs)

In summary,

I have a nice quick spool up with torque flooding in early & strong ( above is 4th gear on all runs (I believe)) with peak torque almost delivered at only 3500 rpm. Bottom line is 280 bhp @ 5750 rpm and 265 ft.lbs @ 5200 rpm. [H]

Any thoughts

 ..as to what should come next ( TD04 hybrid perhaps plus larger IC ?) Not really keen on going beyond 300 bhp in line with my reliability mindset.  Handling recommendations also welcome - not keen on the brutal drop of Teins but Eibachs may be next. However, the standard springs are excellent on a bumpy B-road so maybe Whiteline gear alone may prove the remedy ?

 

Cheers

Cal

p.s here is the car in question :-

[thewelsho]

ive got a 3rd cat delete pipe and unresonated centre section coming off my car shortly if your interested.only covered

5000 miles

What car do you have? Might be interested in the Cat delete pipe.

[~ ~ Cal ~~]

Arch - have a snifter in here for some info too :-

http://www.rallyperformance.com/engine.shtml

Cal

[gus the bus]

ive got a 3rd cat delete pipe and unresonated centre section coming off my car shortly if your interested.only covered

5000 miles

What car do you have? Might be interested in the Cat delete pipe.

Not the one for you John[] like mine its a blobeye.So, as we know it dont fit!!!!

[arch]

Guys really do appreciate the advice. Is it a case that it really does not fit or will the flanges line up if used with the prodrive 3rd cat delete pipe.

I am working on the assumption that what you found was that when u fitted the sports cat to the turbo if the flange mated square the mounting brackets would foul the car and not line up with the factory mounting points is this a fair assessment of the problem. Has anyone managed to fit this to a blobeye WRX or is it just a case of forget it. Could it be that the sports cats are slightly different for the 05 and onwards as the newer sports cats seem to come without the heat blanket so could there be a slight difference with the cats - probably clutching at straws here. [:'(]

 

[Turbo-uk]

arch , I touch goats