924Board.org

kye · Posted: Thu Dec 02, 2004 1:25 pm Post subject: is a WRX exhaust an upgrade?

hi guys.. back to pick the collective wisdom!

thanks to a friend I now have a couple of brand new WRX exhausts in my front yard and was wondering if they're an upgrade to the original exhaust on my 81 ROW turbo?

I presume they're from the normal WRX, although i'm not sure of any differences between the exhaust on the STI or the normal WRX.

I haven't looked to see how well they'd fit, but on initial inspection they don't look impossible.

anyone ever done it? or know what they're like?
I have a feeling that porsche will have optimised the exhaust for the right back pressure etc, but if it's an upgrade, then i'm in!
_________________
it's funny, but when they said "Anything is Possible", that's exactly what they meant....

Lizard · Posted: Fri Dec 03, 2004 2:32 pm Post subject:

on a 931 the least amount of exhaust restriction the better!
_________________
3 928s,

kye · Posted: Sun Dec 05, 2004 12:15 pm Post subject:

thanks lizard, I thought that might be the case..

I am thinking that to see if there's any gains to be made from my exhaust I might have to do a test run by removing it and going for a drive with no exhaust.
if there's no improvement there, then my exhaust isn't getting in the way of anything, and isn't being a flow restriction or anything.

of course, i'll also have to make sure I don't get pulled over, as the car would be quite loud!
_________________
it's funny, but when they said "Anything is Possible", that's exactly what they meant....

My924gtc · Joined: 14 Aug 2004 Posts: 1362 Location: 248

I'd say sell those two WRX exhausts on ebay and fund the purchase (at least part of it) of a 944 system if you want to upgrade. Maybe even a B&B system? I'd think that would be easier than trying to make the others work.

Just my $.02 really.
_________________
MJ
'81 924 2.0L T
'82 924 2.3L SC/EFI <---online fall '06

Sponsor of the 944 Cup and Super Cup
Sponsor of the "2006 Battle in the Badlands"

Lizard · Posted: Sun Dec 05, 2004 3:21 pm Post subject:

the best thing you can do for the 931 exhaust is to just or better yet remove the cat, the factory muffler doesnt flow that bad so you should have to worry about it, I wouldnt run with no exhast on the car as then the exhaust will pool up under the car.

iirc they have also found that part of the thing that assists turbos in producing boost is having the backside of the exhaust fins having a much cooled zone than the manifold side, so if you want to get boost abit quicker you may be able to ceramic coat, or wrap with header tape the manifold and exhaust housing of the turbo, and then on the pipe right off the turbo to weld on some heat fins to assist in head dissapation right after the turbo.
_________________
3 928s,

kye · Posted: Mon Dec 06, 2004 3:09 pm Post subject:

I don't own the exhausts, they're a "take what you can use and give the rest back" type deal I think.. a friend is into salvage and finds all kinds of crazy things!

it's good to know the factory muffler flows well, as an alternative the WRX ones are HUGE!

cool wrt removing the cat and wrapping pre-turbo and cooling post-turbo.. that'd make a larger pressure difference, thus give more flow at that point.
i'll have to put it up on the ramps and see what it looks like to work on.

I can slowly feel the need to buy a welder of some sort, although i'll try and hold out if I can..

_________________
it's funny, but when they said "Anything is Possible", that's exactly what they meant....

Khal · Posted: Mon Dec 06, 2004 4:24 pm Post subject:

I could be wrong... but I thought we don't have catalytic converters on our Turbos?
_________________
'80 924 Turbo

Lizard · Posted: Mon Dec 06, 2004 4:52 pm Post subject:

Khal, you would be VERY lucky if you didnt, but I thought that only 79 ROW didnt come with cats and Lambda systems, but i could very well be wrong, if you take a pic of where the wastegate pipe returns to the main exhaust pipe I will tell you right away if you have a cat or not.
_________________
3 928s,

Khal · Posted: Tue Dec 07, 2004 6:37 am Post subject:

Yeah, I'll try to get a pic. I'm outta town at the moment -I'm in sunny Melbourne again

(it's raining) Won't be home 'til next week.

I've got a modified exhaust anyway. So mine may not give conclusive proof...
_________________
'80 924 Turbo

Carris · Posted: Tue Dec 07, 2004 8:31 am Post subject:

There are no cats on Australian 924's, they ran on leaded petrol you can't use a cat.
_________________
Chris