Exhaust size and material?
 

I'm into the detailed planning stages for the turbo setup on my car. Setup is 99% sure going to be a T25 .48A/R with a BEGI manifold shooting for 220rwhp at 12psi. I'm trying to decide on the exhaust setup now. I'd like to stick with the BEGI theme and use one of their 2.5" (or are they all 2.75" now) DPs. I would love to use mild steel to do this, since it'll save me some money, but what's the word on stainless vs. mild? I'm willing to cough up the dough, but if it's not going to gain me much besides the bling factor (which I don't want under the hood) then I won't bother. The hundred bucks will pay for injectors, so I'd really prefer to save the cash.

Same question for the catback. The options are the Enthuza budget turbo or the standard turbo exhaust. One is mild steel, one is stainless steel. Again, is there a big advantage to SS vs. mild? I was leaning slightly towards the stainless here because I can get a 3" catback, but it's quite a price jump, $369 vs. $450.

Shameless plug: I am selling my BEGI divorced WG DP. It has >2k miles on it. It has a t25 flange :)

Edit: nvm, apparently the dp is different between the 1.8 and 1.6.....I dont see how.

The stainless will not shed as much heat into the surrounding components and will survive many more heat cycles before fatigue.

2.5 is fine. 3 is better.

stainless beyond the DP is not really worth it unless you live somewhere salty or corrosion prone. a good aluminized will last until you swap exhausts anyway ;)

if the DP is only 2.5, dont bother with a 3" cat back *shrug*

The 2 1/2" stainless with divorced wastegate is what I would get. Check with BEGI.

KMag

The only reason I got stainless is because I drive it year-round and they salt the roads up here. It does look great though, too.

even in salty areas a good aluminized steel will last over 5 years and at that point rust through at any welds first (can be patched up).

I am worried about heat with the T25 at 220rwhp. Sounds like I should look at a 2.5" SS Begi DP to a 2.5" aluminized catback. I don't think you can call Northern California a "salty" area, and no matter where I go for college the car won't be used in the snow.

northern california and 220 rwhp.... go mild steel on both. there's not that much heat in the dp. ask corky.

You won't "need" anything other than a nice mild steel dp. If you are interested in how it looks and the length of time it stays together, then stainless might be worth it. I myself use stainless on everything I can, within reason.
-Michael-

Yeah, most of your heat is in the manifold... mild should be groovy, even more so with a flex pipe.

Sweet. I plan to stick with the T25 through college and then perhaps upgrade 5-7 years down the road, so mild steel will be perfect. Thanks guys. :)

3" Stainless or don't do it at all.

CHA CHING!

he said cheap, T25 .48a/r and 220 rwhp. you want him to spool at idle and be broke? :)

lol...no kidding...

You can do a nice 3" stainless system under $300 if you shop well. Thats fucking cheap.