IW STi Forum banner

1 - 5 of 5 Posts

·
Registered
Joined
·
1,558 Posts
Discussion Starter #1
Quick question.

I want to post about GD and GR CBEs. Where should I post? I'll be referencing both GD-specific and GR-specific hardware, a dyno chart, and other information. I also want to welcome discussion about power gains (most people think that there are no power gains with CBEs but Nameless just posted some interesting results to their FB page). Basically, it'll be a general-like posting of exhausts, but in relation to both the GD and GR.

I'd like to post in General but I know that mods and members hate it when someone just drops posts there without thought. Granted, I'm thinking that's the best place for my post, since it's not specific to either generation of car. And I don't want to be yelled at, ridiculed, or given points for not following guidelines. So I thought I'd ask.

Per the General header:

Please visit the FAQ/Newbie Forum before posting in the General Community Forum, which is reserved for discussion of general things related to Subaru that do not fit in other specific forums. If your post is not related to Subaru please post in Off-Topic. If your thread is related to the 2003/4-2007 STI (known as the GD model) or the 2008+ STI (known as the GR model), please follow one of the two links below to post a topic in or to view those forums. Please do not post such topics here.​

My post will not be newbie-related, and I didn't see anything similar within a FAQ that helped me (plus, I want to share information).

So, where should I post?
 

·
Registered
Joined
·
1,558 Posts
Discussion Starter #3 (Edited)
Kevin,

It would be something similar to the below:

So, I monitor Nameless Performance's FB page and today, they did a dyno run of a GD WRX ('05) with their catback exhaust...they gained 29 ft/lb peak torque, with a 20 ft/lb average across the power band!! With just the catback and no tune.

That is crazy.

Now, everyone on the WRX/STI forums swear that CBEs don't add much performance, but 29 ft/lb is about as in-your-face as you can get. And they've a dyno chart as well. This means that the claim of CBEs on WRXs and STIs not giving any significant gains is a crock of crap, or that the vendor isn't telling the full truth...I don't know. I know that turbocharged cars respond well to little to no back pressure (unlike naturally aspirated cars) and that they can make respond favorably with 3" CBE piping, but that's a very large gain, for something as miniscule as a CBE mod. Maybe the stock piping is extremely restrictive? I'd thought the downpipe was the main restrictor, though. Or, maybe it's not that it's a restrictor, but maybe because a free-flowing downpipe can affect air flow (does that even sound right?)?

I already have the Nameless axleback muffler delete exhausts. I wanted it for the sound more than any power gains, but if they got 29 ft/lb on a '05 WRX with just a CBE, I wondered what the GRs ('08+) would gain. I asked Jason at Nameless and he stated, "32ft lb and 22hp on 11 CBE's." I'm not sure if that's for a WRX or STI, but that's just plain ridiculous (in a good way) for a CBE...and just think, they haven't even touched the downpipe yet.

This is good for me, because I'm trying not to do any engine mods that warrant a tune...that's not an option for me. I'll start investigating what I need to meet the CBE specification...I probably just need the midpipe, but may need to get the muffler replacements instead of the axleback, because I've a friend that said his car was too loud with the Nameless midpipe and axleback muffler deletes.

There's one worry, though...with that much torque gain, you'd think that a tune would be mandatory. Nameless is shooting for 70 ft/lb of torque on just a turbo-back exhaust. That may seem like a lot, but they're almost halfway there already. They gained almost half of what they'd get with a TBE, but with no tune? The real bottleneck of the exhaust is the stock downpipe, but if they're getting that much torque from just a CBE, that means the downpipe isn't necessarily the only bottleneck...maybe two bottlenecks are worst than just one? I'm just trying to understand how they got that gain without a tune being required.​

I think that type of gain is awesome and wanted to share it with the forum, in case no one was aware (I did ask Jason to share his data with IWSTI but I haven't seen him post today). Also, as I state at the end of the above, I want to be sure that a tune isn't mandatory, even if Jason says it isn't.
 

·
Registered
Joined
·
5,630 Posts
Does he have more info on each run? Were the runs done the same day? Back to back? What was the temp? Same conditions for each run? Etc.
 
1 - 5 of 5 Posts
Top