I think I will try to sell them here...

The reason is when you install AWE Cats & Mufflers b/c of Scavenging you end up loosing some low-end Torque over the stock set up. And when you add the X51 Headers on top of this set up, it gets even worse.

Since the X51 Headers are short-tube and large diameter headers they are built for the purpose of giving you power in the high RPM range at the sacrifice of the low end.

Equal length headers on the other hand are designed to give you low end power at the sacrifice of high end.

My car is a DD, so I need low end power more than high. Also I do not believe that mixing and matching different exhausts is the right idea to get the best results since each manufacturer uses different pipe diameter...

 

Thanks, good info. I'll definitely keep that in mind.

 

I agree.

I used 996 x51 headers on my 00 996 with fabspeed mufflers. I could actually notice a difference both in power and sound. Comparing to other 996's with just fabspeed mufflers there was still a difference. I am a big beleiver of the x51 header. I personally would choose x51 header over an aftermarket header.

 

Is there really a difference in software? I have read a lot and it seems GIAC is a really good choice, but others are mentioned more. Are they all very similar really?

 

What software, I didn't write anything about any software in my last comment

 

You didn't, but I wanted to find out people's opinion of the various software available. I didn't mean to confuse. I should have just added my comment without quoting you.

 

Is there really a difference in software? I have read a lot and it seems GIAC is a really good choice, but others are mentioned more.

 

Ah ok

I have no idea about the software part of the tuning process to be honest...

 

Watching this thread as well, since I have a PSE and looking into the AWE cats. Question is whether to use the cost effective X51 headers or spring for the AWE or CarGraphic headers.

Thoughts?

 

I would go with X51 or the AWE. x51 are short runners. Awe are equal length. It all depends on where you want your torque curve.

 

Any diameter matching issues going with the X51 to the AWE Cats? Sharkwerks is local so I will have them do the tune.

 

Should not have a problem using x51 headers with AWE cats. I beleive AWE cats are designed to work with stock manifolds. I would check with AWE to be sure but I think you will be ok.

 

I had X51 headers w/ AWE Cats, no problems with it... As duane said, where do you want your torque? This is an important question. Figure this out first before making the move on the headers. Talk to the guys @ SharkWerks, they'll explain everything

 

Thanks much, will check with AWE to be sure.

 

Understood and agreed on the torque curve outlook. I tend to like shifting it to the upper end but that's a habit based on tuning Saabs with weak transmissions, but the 997 may see track duty only a handful of times in its lifetime, plus the X51 seems to represent good value.