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Discussion Starter #1
Hey guys, just have a few questions that some of you Solo guys may have some incite!

I am getting ready to pull the trigger on a cat-back system. I am really considering a Solo system and get headers a little bit down the road.

NOW my question is there is two options for the solo set-up.

The 3" or 2.5". the 3" requires you go get headers right away where the 2.5" is a bolt on to our stock set-up.

The thing is I am looking to supercharge her in about a year or so. If I do just get the 2.5" will that be adequate to be able to flow 650ish HP down the road?

ORR should I just bite the bullet and get the 3" with headers and then I will need to tune it as well. Just money I don't really have to spend at this very moment.

Any advise would be great, thanks a lot guys!
 

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2.5" is plenty for what your goals are. But there are a few ways to go about this.

1. You could go Full 3"/ headers Tune Now. And when you do your supercharger save a little extra for a OTS or Custom Cut Blower cam to maximize gains (at which point you'll need to 2nd retune anyway) OR

2. Do 2.5" now, save for heades blower (blower cam still optional) and once you have EVERYTHING READY install it all in one shot and tune it once.

*is there a converter in your future as well? (something to think about)
 

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Discussion Starter #4
Thank you for the advise Eight, if I am certain the 2.5" will be good down the road for the HP I will be pushing that that is exactly what I will do. Does anyone else want to chime in on this as well, the more advise the better before I throw down the money at the end of the week for this.

Thanks again man!
 

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dual 2.5 = 512hp
dual 3.0 = 739hp

After the read, even in not fully digested, something is gained.
 

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Also. With a 3 inch tip , you'll need a gxp diffuser. Unless you are already in a gxp lol. Otherwise you'll melt the diffuser.
 

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Discussion Starter #9
I did actually order the GXP diffuser today to fit the big tips :), so if that math is correct there is no one running over 512hp with a dual 2.5" set-up? That is a lot of reading material, I do appreciate it but I am just mainly looking for a main census of what people think. Would I theoretically be able to run 650hp with the 2.5" solo set-up?
 

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Beware. There is what people think and there is data. Data typically wins.

The numbers calculated, not thought, are good approximation at which point the exhaust will have a negative impact.

Can you run smaller? Sure, many do. In fact, I'm on 2.5 and should be at 3.

You asked about the size, now you know. What you do with the info is your decision.
 

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Yes, LSA with BTR2 cam.
FWIW, kook mids, 2.5 mid pipe, magnaflow muffled x, vibrant resonators and dynomax vt's.

That typed, if I had read that paper before, I would be at 3", including opening up the collectors. I like the system as is and with traction being the challenge it is, moving to 3" is not worth it (to me).
 

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Definitely a good read. I'll be going over it again for more clarity.

If you're looking to make the hp you're talking about then I'd have to lean towards the 3 inch exhaust. I think the important question is are you talking rwhp or hp at the flywheel?
 

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Definitely a good read. I'll be going over it again for more clarity.

If you're looking to make the hp you're talking about then I'd have to lean towards the 3 inch exhaust. I think the important question is are you talking rwhp or hp at the flywheel?
I was assuming OP was talking Crank HP. 600+ to the tire means he's got to prioritize his build and the exhaust aint at the top of that list (at least not for me anyway) suspension work, possibly a little tranny work (although not required) fuel pump swap at minimum.. The crank in this car is good for what 700ish? Than theres considering refreshing or building/stroking the short block but you cant forget a little head work while their off.....damn see how fast that escalated? Lol

I myself have a goal of 700ish to the tire eventually... Baby steps, do it once do it right.
 

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It's much easier to do the whole exhaust at once. Getting the headers down the road requires cutting or adapting the fit. Get the whole thing with headers and install it yourself. This was the easiest exhaust I have personally done. Mine is the 2.5 with hiflow cats designed to connect directly to Kooks long tubes. Beautiful sounding system. I have the 3" with hiflows on my wife's Mustang. It is outrageously loud. The mustang has a 1500 rpm cold start. This is guaranteed to wake the neighbours.
 

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I had that same exhaust on my mustang and loved it!

OP if you do the 3" set up and headers expect it to be LOUD!

I was in the same boat as you. I wanted some sound now and then I'll do headers, intake, tune etc. later. (I'm out of mod money for now)

I ended up just doing the Solo axle back (just installed it yesterday) then later I'm going with the Kooks OBX knock off set up (best bang for the buck IMO). It will bolt right up and I can then just cut and clamp a 3" magnaflow or the like in the tunnel area.
No, it's not going to be 3" all the way back but I'm fine with that, I don't think its going to make much of a difference on a stock block. It's a big hit to due it all at once because you not only have to do the exhaust but you need the tune at the same time.

I chose do up the suspension first so I have to segment the power stuff in stages.
 
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