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You will get to see this sunday!

Hey the mustang is a big upgrade over the 4 banger camry you were rocking lol.

What are your impressions of the V6 stang? Think the G8 crowd that isn't modded should be worried?
 

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HFC's only on a 2009.5 GT produce 8hp/8tq. Given the stock pup cats detract 6hp/6tq when compared to the 2008-2009 model, you are talking 14hp/14tq untuned. They are somewhat crippled by the 2nd set of pup cats. CC007's results are somewhat out because the shop did his pulls in the wrong gear. The stock exhaust really isn't too restrictive past the cats/pupcats. The only other possible bottle neck is the rear mufflers, but I don't have definitive proof that this is the case. MGM GT on the board is running 11.6's on the stock exhaust. Let me clarify: He has DT LT's, and then he's stock until the mufflers where he replaced them with Magnaflow's.
That's odd- replacing the restrictive cats with HFC's up front when the exhaust is hottest (and therefore flowing the highest) would seem to me to make a >12-15HP difference in Pre-tune guise. The pup cats, which are much further downstream, are far enough from the engine for the gases to cool and it not being as much of a restrictive bottleneck.

I'm debating my '09.5 exhaust/mod course of action now and my goal is to achieve the greatest gains while keeping the car sounding as stock and drone-free as possible.

If anyone has done the Solo HFC's only with a tune and has any measurable data, dyno or track, I'm all ears.

Thanks!
 

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HFC's only on a 2009.5 GT produce 8hp/8tq. Given the stock pup cats detract 6hp/6tq when compared to the 2008-2009 model, you are talking 14hp/14tq untuned. They are somewhat crippled by the 2nd set of pup cats. CC007's results are somewhat out because the shop did his pulls in the wrong gear. The stock exhaust really isn't too restrictive past the cats/pupcats. The only other possible bottle neck is the rear mufflers, but I don't have definitive proof that this is the case. MGM GT on the board is running 11.6's on the stock exhaust. Let me clarify: He has DT LT's, and then he's stock until the mufflers where he replaced them with Magnaflow's.
I guess that's where they get the 355hp number for the newer models, compared to the 361 from the older models? If the older models don't have these cats, then they're already making more power than the '09.5s to begin with...so adding HFCs is more beneficial to them.
 

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is it worth just getting these cats, or going with headers?
i would still like to keep my warranty intact, and with the cats, i can do so. with headers, its pretty much bye bye
 

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is it worth just getting these cats, or going with headers?
i would still like to keep my warranty intact, and with the cats, i can do so. with headers, its pretty much bye bye
Well, if a thread with 764 posts in it doesn't "show you something" then I donno what will. There sure are a lot of people out there with the SOLO HF Cats, and all are quite impressed with them.

Cats are ~600/pair and net ~25-30hp with a tune that supports them. Headers are from 1200 and up (coated, etc) and net you about the same, give or take 5 hp.

Plus, you're right, when the dealership opens the hood and sees headers, they're automatically suspect of a "heavily modded car" for any warrantee claims that you need done. Cats can blend away for the most part.

You decide.
 

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Well, if a thread with 764 posts in it doesn't "show you something" then I donno what will. There sure are a lot of people out there with the SOLO HF Cats, and all are quite impressed with them.

Cats are ~600/pair and net ~25-30hp with a tune that supports them. Headers are from 1200 and up (coated, etc) and net you about the same, give or take 5 hp.

Plus, you're right, when the dealership opens the hood and sees headers, they're automatically suspect of a "heavily modded car" for any warrantee claims that you need done. Cats can blend away for the most part.

You decide.
Zepcom,

I like your style. :D

Looks like quality CAI, Tune and Solo HFC's is the ticket for me. Now it's just deciding on which brand/model of the first two mods I listed.

Oh well, back to the threads to get more informed/confused, LOL.
 

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Well, if a thread with 764 posts in it doesn't "show you something" then I donno what will. There sure are a lot of people out there with the SOLO HF Cats, and all are quite impressed with them.

Cats are ~600/pair and net ~25-30hp with a tune that supports them. Headers are from 1200 and up (coated, etc) and net you about the same, give or take 5 hp.

Plus, you're right, when the dealership opens the hood and sees headers, they're automatically suspect of a "heavily modded car" for any warrantee claims that you need done. Cats can blend away for the most part.

You decide.
I agree with you almost all the time Zepcom, but I would like to see something to back up these claims. The Kooks mid length headers get 25-30 hp and cost around the same as the Solo cats w/tune. The Kooks LT's get 40-45hp with tune. CC007's dyno runs were unfortunately in the wrong gear (3rd instead of 4th) so his numbers can't be used for comparison purposes. I actually think the 30 is way too high for just the cats or the Kooks mids. CAI, cats, catback and tune net around 55-59hp. The CAI and tune alone get 26-30hp. Add another 8-12 for the catback and the rest is the cats. Of course I admittedly have never seen a tune + cat only dyno with exception to the one done on a 09.5 which only netted 8-12hp and that was with a tune. The pup cats were responsible for robbing about 6hp. That brings it to 14-18hp without the 2nd set of pup cats on this particular dyno.

One thing I am certain of is the power from the cats is noticeable. I think they are an incredible value for the dollar and ease of installation compared with the kooks mids.
 

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I have to go with Virus on this one. The cost savings over headers is significant, plus the labor to install is much less, and you can run your stock wires without a problem. If you've ever had a car with headers, you will find that the temps are very hard on ignition leads. The cost of aftermarket wires is sort of an unseen cost once the headers are in place, and even they don't last forever.
Just my opinion, but it might benefit you to listen to a few with catbacks and HFC's again. Another option (if you want to remain stock) might ne to find someone with the exhaust (less the pup cats) and swap your stock exhaust out for that piece. It would look better than cutting the others out, and there must be some of them out there. Problem there is that they're large and heavy, and you'd need to find one close at hand.
You might be able to find the sound you're looking for. One thing for sure, the Solo systems don't drone.
 

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I agree with you almost all the time Zepcom, but I would like to see something to back up these claims. The Kooks mid length headers get 25-30 hp and cost around the same as the Solo cats w/tune. The Kooks LT's get 40-45hp with tune. CC007's dyno runs were unfortunately in the wrong gear (3rd instead of 4th) so his numbers can't be used for comparison purposes. I actually think the 30 is way too high for just the cats or the Kooks mids. CAI, cats, catback and tune net around 55-59hp. The CAI and tune alone get 26-30hp. Add another 8-12 for the catback and the rest is the cats. Of course I admittedly have never seen a tune + cat only dyno with exception to the one done on a 09.5 which only netted 8-12hp and that was with a tune. The pup cats were responsible for robbing about 6hp. That brings it to 14-18hp without the 2nd set of pup cats on this particular dyno.

One thing I am certain of is the power from the cats is noticeable. I think they are an incredible value for the dollar and ease of installation compared with the kooks mids.

Okay, I was just going on what I remember cc007's full dyno test post was on. I didn't realize that they did the dyno pulls in the wrong gear! :slap:

My car has never been on the dyno, so I'm just living vicariously through what others have posted as far as numbers. I know a buddy of mine just dropped $1400 for ARH ceramic coated headers.... a waste of money in my opinion considering it's more than twice the cost of SOLO HF cats for somewhat similar gains. When you put on headers INSTEAD of HF cats, do you get twice the gains for twice the price?

That was the point I was trying to make.
 

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From my personal experience, I could not be happier with the changes we made to our GXP's exhaust. We have Solo HFC's with the OEM pup cats removed. The rest of the exhaust system is stock. The sound speaks for itself. I would not want it any louder. You can hear the exhaust note while driving normally but it does not hamper conversation or create problems with the neighbors. At WOT... it's a whole different story.

Of course a Livernois Dyno Tune is the heart of it all..

Good luck on your upgrades!

jjw
 

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From my personal experience, I could not be happier with the changes we made to our GXP's exhaust. We have Solo HFC's with the OEM pup cats removed. The rest of the exhaust system is stock. The sound speaks for itself. I would not want it any louder. You can hear the exhaust note while driving normally but it does not hamper conversation or create problems with the neighbors. At WOT... it's a whole different story.

Of course a Livernois Dyno Tune is the heart of it all..

Good luck on your upgrades!

jjw
I wish I could hear how that sounds. Any vids
 

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Wow, the cat's really make a big difference even with the stock mufflers. I'm sure with the GT mufflers it would be much quieter. Sounds very good tho.
 

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The GXP was still fairly quiet until the OEM pup cats were removed...

jjw
 

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Okay, I was just going on what I remember cc007's full dyno test post was on. I didn't realize that they did the dyno pulls in the wrong gear! :slap:

My car has never been on the dyno, so I'm just living vicariously through what others have posted as far as numbers. I know a buddy of mine just dropped $1400 for ARH ceramic coated headers.... a waste of money in my opinion considering it's more than twice the cost of SOLO HF cats for somewhat similar gains. When you put on headers INSTEAD of HF cats, do you get twice the gains for twice the price?

That was the point I was trying to make.
The Kooks LT's are only $778, but they also don't have cats which most people have to have. Without them though, I would definitely say the added hp/tq gains were worth that small price difference. However, I would have to add the cats on top of that and there is no way in hell I'm dishing out that kind of money for such little gains. Our stock manifolds aren't too bad!
 

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The Kooks LT's are only $778, but they also don't have cats which most people have to have. Without them though, I would definitely say the added hp/tq gains were worth that small price difference. However, I would have to add the cats on top of that and there is no way in hell I'm dishing out that kind of money for such little gains. Our stock manifolds aren't too bad!
When doing LT headers shouldn't you get them coated or risk having an ultra hot engine bay, which leads to a heat soaked engine. After coating and having to have a tune vs the cats and not having to tune, unless you want optimal gains I still think the cats are a better value than headers for a bump in performance.

In all honesty I would like to see the gains of the cats with shorty headers. Shorty headers don't gain anything in terms of peak HP with stock cats, but with the solo's I'm curious to know what the results would be.
 

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Damn you Morris don't tempt me! Just remember If I get them I'm coming to your house to install 'em!
 

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When doing LT headers shouldn't you get them coated or risk having an ultra hot engine bay, which leads to a heat soaked engine. After coating and having to have a tune vs the cats and not having to tune, unless you want optimal gains I still think the cats are a better value than headers for a bump in performance.

In all honesty I would like to see the gains of the cats with shorty headers. Shorty headers don't gain anything in terms of peak HP with stock cats, but with the solo's I'm curious to know what the results would be.
I have the solo hf cats and jba shorties, but you have seen my dyno results.
 

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I remember that thread. Your dyno numbers were way off. I think Rick does that to all the VMS tuned cars on purpose lol.
 
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