downpipes and cat-backs

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May 14, 2005 | 09:48 PM

smokin_6.0

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downpipes and cat-backs

I'm shopping for a 4" exhaust for my 6.0 and was wondering if i buy a cat-back system can i later buy a downpipe to go with it?? I guess what im asking is does the downpipe go to the cats or is there a section of pipe between the end of the downpipe and the cats?

May 14, 2005 | 11:29 PM

4x4Mark

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From: Colorado Springs

yes, you can add a cat-back now, and then when you choose, add an aftermarket down-pipe of your choosing. I have the cat-back, and don't see a need to go beyond this - works great.

Mark

May 15, 2005 | 04:53 AM

HeavyAssault

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From: Gulf Coast, FL

Save some cash, cut the muffler out, weld in some 3.5" pipe, buy a MBRP 3.5" down pipe and enjoy the extra cash. To get a 4" to fit you will need to bend the firewall pinch weld area so it won't rub.

I have found that the new DP shifted my low end power higher in the rpm band. I'm glad I didn't go to a 4". My cost about $200 total and I did it in the driveway.

May 15, 2005 | 09:05 AM

IB Tim

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From: 3rd Rock

Quote:

new DP shifted my low end power higher in the rpm band

Did you want that?

May 15, 2005 | 09:44 AM

dbross

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Would replacing the muffler with a 3.5 pipe lower egt's, help or hurt fuel mileage or change torque band with no other exhaust mods? I tow a 10,000 lb. race car hauler. 2005 F-250 stock except for scmt in tow safe and econo. I use power service (grey bottle).

May 15, 2005 | 09:55 AM

IB Tim

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From: 3rd Rock

IMO it will lower EGT's ...MPG just a bit better
For your use ...sounds like a good idea.

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May 15, 2005 | 11:27 AM

HeavyAssault

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From: Gulf Coast, FL

TIM: I knew from past experience that there could be a low end shift. I tend to drive around town quite a bit and after a few hundred miles I could feel the difference at take-off. I will say that as I drove the truck it wasn't as bad the first ride so it really isn't a big deal. Did I really want that? No, but then when I add a tuner that won't really be an issue any more. If you do both(DP & tuner) at the same time I doubt anyone really could tell the difference. I'm running a non-modded PCM so that's how I can tell the diference. Since he didn't discuss any power tuners I thought I should mention the difference I found after install.