Just got back today from the shop with my new FM40 true duals! YIPEE! They ARE loud I'll tell ya. Tonight, on the way home, I actually saw a couple of teenagers turn their heads to look. I admit, sadly, that I think that I might have lost some (albeit very minimal) off the low end, but it seems as though the whole damn system is running better now.

So, from the get go, the pick-up speed seems a bit slower, but once I'm rolling I seem to have more? Does this make sense? Or is this what most mean by losing some low end torque?


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Defacto,
I am glad to hear that you purchased a new set of 40 series Flowmasters. I also have a set on my truck, although they are a single in and dual out. I have also noticed a minimal loss of low end power too, so I have ordered a Flowmaster Y Collector (Y pipe) from Jeg's High Performance. It only cost me 37.99+shipping. Not a bad deal, and I've heard that it will bring your performance and gas mileage back to normal. Just a thought for you, enjoy your new Flowmasters.

Rabbit

 

I can't put on a "y" with true duals, only an "H" pipe can be added; but I've noticed that my mileage is way better than is was previously. As soon as I've had a couple of tanks, I'll do the math (I want a mix of highway and city), but all I can say is I'm happy as hell with the setup, now it sounds like a truck.

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Black 98 F150-XL, 2WD, 4.6L Slappin Windsor Triton, 5spd.,
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Triton V8 Badges, Duraliner Bedliner, K&N, Ziebart, Castrol Syntec
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Defacto, how much did the setup cost you? I'm thinking of putting in a new muffler. The stock exhaust note for '01 F150 HDS is too soft for my liking. Mind you, I don't need to shake the building down but a bit more muscular sound would be nice. I haven't yet looked under the truck, but I'm pretty sure it's a single pipe off a Y pipe going to a dual out muffler. Maybe I can go to dual-in/dual-out setup with a H pipe...

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Early 90's Ford Probe -- mods: stereo stolen to reduce total weight. Speed gain negligible, unfortunately.
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I just had my 50 series installed today, $270 for pipies,tips(2) and "Y". Sound is great, I did not go 40 because I wanted the "mellow" sound. But you can definitely tell its louder just not obnoxious.

 

What about the Delta Flow FM40s? Are those considerably quieter than the regular 40s? Im looking for a mean sound but not so that it drones in the cab.

 

Beach Cruiser- Yes, the DFs are quieter. You can see sound graphs on all FM mufflers at their website. If you want a "mean sound", you have to get loud mufflers on these trucks due to the multi-cat setup. The REGS sound good, but many have posted slight reductions in low-end torque and drone.

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Max, you're right on the money with that one; I'm not 100% sure, but I it feels like I've shaved a bit off the low end, but I do know that I pick it up again in the mid and higher ranges. So it seems that I've picked up a few horses, but lost some torque.

On the highway is the only time I get any drone in the cab, and I don't really notice it unless I'm on a long drive. But for those who are particularly sensitive to this possibility, they should stick to the FM 50's or go with the Ravins (which are both fine setups)

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Black 98 F150-XL, 2WD, 4.6L Slappin Windsor Triton, 5spd.,
RegCab, Short WB, 3.08 rear, Air, Rear Slider, FM40 True Duals
Triton V8 Badges, Duraliner Bedliner, K&N, Ziebart, Castrol Syntec
HAWK Plus Bedcap, profile+ wrap-around bug deflector,
Blazer Neon-Blue projector fogs, custom look'n door cracks
Tinting: #4 RearCab & Bedcap Windows, #2 Cabside Windows

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