I have a 04 scab 4x4 4.6. I have already got the windows tinted and the Air Raid MIT with a K&N filter. I have got some money to spend on my truck and I am considering tuner, magnaflow muffler (not complete catback), or underdrive pulleys. I can buy two of the three that I mentioned I just don't know what will be the best thing to get. I am not buying gears because it will be too expensive getting them replaced. I just want a little more power for normal everday driving. I don't race my truck, but would just like to have a little more power.

 

Magnaflow exhaust and tuner.

 

Any increase in mileage or performance with just a muffler?

 

hey 99 saw your post on more power: i also have a 4.6 and just replaced the muffler with a Raven mufler with 3"inlet and 3" single outlet with a kickdown. also replaced the air filter with K&N and i figure for a few hundred bucks i gained 10-15 hp.and as a side benifit got awsome sound from the raven.try this i don't think you will be dissapointed.let us know??

 

Several have just replaced the muffler and reported some gains, for sure power increase at the high end. I had a Magnaflow Catback put on mine, but I must admit, if I was doing it today, I would keep the pipe and just have them put a 'straight through' Magnaflow in place of the factory oil drum.

Tuner gives you the most feel for the money.

Best dollar for performance would be a straight through muffler and a K&N air filter. Do the whole deed for about 150-175.

I have had two different Magnaflow mufflers on mine, A K&N filter, a Superchips tuner, and a AEM intake with it's own 'K&N like' filter.

Mileage increases came from the exhaust, (1 on the highway, 0 in town)
K&N filter (.75-1.5 on the open road, .50-1 around town)
Exhaust (.75-1.25 open road, 0 around town)
Tonneau Cover (1.0-1.5 open road, .25-.50 around town)

That's months of logging lots of changes, checking with Scanguage, etc.

With Superchips set to 87 with the K&N, Catback, and tonneau I have been getting 22-24 higway at the speed limit (70) and 14.5-15.5 around town. Lousy driving condtions local.
4.6, reg cab

Don't wanna talk about the Brute Force, with the Superchips on Premium. Don't want to think about it. Lead foot, empty wallet.




If you like it fairly loud, but legal, Put the 18'' Magnflow in place of the factory muffler, and have it done by a pro shop.
The 18 was too loud on my regular cab. Great running, really great full throttle, but too loud when going up a long slow grade. Like the one I have to drive every day...
The 24 sound fine, not nasty, but good.

That's with the catback with a big tip.
So I figure the 18 with a stock tailpipe would be about right.
Chris

 

What is the part number for the 18 magnaflow and also for the raven muffler?

 

Hey Chris,
Speaking of which, how does the 4.6 respond to the tuner on 87 octane? Sorry didn't mean to hijack the thread.

 

Whoops, just got back.

99ls1z
I am afraid I didn't get the part number. Had it in my hand, looked straight through it, but I had a shop put it on. 297.00 for Catback, with the 18 and big chrome tip.
When the 18 was too loud, I asked for the next Magnaflow down, (or longer) and that was the 24. They swapped it free of charge.

If I can remember to I will call the place tomorrow and post. It may not be a 'retail' part. I did ask them what they would get for stock pipes, but adding the 18 a couple months ago, and they said 'between 100-150. So that's why I put that price range in.

You might call around local muffler shops, (not big chains who make the money on 'extra selling') and see what they get. I have used several local shops, and always got better work than I could have done myself.
Chris

 

pit, I have run the 87 octane with the Superchips about 3500 miles total, out of the last 5000 detuning it and then returning it to tune after a tank or so. About 500 miles of that I had it on the 91 octaine tune.

There is more power with the 87, not much more. You only notice it above about 3000 or so RPM. Better, not much better.
The advantage is the shift points, and firmness. Without the tuner, the truck feels 'mushy'. Just not quite right. With the tuner at 87 it feels firm, solid. Don't know if that helps, but that's the best way I can put it.

With the AEM, 91 octane tune, and Catback, it pushes you back a bit. If I hadn't put slightly oversize tires on it, it would spin on harsh pavment. On smoother pavement, it spins on launch. Most of the gain is above 3500, where it kicks tail.

This is in hot dry air, at 3000+ feet of altitude. Down around sea level, with moist cooler air, it spins out nicely on harsh pavement.
Chris

 

I agree, it does feel mushy...I'm going to be getting a tuner, even if I don't use the 91 octane setting much, better shift points and rev. limiter removed will make it worth it. Thanks!

 

You say your truck feels mushy without the tuner. When pressing the throttle it doesn't feel firm and it feels like you have to press it in a lot before you acting start gaining speed. It is not really like a delay but it feels like you have to keep pushing it in until you feel a little resistance and then you start moving good. Is this what you are referring to? Does the tuner correct this?

 

I was referring more to the throttle lag that seems inherent in these trucks and the slow/sliding shifting of the tranny. My understanding is that the tuner will take out the lag and improve the shift points, this would greatly increase the overall driveability even when using the 87 octane setting.

 

A 5.4 Lariat

 

What is your point?

 

Not really, the truck feels 'normal' without the tuner. I drove a dozen or three trucks prior to buying my STX, Chevy, Ford, Dodge, etc.

Stock the STX felt just like any other full size pickup. None of the 'throttle lag' that some of the 5.4 guys have stock.
With the tuner on 87 octane it makes it feel like it has an old style shift kit.
The sound, following it in another car, sounds performance, not truck.
Another way to say it is that with the tuner it has a 'snappy' shift.

If you drove one with tuner, you would know it.
If you hear one of these trucks go by, and the shifts are 'right now' it's a tuner.

It's like using a faster computer. You get used to it right away, but if you go back to the slow one, something seems wrong, even though it was working fine before you used the faster one..

Hope this gets it across.
Chris