Bill/Cory Exhaust Thoughts

[dplummer87]

I did a search but didnt find anything, hope this has not been asked.

Anyway, I figure the guys doing the custom tuning around here have been around a dyno or 2 in their days...So my question is, have you noticed if any exhaust is "better" than the other? Now i know there is a fine line you guys probably have to walk because if you go and say Flowmaster (JUST AN EXAMPLE) performs the best on an F150, and all the guys here ran out and threw those on their trucks and felt like they lost power, or didnt gain any or whatever (people will look for reasons to complain) but I would really like to know, if you were to put an exhaust on your truck, what would you put on it?

Assuming you drive a truck (hopefully an F150 :cheesy smile:)


If its stock What exhaust would you put on it?

If its not stock, What exhaust do you have on it?

If its not stock, what exhaust would you wish you had gone with?

The real reason i ask is i know everyone here wants the biggest bang for their buck and are entrusting you with our money, and our trucks, so what exhaust would you recommend to work with your tunes...

Just curious :2thumbs:

[Caforddude]

I run a Banks Monster exhaust on my truck and like it a lot.

[Northern Supercrew]

Running stock still..maybe this sounds weird, but my exhaust sounds throatier with the custom tunes....it sounds like an aftermarket is on there...I don't see a reason to change it out yet.

[88Racing]

One thing if you are going after market exhaust shopping, is take into account of where you live and what you do with the truck.

1. Spend the extra $ go stainless. That's what the truck has on it anyways.

2. Posted this earlier in another thread if you remove cats, install long tube headers, true duals or do anything with the "y" pipe(any combination of these) you may need to have Bill adjust your customs.

3. Types or styles or mfgs the sky is the limit!

4. I have Gibson si-do sweptside behind wheel same side outlets.

5. I love the way Gibson sounds. I have always had one of their systems in any truck I have owned. The cars have had their mufflers be cherry bombs or thrush turbos or purple hornies.

6. Made the mistake on my 06 and had straight out the back under the bumper exits. Didn't sound to great in the cab when echoing off the flat front of the trailor. The right side seat noise also increased on that trip. Sold that setup to my budy.

Whatever you think about to install it's out there to buy.

Lars

[Jackpine]

I think Lars has given you some excellent advice here, dplummer. I wouldn't worry at all about people recommending a specific brand - it's what we did when we told everyone how much we like the Gryphon!

I think all you can do is get user feedback on what they've tried. It's all pretty subjective, in my opinion. I know, for instance, there is a bed cover I would recommend (A.R.E. - what I've had on two trucks now) and a brand I would not recommend that I had once - but I won't say the name publicly.

- Jack

[dplummer87]

I already know what exhaust im more than likely going to end up with...Im just wondering if the gang at PHP know of any exhaust that seem to put perform more than the others. Im talking strictly cat back...

[88Racing]

My thoughts on exhaust are also this:

If I knew now what I should have known then. I would have gone with the complete gutting and replaced everything from front to back. Kind of hard to justify a third system isn't it?

Lars:cheesy smile:

[dplummer87]

See, thats what i was thinking, i mean, IMO, by the time it gets to the muffler, the muffler is probably just being used as a "silencer" i mean, its already gone through the restricted headers and the restricted cats right?

So unless i put some headers and highflow cats, the muffler is probably just sound....? Logical thinking or no? Please correct me if its not. Im here to learn :thumbs up yellow:

[DOD 4.6]

I already know what exhaust im more than likely going to end up with...Im just wondering if the gang at PHP know of any exhaust that seem to put perform more than the others. Im talking strictly cat back...

if strictly cat back... i highly recommend the ROUSH off road system. Once i installed it, the truck idled perfectly and i honestly felt more mid range power. It's made of very high quality materials, simple install, looks great, and best of all - it's probably the best sounding cat back on an f150. hardly any freeway drone. check it out http://www.youtube.com/watch?v=80qxOFH6gds

[88Racing]

See, thats what i was thinking, i mean, IMO, by the time it gets to the muffler, the muffler is probably just being used as a "silencer" i mean, its already gone through the restricted headers and the restricted cats right?

So unless i put some headers and highflow cats, the muffler is probably just sound....? Logical thinking or no? Please correct me if its not. Im here to learn :thumbs up yellow:

Any cat back on the market sounds good with the exception of a few. Going motor back be prepared to sink some $$$$. Stay away from galvanized tubing and no name cheap stuff. There is a few catalog ones also to look out for. I will not mention any mfg names that are ? Because maybe someone else loves their system they put in.

My best advice is put a cat back on and try the gryphon with its customs. Maybe you won't feel the need to do more.

Lars

[Jackpine]

See, thats what i was thinking, i mean, IMO, by the time it gets to the muffler, the muffler is probably just being used as a "silencer" i mean, its already gone through the restricted headers and the restricted cats right?

So unless i put some headers and highflow cats, the muffler is probably just sound....? Logical thinking or no? Please correct me if its not. Im here to learn :thumbs up yellow:

Isn't a muffler simply for sound suppression? That's what I always learned. And the CAT is there to transform unburned hydrocarbons into something that's good for you like water vapor or carbon dioxide (as opposed to carbon monoxide).

But, the simple fact is, both these devices cause back pressure that prevents complete scavenging of the cylinders during the exhaust cycle. The introduction of Exhaust Gas Recirculation (EGR) sort of does the same thing, in the name of reducing Nitrous Oxide emissions I believe. So, for one reason or another, we're not going to get totally clear cylinders for the next intake cycle.

However, it IS possible, through a carefully tuned exhaust, to reduce the backpressure somewhat, which WILL increase the power available. You can even do it while staying within noise and emissions pollution limits. But, it takes a skillful exhaust specialist to make all this happen. I doubt it's any kind of simple "bolt-on" mod.

I think Lars and Cody posted a pretty good discussion of this a while back, but I'm too lazy to look for it.

What I took away from that discussion was that the results did not justify the expense, unless you're an absolute "purist" who doesn't mind throwing dollars in search of perfection!

One more thing that not everyone knows: You can't simply chop off the exhaust manifold and get a perfectly scavenging engine! This system is synergistic and needs to be TUNED to the engine to make things work properly!

- Jack

[88Racing]

Okay I know we are kinda blue oval fans here but I doug up a test we did in the mid 90's with two bowtie trucks.

1st subject was a 95 with a 5.7(350) obd1 system tbifi.
Cut out and removed muffler replaced with straight pipe. No loss in power gained .35 mpg. Definatly improved mid range and made towing boat seam easier.

2nd subject was a 96 5.7(350) with obd2 system tbifi.
Same thing was performed and the results to our suprise were this.
Lost 2.45 mpg. Passing became a chore even became more gutless
when pulling. Cooling system ran hotter. Also got numerous o2 cel lights. Put a aftermarket turbo muffler back on and everything was normal.

We figured out that obd2 systems were really sensetive to almost no backpressure situations and maybe that a higher rate of flow wasn't necessarily good for them.

Even some of the motors I built and put into cars, I found that straight exhaust wasn't the best for the motor. I got more power with backpressure and a x pipe.

So look at what you do and make sure it's the best and well tested product for your truck.

Lars

[Jackpine]

Good post, Lars!

I think you're right about the OBDII systems. I'm sure the PCMs are calibrated to "expect" the backpressure of a muffler and to work with it. When that backpressure is missing, I bet they try to compensate by reducing the outflow (which probably cuts the inflow of gas and air - so, less power).

- Jack

[Dixie Design]

I've talked quite a bit about my exhaust on these forums, there's a couple clips in my sig. I did a few things in steps rather than just going from stock to my current setup and would be happy to chat about it all again.

Here's the original post, and again check the clips in my sig they are the newest :)

http://dygytalworld.ehost-services139.com/forums/showthread.php?t=209&page=1

[DarrenWS6]

For a cat-back swap only, I also would suggest the Roush Off-Road. I still wish I had gone with it. The best performing exhaust is a 3" single for these trucks, with a 3" single tailpipe or dual 2.5" tailpipes.

One of the absolute best set=ups would the the Dynatech LT setup with Magnaflow hi-flow cats and Y pipe ( avail. as kit for $1400 from Troyer ) to a 3" single exhaust with a straight through muffler.

I noticed a little loss when I had my 2.5" true duals done. I had to have the sound though. True duals is not a good performance exhaust unless theres a cam and supercharger to back them up, otherwise stick with 2.25" for better scavenging. I couldn't bark the tires from a WOT punch after I got my exhaust, was able to again when I removed my rear converters, and i'm able to leave a couple black dashes with the Gryphon lol.

In general terms, my suggestion would be run 3" from the Y to a straight through muffler of some type ( Magnaflow, Roush kits, Bassani, Borla.. )