Dyno Day

[XfireZ51]

Originally Posted by Bob Eyres

I have the Dr. Gas unit with 3" B&B's. It's the cheapest, and they have done quite a bit of development work on it, (with Mustangs).
Painted mild steel, not the prettiest, but works good. I clocked 117mph. in the qtr. with a stock motor, Coplon duct, Watsons, Dr. Gas X pipe and 3" dumps, no mufflers.

One "problem". It is loud enough to WAKE THE DEAD !!

Bob,

Which Dr.Gas X did you use? The X-over Junction or the X Scream tandem?

[Bob Eyres]

Originally Posted by XfireZ51

Bob,

Which Dr.Gas X did you use? The X-over Junction or the X Scream tandem?

This was a few years ago and they only offered one model. It looks like the X Scream Tandem pictured. I told them the exact length of the resonator that I was replacing, pipe size (3"), and the distance between the pipes. They fabbed one to match those dimensions. It fit nicely.

[XfireZ51]

I visited Al's Brakes Plus shop on Thursday. We took some measurements to replace the Mflow resonator. Looking at the alternatives, Al spent my money and I ordered a SW X pipe. Should be here this week.

[Pete]

Originally Posted by XfireZ51

I visited Al's Brakes Plus shop on Thursday. We took some measurements to replace the Mflow resonator. Looking at the alternatives, Al spent my money and I ordered a SW X pipe. Should be here this week.

Now that's using the old noggin,even though it had to be beat into you.

Your halfway there,now have Al order 2 mufflers for you,don't half a$$ it,let her breath.
It's like having a marathon runner breath thru a coffee stir.

Pete

[XfireZ51]

Pete,

I know I'm a stubborn WOP, but Paul is making 432 at the rear using the MFLOW muffs. For the purposes of getting the dyno run done, I'm leaving them on. I'll see if the drone is something I can tune/tolerate. If not I'll go w the Dynomax muff/flapper combo. Let's see what happens with the airbridge duct and resonator removal first.

[Pete]

Then you'll be happy with 432
Yeah your right your an old stuburn WOP

Pete(

[XfireZ51]

Originally Posted by Pete

Then you'll be happy with 432
Yeah your right your an old stuburn WOP

Pete(

Well at least not as old as Frank.

[jrtoffroad]

Originally Posted by Pete

Now that's using the old noggin,even though it had to be beat into you.

Your halfway there,now have Al order 2 mufflers for you,don't half a$$ it,let her breath.
It's like having a marathon runner breath thru a coffee stir.

Pete

Pete,

You really think the magnaflow mufflers would be a restriction? Have you seen them in person? They are nothing more than short 3" smooth perforated tubes. No baffles and no reduction in diameter.

I'm running a 3" system with a magnaflow x & mufs. It's loud and has some resonance with the top on, but sounds awesome with the top off.

[LGAFF]

Says on the SW website its ribbed for pleasure!

[XfireZ51]

All,

I just got off the phone with SW. The piece I got is their "resonated Xpipe". I was told by Paul at SW they don't build them any other way but they would for an extra $100. Needless to say, I'm confused. Paul W. I believe has a pic of his SW Xpipe and it was clear thru. The "baffling" is there to hold down the resonance. I agree w Lee that they are there to break up any standing waves which would actually impede flow. Maybe our resident Fluid Dynamics guy PW would care to chime in. The spiralling is similar to a rifle barrel leading me to believe it straightens out the gas flow. The twisting probably helps to "compact" the stream.
Discuss amongst yourselves.

JRT,

I agree. Don't see the impedence on the MFlow muffs. At the least, its negligible.