Placement of Flowmasters or H-pipe???

[Hafrod]

I have dual exhaust with 2 chamber Flowmasters. When I first got the car running I just had the mufflers hung in front of the rear end. I had no tailpipes. With my camshaft, it sounded evil. I had tailpipes put on to keep the inside of the car from smelling like exhaust. This changed the sound completely. To me it sounds like my ex neighbors farm truck with glasspacs. I'm going to get a completely new exhaust system built cause I bought some shorty style headers. Would placing the Flowmasters at the rear of the car (behind the bumper) change the exhaust tone or would an H-pipe cure the cackling? I don't have a money tree in my backyard to buy two different mufflers and this is the reason for this post. I'm trying to get a car finished for the Lonestar show in may and I'm on a very small budget.

[carls 56]

might want to just have the h-pipe installed and see what the diff is like. maybe would save you some money.

[Hafrod]

Hows it gonna save me money?

[Hafrod]

I might also add that the exhaust job I had done is CRAP. He kinked the pipes where they go over the rear end, it rattles sometimes and has a section spliced in. It looks like an amateur job to me. This is the reason for a new system. He argued with me on the 55,6, and 7s having dual exhaust from the factory. I was pretty sure that was part of the Power Pack option wasn't it? He said they NEVER had factory duals. I'll spend more $ for a better job from someone else.

[carls 56]

might not have to get a whole new exhaust system. ............... forget that, your going to get a new one anyway.

[Rick_L]

I think his point might be it's a lot simpler and easier than moving the mufflers behind the axle. They aren't going to fit too well there anyway.

The H pipe (or an X pipe) is going to change the pitch of your exhaust note. It will be higher pitch. With no H or X, you get four pulses per rev from each pipe with a V8. With the H or X, you get 8 pulses, doubling the pitch.

Another thing you can consider is a "resonator" at the end of the tailpipe. Essentially a small muffler. Maybe a tiny glasspack will do it.

And you're right, the power pack and higher options had dual exhaust from the factory. How they did it is in the assembly manual.

Flowmaster makes a pair of mandrel bent 2-1/2" tailpipes for 55-57s that fit and work well, and they are not expensive either.

[Hafrod]

That makes sense Rick on the four pulse to eight. I have a friend who has a 90s chevy truck. He has a single exhaust but has a Flowmaster and it sounds very nice. The H-pipe would make it sound like his truck.

[Hafrod]

I have the 55 Shop Manual but it has no pic of dual exhaust. I am curious on the rear section for duals because of the gas tank. He ran mine beside the gas tank and its touching on the left corner. This was the main area of his reason for the non factory duals argument. Anyone got a pic of the tailpipes placement with the frame and tank?

[oceangoer]

Halfrod,

I had straight pipes on my '56 about six years aog. The exhaust has two flow masters behind the cross member and staight out the back. Oh, and ceramic coated headers. A warmed over 350, but it sounded terriable and was Too Loud.

So my next sept was the crossover pipe or "H" pipe installed just behind the cross member but very close to the tranny tailshaft. The sound "quality" IMO was much better and a small performance gain, not that it matters.

But, it was still too loud and I cound not carry on a decient conversation or hear the radio.

So, as stated in one of your replies, I added two resonatiors just before the rear bumper - these were just a good quality glass pack. WHAT A DIFFERENCE.

THe sound was better and I could actually have a conversation in the car whle driving. But loader when accerating.

Then I installed a LS1 ans 6 speed 4 years ago. I have not yet installed the headers, still sitting on the shelf gathering dust. So the exhaust system is facorty Vette LS1 manifolds, cross over pipe, Flow Masters and the two glass packs.

The LS! is quieter during normal light driving, but you can tell is not a 327 or 359 as the soulnd is different. A different story when I "get om it",,l much louder. I like the sound.

I have used a cross over pipe in most of my street rods and cars. Always improved the sound quality.

I was concerned about the glass packs close to the fuel tank. I have checked the temperature on the fuel tank and other metal parts many times and it has not been an issue.

But, I am going to use the "bell" ends on my header pipes, from the headers to the mufflers,,, when I install the headers, soon I hope. This is so I can remove the headers if I need to replace the clutch or replace the Flow Masters.

I am thinking about removing the Flow Master and changing them out for a different brand. For once I would like you have flanges and not have to cut and weld !!

Good Luck,

Michael

[Moedog07]

I think the original dual exh. were 1 7/8 inch pipe. I just had 3 inch mandrel bent x-pipe ran on my car and space is limited. I can see why the small size tube would have been much easier to run. We could see where the other exh. pipes had ran over the years, it was very interesting.

There is not much room past the rear end for mufflers. Muffler placement would be much better ahead of the rear end. (IMO) Resonators or glass-packs, even the Honda fartcans could fit between the rear end and the bumper but it's tight with the spare tire drop down and gas tank.

I would recommend either a cross-over or a x-pipe.