ATTN: Flowmaster Dual 40 Series Owners

[off-road97Xplor]

Its very hard to explain what I'm trying to say so I'll draw a diagram in photchop and post it here.

 

[off-road97Xplor]

Now my questions is , will the Y-pipe in the second photo cause enough air restiction to result in performance loss? remember its going from duel 2 inch to Y-pipe 3 inch.

Diagrams:

 

[huskyfan23]

Why not one single size?

 

[off-road97Xplor]

I can't the mufflers 3inch inlet 2.5 inch outlet. So I have to upsize to 3inch in and downsize to 2.25 out. Is this correct?
Looking at the picture do you think the Y-Pipe before the muffler will cause any problems?
Would shops even make it?

 

[huskyfan23]

A shop would do it. I don't see any problems besides the 3" inlet. Why'd you buy a muffler with a 3" inlet?

 

[off-road97Xplor]

For a couple of reasons, I wanted a Original Flowmaster 40 series muffler with duel out, the only one that came with duel out was a 3 inch inlet. But, besides all that the number one reason was I got it for 40 bucks new.
Husky, I see you said that there will be problems with the 3" inlet? If they can downsize pipes what is wrong with upsizing? Maybe a different reason?
Thanx for all the help husky.

 

[Afboy143]

The only reason I would think that 3" would have is lack of back pressure. Remember, SOHC engines need backpressure to produce power. With dual exhaust you will notice some lost in torque but a increase in top end (what I found out when I got dual 50 series on my old truck.)

How much do custom Y pipes usually cost to be made at a shop? If I need two...Would it be easier to just buy a muffler made for dual in/dual out?

 

[icepounder]

Not to burst anyone's bubble but I just had a "true" dual exhaust installed on my X sport. It sounded good and seemed to perform good. I had it dyno'd stock and after the exhaust modification ... I lost HP and TQ and that's with 2 1/4" pipes.
I went back to the shop who recommended this and they are now working on a 2into2 or a 2into1.

 

[huskyfan23]

But aren't dyno runs +-4 hp/tq?

 

[icepounder]

Yes they are ... but after the time and money you would expect to see an increase not a loss. I was looking for performance gains not really a "sound". There were 3 runs stock (just intake mod) and 3 runs after the exhaust. The "best" run is used from each and that is using the same dyno and tester, 6500 rpm limit and sae scale.

 

[huskyfan23]

And I've been saying dual mufflers have a loss of power, but I'm sure it sounds badass.

 

[off-road97Xplor]

First off, never buy exhaust expecting horsepower increase, just buy it for sound. Thats what I did. A chip/intake/gears is what you want for performance.
Husky-You never said what the problem with my 3inch inlet was...

 

[huskyfan23]

You get performance with the proper sized tubing so do expect HP increase.

I doubt you'll have any problems. It's just weird.

 

[off-road97Xplor]

Do you think its not a true flowmaster? I got it from ebay. By the way, now that you mention it I'm not sure why it has a 3" inlet, it is wierd. I'll do some research.

 

[off-road97Xplor]

Nope, Checked everything, its a real flowmaster. It has no flowmaster logo stamped on it and he came in a brand new flowmaster box with the flowie papers inside. Checked the website and 3" Single In/ 2.5" duel out is an option.
No matter, im glad I got it for 40 bucks.

 

[huskyfan23]

I don't see anything weird about the 3" inlet, just you buying it for a vehicle with a 2.25" (?) outlet.

 

[off-road97Xplor]

I'm not keeping the stock tailpipe.
And I think for $40 its a great price to downsize it a .25 inch?

 

[Afboy143]

Yes they are ... but after the time and money you would expect to see an increase not a loss. I was looking for performance gains not really a "sound". There were 3 runs stock (just intake mod) and 3 runs after the exhaust. The "best" run is used from each and that is using the same dyno and tester, 6500 rpm limit and sae scale.

So what muffler/set up did you end up going into?

DId you have to dump your spare?

Which mufflers did you get? What inlets/outlets?

 

[icepounder]

So what muffler/set up did you end up going into?

DId you have to dump your spare?

Which mufflers did you get? What inlets/outlets?

The shop is working on getting me a custom FlowMaster made for me. To get some back pressure and still maintain a free flow affect we decided to go with a 2 in/ 2 out ( 2 1/4"). The problem is I had everything done in SS and FM only offers this particular muffler in aluminized. My guy is working on getting that muffler made of SS.

No I didn't dump the spare. I had the pipes routed out the right rear. This used less pipe, it has a nice look and hopefully better performance.

 

[Afboy143]

how much is this custom muffler, I really want a super 40 series with dual in/ dual out