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Measurements of exhaust system needed - please help!

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prorider17

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So I have a Leo Vince Evo II GP style muffler with every intention of fitting it to my FZ1. I don't have a mid-pipe, but saw that arrow makes one. I'm ready to pull the trigger, but really want to make sure I have the right measurements before I buy.

If I keep the header stock, buy the mid-pipe, and fit the muffler.. I need to know the measurements for it to work properly.

The arrow mid-pipe specs are below:
(Inlet) 61 mm diameter
(Outlet) 60 mm diameter

I just pulled the trigger and bought a power commander. :)
 
Is the Leo Vince Evo II GP made for the FZ1 or another bike?

I have Arrow headers but did not need the midpipe as my Akra slip-on came with one.

One of our members, super googan, has a new set of Arrow headers with the midpipe, I would PM him for the measurements.
 
Keep in mind that a well designed full exhaust system will give you a significant boost in midrange when compared to a slip on on the stock headers. If you are going to the effort now to fit the exhaust you might want to consider the Arrow headers as well. . . . . .
 
Don't know where your information comes from about full vs. slip-on. Unless I am missing something, all the dyno charts - Dale, Ivan, etc., show just the opposite - mid-range is lost with the full header system.
 
ElTigre1 said:
Don't know where your information comes from about full vs. slip-on. Unless I am missing something, all the dyno charts - Dale, Ivan, etc., show just the opposite - mid-range is lost with the full header system.
Click to expand...

I think you need to look at those charts again.

My own experience is that I have a huge gain in the midrange of around 10 -17 HP.

I do have a few extra mods but even stock the midrange is vastly improved.
There are a couple of minimal losses in the bottom end on a stock bike but the huge midrange improvements more than outweigh them.



Here is my chart with Akra slip-on and Arrow headers, note the very hefty improvement from 7-10K rpm:

FZ1_RPM.jpg


This is a stock FZ1 compared to Arrow slip-on and Arrow headers, it shows a slight loss around 4-5K rpm but then some big improvements in the midrange:

ArrowHeaders-1.jpg


This Yoshimura chart shows very slight losses down low but very nice midrange improvements also:

3514_3_.jpg
 
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The Yoshi slip on also yields gains in the mid range....not sure the 1 to 2 hp will make much differance in the real world.
 
For the Yosh full system, its about 8hp gain (over identical mods except with a slip on instead of full system) right around 6.5K. That's actually a lot of extra meat in mid range. Go to this post:
Full Yosh system tested-dyno charts - FZ1OA Message Board
Also keep in mind that the mapping wasn't optimized quite yet in those charts.

I have seen a number of other charts from forum members showing similar results from the "full package". Having about 25hp more than stock at 7k (about 100 fully modded vs about 75stock) is definitely noticeable! The full exhaust system is an integral part of this package. . . .
 
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