My "modified" exhaust

I recently purchased a 2003 VFR800 with a "modified" factory exhaust. The endcaps to the exahaust look stock, so they apparently removed them and did some gutting of the exhaust. The sound is what I would describe as VERY LOUD!!! lol. I know people pay alot of money ($600-800) to achieve this.

Is their likely any other benefits? Some HP? I am not sure if I like or don't like it. I do like that people can hear me, so its a +1 for safety. I would actually consider if someone wanted to trade my nicely done modified stock exhaust for "pure" stock.

Would love to sync up with someone "local" (aka South Florida), to hear my bike and compare to their stock or aftermarket and give me some honest 411.

Brian

 

PS I am going to post some sound clips, perhaps this weekend, I am out of town until then

 

Gut exhaust cost about $30 and a day of work.........lol

 

No doubt, I didn't mean to imply that gutting the exhaust was expensive, I meant that people pay $600+ for an aftermarket system to achieve a similar result. I have seen many different types of factory gutting, and the most sophisticated maintains the factory look, without shaving off the tips. This looks 100% stock, and I am still trying to figure out if I like the sound or not.

 

Signal bring a case of IPA and you can have my stock new took of from the bike :wink:

 

Where in south florida? Im in sarasota and have 08 vfr stock exhaust

 

I am in Royal Palm Beach which is Palm Beach County

 

Get real exhaust, a PCIII, and enjoy more power. Gutted exhaust does nothing but rob power. Unless you've ported and flowed your heads and intake system to match.

 

Do you have any dyno #'s to back that up? otstir:

From what I have heard (here and on vfrd) - and it's all fairly anecdotal :gossip: , almost anything you do to just the 'cans on a 6th gen vfr has very little performance effect one way or the other, and that the greatest restriction in the exhaust system occurs in the lower part of the system - collector, cat, and o2 sensors, not in the cans.

Modifying the heads or the intake system would have little to do with a minor modification like a change in the 'cans. Porting, port matching and polishing is one of those things racers do when they are looking for every last bit of clean air flow and exhaust flow (to gain power - usually at the expense of torque - but not always), and would be of little benefit without a complete exhaust system change.

Cam changes, increased compression, more fuel and timing, better air flow and better scavenging are reliable ways to increase peak HP (again, usually at the expense of torque and drive-ability), but most of these somewhat extreme hot-rodding engine techniques just seem kind of silly for the VFR. :funky: The torocharger (if it was still available) makes the most sense as a power adder. :flex:

My unscientific butt dyno tells me my bike seems slightly more responsive with my fully gutted cans (only thing left to cause any restriction is the perforated metal prior to the main muffler assemblies).
I really could not tell for sure, so I did a little informal testing - I switched back and forth with the stock system, and tested with an accelerometer based dyno, and there was again, no discernible difference. Perhaps a real dyno would have finer resolution, but I'm just not seeing any significant difference in performance.

The exhaust note is just a little louder - but not as loud as the other VFR aftermarket systems - and way quieter than any HD with loud pipes.

Maybe with a PCV or a rapidbike and some dyno time I could pick up a few extra hp, but my main goal if I go with a tuner is to smooth out the lean part throttle :twitch: issue common to the stock 6th gen.

If anyone has some reliable, comparative dyno #s for the following: stock 6th gen, gutted exhaust 6th gen, aftermarket cans, full exhaust, and all of the above with tuning, that would be great.

I know Tink has done some dyno time, but I can't remember what the conclusions were. hwell:

op2:

 

Weight savings will also play a role.

Going from gutted to aftermarket may not yeild much as far as dyno, but the weight savings will effect the overall acceration/top end speeds. I plan on dropping about 25-30lbs going from an OEM tail/exhaust to a baffled open cat with fully fiberglass tail section and LED lighting. Will this improve dyno HP? probably not, but I will feel the lower center of balance and weight loss on the road.

-Drew

 

i have never heard that a gutted exhaust "robs" performance. i can't imagine how that would be true, as i would have thought to see this flag thrown many times before

 

So... something similar to a Buell. otstir:

 

HAHA.

Similar to several bikes- two of which being the Buells and the Ducati panagali

Buell had a lot of innocative ideas- the oil in the swingarm, gas in the frame, huge front rotors, and underbody exhaust were all good ideas he just had a crap powerplant to try and piece it all together. Obviously, it was better on paper than in practice.

-Drew

 

I have a 2007 with a Two Brothers, you can get a good idea of the sound on some of the youtube videos. I'm in Port Orange, too far for a quick sound check. At idle or highway speed my noise level is just above a stock exhaust, when on the throttle it has more depth,and distinct combustion pulses , a very indentifiable V4 growl. Not anywhere near gutted stock cans.

 

I have had it with this gutted stock exhaust. I am going to buy the Two Brothers Carbon Black setup. I watched many of the videos and it looks nice, sounds nice, and you can add the adapter things to quiet it if need be. Plus it will save some weight. I want to do this before I drop in a PC