Help fund the VFR header

Ok , here we go nothing to much to say other than.. wow, some what disappointing, sorta. So much so, even Mike was going WTH......All though as good as the throttle responce is, still didn't off set the loss, even tried it with out the Staintune, thinking here its a mid pipe tuning thing? but Oh brother it was worse. Head scratching..then he heard me say I had installed a Piper cross filter, he shook his head and said what? So I'm re installing the KN and adding new plugs, Next week I'm doing this again. in the mean time enjoy these couple of videos.

Chart
Red was last years tune with KN.
Blue is with the 2Bros + Piper
Green was base line from the start




Staintune pull

https://www.youtube.com/watch?v=O9Wn7xHnVGE

Open header

https://www.youtube.com/watch?v=r6-ndDG5BCA

 

So is he saying the Piper Cross actually hurt your performance? Any explanation?

 

I send my condolences. For now, it looks like that chart has poked a couple holes in things.

 

Mike didn't really come out and say it's the Piper, but was saying since it not so much a coming out thing, so it must be a getting in thing. He's seen a lot of systems, pretty sharp tac when it comes to this, and was quite surprised in the results. He fiddled with the fuel map a lot, at the best we saw a 112.5 hp pull on one run. but most where hovering @ 111.8 -112.05 The pull here with this chart was done making the comparisons. Viffer only made 110hp open header and the torque just fell off.

 

Boy, sorry for all the work; it was a major faff to install. But, I've suspected as much all along. If there was easy, cheap, horsepower to be had through exhaust headers, Honda would have done it. They likely optimized stock header diameters for torque/street riding given cam profiles, valve sizes, throttle body sizes, etc.

My guess is the K&N won't change anything.

Someone will pop up here momentarily and tell you where you and *Mike Velasco* went wrong. Me, I appreciate your trials and tribulations for the VFR team.

 

Yea, it's a learning curve, but there's always a trade off, unless one digs deep into an engine. I won't go and say Honda did their best here, just a get by with, with the bean counters calling the shots and all. So to a point your on Que. Even that said Mike was shaking his head it didn't make sense to see for the most part no gains. in fact it's like 4hp down in a good part of the range. We where talking later, that most systems on like CBRs where the dude comes in with a new system all puffed up claiming we'll see 10-15hp. in most cases it more like 5-6hp. Even with this here, it didn't make more hps until the top, was perplexing to say the least, we ain't done, but does answer some of the questions. If all else fails, I'll throw the stock header back on. But the Viffer does run pretty darn good , So??

 

Well your not a quitter, and of those gains in the mid range and top end, plus better throttle response I think it's a positive and your fabrication is not for not--- keep up the good work Jmon

 

Can't say I'm completely shocked, a lot more work goes into an exhaust system than you might think. Personally I would be interested in a set of headers which linked the pipes diagonally, almost running the cylinders as two separate v-twin systems.

Looks sexy tho :thumbsup:

 

I wrench on my own bike but I wouldn't even claim to be a shade tree mechanic. Disclaimer now stated, I think the loss of power might be something else, as in maybe if you dyno'ed the bike in the same configuration as it was in last year, the graphs would still be lower than compared to what you got before. And/or maybe you need to make some additional mods/changes to take advantage of the 2Bros. Either way, if the butt dyno feels good, and your mileage is ok, I think that's all that matters? Btw, the open header sounds Absolutely Awesome!!! Reminds me of my 87!

 

Well that's a bummer. Don't forget this Dyno was done in 62*F vs 52*F, so it could be conditions related. How do the two maps look? More or less fuel? Anyways yeah it's definitely worth trying the KN filter and the OEM header again, to see if the loss is just the 10* temperature increase or if the header and filter are a dud. Still disappointing nonetheless. Sorry man.

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Awe, thanks for the nudge, forgot that one, here's the fuel map comparison..

 

The temp difference was 10*, not 25*, but it also had 6% less humidity, so that's a wash. I doubt either of these two contributed to what is being indicated. I would be skeptical if new plugs and an air filter would correct the package. Personally, I would go back to the original exhaust and filter, the 2 Bros and Pipercross got trounced across the board and only managed to increase the overrun.

 

Can't argue that point, and more than likely after another pull, as I'd like to know just what is. from that I'll know more, like you I'm doubting it will pull to at least the same. if not, I'll swap it back around. Still, it does have excellent throttle response, Go figure. But losing 4hp through most of where I run, ain't in my book to have. We'll see, kinda fun doing this.

 

It looks like it was tuned significantly richer across the board. That could account for the power loss and increased throttle response.

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There were no gains, only losses; the blue trace is the 2 Bros system.

 

And there it is, just as predicted!

 

Yeah you're right. Looking at the notes:

52.49*F, 0.98 correction factor and 111.17hp corrected = 113.44 actual

Vs

62.53*F, 0.99 correction factor and 111.93hp corrected = 113.10 actual

So the temperature went up 10 degrees and the bike lost 0.34 actual hp at peak. It's weird that the fuel curves are totally different. I don't think humidity is as big of a factor as temperature, but disappointing, still.

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There are gains from 10,500 to redline, but it's not worth the loss everywhere under 10,500.

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My 01 headers are crossed up front, its the same for the 6 Gens, at least on my 09. Based on the version of 5 Gen RVFR has, the 2 Bros. matches his OEM headers. Have to wonder what Honda did between the early and later 5 Gens.

 

Would be great if it was due to something simple like old/worn spark plugs...