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5th & 6th VFR 800 Header build

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1 hour ago, Stray said:

Unfortunately that dyno didn’t provide torque values. 


We could calculate that. If someone was prepared to enter the power figures (read from the dyno graph) into a spreadsheet that could then be used to calculate and show the torque curve.


Further, if other data from other dyno runs with different exhausts was also entered, we could build up a set of torque/power stats that would provide the perfect comparison chart. The only issue with that would be differing parameters like actual bike and dyno used and atmospheric conditions etc. However, it WOULD be better than nothing.

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To address what you think about what I make of the lextek:
The primaries make a big difference in the midrange to where the cross of HP/Torque  happens.  

You can SEE the effect of enlarged primaries in Delkevic's own dyno results.  a pretty decent midrange bump,  and then the awful merges of it's POS 4-1 hodge podge cause a net loss of 5 hp or so on the topend.

They used to have the dynosheets up,  and they've since taken them down.  lol.  If you do a search around here you'll find them.  I might have one,  but I have to go to work.  to be continued.

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Case in point.  This is the '14 VFR with a Delk header.  Stock muffler.  picks up great in the midrange,  and then the complete shit merges and collector design causes it to LOSE high rpm horsepower to even the stock header and it's T junction merges,  if that tells you anything.

I'd have no issues recommending a delk header except:  it causes the VFR to completely fall on it's face after 9 grand.  

it's why I roll my eyes at delk headers,  it's why I'm actually very very angry about the BW/Ali/Lextek headers.  they're so close to nailing every aspect that it would've been likely cheaper,  to run the 36-38mm ID primary the whole way.  and make more power.  but they didn't.  It comes out of the header with the same squashed down ID as the stock '14 VFR,  which you see here get LEFT in the midrange by even 98 spec primaries.  Because that's what delk is running here,  32mm ID vs 30-29mm for the vtec era.  

They left (lots of) horsepower on the table.  for what,  so you could use the stock exhaust gaskets?  So they could save 10-20 dollars a header instead of doing a decent set of merges and slip joints?

lmfao  goddamn these companies.  

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