Member Contributer vfrcapn Posted August 2, 2014 Member Contributer Share Posted August 2, 2014 Instead of trying to dictate a price, why not just say that we will have about 20 (or 30) orders, and see what he comes back with. I don't think I would use the TBR price since they 'should' have all the tooling still, and we are requesting additional features and specific dimensions. Yes, just give him the specs and expected quantity and see what he replies with. THEN start negotiating...There are plenty of custom pipe shops in this country capable of this project. If you really want to drive prices down, get a list of 4-5 and send specs out to all of them, ask for their lowest bid. Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 2, 2014 Author Member Contributer Share Posted August 2, 2014 Guys... Post #252... Rod asked what price we were looking to pay... asked and answered... its not a big deal Quality is more important to me than the cheapest price... besides, there is nothing wrong with managing expectations Link to comment Share on other sites More sharing options...
Voided76 Posted August 2, 2014 Share Posted August 2, 2014 rush: idunno. twobros left a bit of a sour taste in my mouth with the whole 100 orders or gtfo deal. especially when it fits the new vfr, AND they should've had the tooling still. Link to comment Share on other sites More sharing options...
Grayv3 Posted August 2, 2014 Share Posted August 2, 2014 2002 stock catted header Good god that thing is ugly!! Link to comment Share on other sites More sharing options...
Spiff Posted August 2, 2014 Share Posted August 2, 2014 Guys... Post #252... Rod asked what price we were looking to pay...asked and answered... its not a big deal Quality is more important to me than the cheapest price... besides, there is nothing wrong with managing expectations I agree here. It does not have to be a two brothers, but something geared more towards the performance side versus the delkevics or the motads. Link to comment Share on other sites More sharing options...
Member Contributer Duc2V4 Posted August 2, 2014 Member Contributer Share Posted August 2, 2014 FYI. I sent Rod the photos and an offer to drop off the '98 headers I have... Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 2, 2014 Author Member Contributer Share Posted August 2, 2014 FYI. I sent Rod the photos and an offer to drop off the '98 headers I have... Hopefully, he is not too busy and he can work up a plan and an estimate... Link to comment Share on other sites More sharing options...
Voided76 Posted August 3, 2014 Share Posted August 3, 2014 a 98 doesn't have the o2 sensor bungs or the center stop.... =\ lol Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 3, 2014 Author Member Contributer Share Posted August 3, 2014 a 98 doesn't have the o2 sensor bungs or the center stop.... =\ lol Yes, we are aware of that... the '98 headers give relative dimensions for pipe material lengths, layout, and mounting locations for pricing & planning.... the O2 & center stand locations can be derived from the pictures We don't want the pipes laid out like the catted bikes with the front pipes crossing over... Link to comment Share on other sites More sharing options...
Voided76 Posted August 4, 2014 Share Posted August 4, 2014 well... yeah. I suppose not. with the big ass primaries, it could cause space issues. everyone would need to lose evap in that case, heh. Link to comment Share on other sites More sharing options...
Member Contributer Duc2V4 Posted August 4, 2014 Member Contributer Share Posted August 4, 2014 So i took some mufti-angle pics of the 98 headers yesterday and sent them to Rod this morning (well a link to the photobucket album). Waiting to hear back from him... Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 4, 2014 Author Member Contributer Share Posted August 4, 2014 well... yeah. I suppose not. with the big ass primaries, it could cause space issues... The cylinder primary merge connections layout look different to me too... My Y2K catted exhaust has the front primary crossover resulting in cyl #1+ #4 merge and #3 + #2 merge. My '99 headers have the same merge layout as the TBR headers... cyl #1 + #2 merge and #3 + #4 merge, that's the performance merge layout we want. Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted August 4, 2014 Member Contributer Share Posted August 4, 2014 " cyl #1 + #2 merge and #3 + #4 merge, that's the performance merge layout we want." This one ^^^^^. Right ? Link to comment Share on other sites More sharing options...
Member Contributer Duc2V4 Posted August 4, 2014 Member Contributer Share Posted August 4, 2014 In addition to the ones posted earlier, these are a few shots I sent to Rod today... Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 4, 2014 Author Member Contributer Share Posted August 4, 2014 " cyl #1 + #2 merge and #3 + #4 merge, that's the performance merge layout we want." This one ^^^^^. Right ? Yes... that is the layout of the TBR headers and the '98-'99 5th gens... For comparison... Y2k top... '99 5th gen ceramic coated bottom... Link to comment Share on other sites More sharing options...
Voided76 Posted August 4, 2014 Share Posted August 4, 2014 But... with the really outlandish firing order of the VFR, why wouldn't you want to join 1 and 3, 2 and 4? the exhaust pulse has the best chance of helping evacuate the other head's cyl. that way, does it not? you don't really -lose- or -gain- power going to the REALLY FREAKIN SMALL y2k + header, I am guessing, for this reason? Link to comment Share on other sites More sharing options...
Voided76 Posted August 4, 2014 Share Posted August 4, 2014 No. 1 fires at 0ºNo. 2 fires at 0º + 180º = 180ºNo. 3 fires at 180º + 270º = 450ºNo. 4 fires at 450º + 180º = 630ºNo. 1 fires again at 630º + 90º = 720º .... yanno? Link to comment Share on other sites More sharing options...
Member Contributer dgordon Posted August 4, 2014 Member Contributer Share Posted August 4, 2014 Please add my name to the "on the fence" list. This sounds excellent. Looking forward to the development and my thanks to those who got this initiative underway. Cheers. Dave Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 4, 2014 Author Member Contributer Share Posted August 4, 2014 But... with the really outlandish firing order of the VFR, why wouldn't you want to join 1 and 3, 2 and 4? the exhaust pulse has the best chance of helping evacuate the other head's cyl. that way, does it not? you don't really -lose- or -gain- power going to the REALLY FREAKIN SMALL y2k + header, I am guessing, for this reason? 1+3 (rear cylinders) and 2+4 (front cylinders) merging works on the 360 degree cranks of the RC30 and RC45... our bikes have 180 degree cranks where the 1+2 and 3+4 merging (same side of engine) works best. You can rationalize and calculate and engineer and computer model all you like... but to paraphrase what Eric Buell said, with exhaust flow you get close with the numbers, then you put it on a dyno and experiment until you get it right. The catted exhaust layout is designed to speed up heating of the catalyst and reduce sound pulse amplitude... the narrower ID primaries increase exhaust gas velocity and heat up the catalyst faster to reduce emissions and the crossed over connection and uneven primary lengths smooth out the exhaust pulses to reduce overall sound volume. That is one of the beautiful things here... we don't have to design to regulations like Honda did... our race headers that Rod or whoever makes... ahem, "For Off Road Use Only"... don't have to meet these requirements... Link to comment Share on other sites More sharing options...
Voided76 Posted August 4, 2014 Share Posted August 4, 2014 :) Well to summarize, I'm a layman with a brain that learns pretty quick when it comes to concepts ect, and honestly I was spitballing seeing whether it was a good idea, or if there was a damn fine reason why the 98/2bros is the way it is. if there's a way to squeak a horsepower or two from the 2bros design, it'd be nice to find it, lol. but I think they were PROBABLY on the ball in 98. heh. Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 4, 2014 Author Member Contributer Share Posted August 4, 2014 No. 1 fires at 0º No. 2 fires at 0º + 180º = 180º No. 3 fires at 180º + 270º = 450º No. 4 fires at 450º + 180º = 630º No. 1 fires again at 630º + 90º = 720º .... yanno? I see you've been reading up on the subject... Perhaps, http://www.vfrdiscussion.com/forum/index.php/topic/72962-rvf800rr-build/page-11 Link to comment Share on other sites More sharing options...
Member Contributer Switchblade Posted August 5, 2014 Member Contributer Share Posted August 5, 2014 " cyl #1 + #2 merge and #3 + #4 merge, that's the performance merge layout we want." This one ^^^^^. Right ? Yes... that is the layout of the TBR headers and the '98-'99 5th gens... For comparison... Y2k top... '99 5th gen ceramic coated bottom... 10-4 You use the previous exhaust pulse to help speed up the incoming correct ? Link to comment Share on other sites More sharing options...
Member Contributer TomP Posted August 5, 2014 Member Contributer Share Posted August 5, 2014 I've been following this and debating about throwing my name on the list, esp. given the back and forth on pipe diameter, which cylinders help scavenge which, etc. So ... what if we all chip in so Duc2V4 can do a before and after dyno run prior to the group buy? Realizing, of course, that YMMV according to other mods, etc. That way we know that we're buying more than sound, fury and a bitching looking set of pipes. Or maybe not. But at least we'll know. Link to comment Share on other sites More sharing options...
Voided76 Posted August 5, 2014 Share Posted August 5, 2014 I'm onboard. I'd chip 10 now in a paypal gesture I wish duc2v4 had a rapidbike on his testbed machine, that way we could see a baseline, timing boost, header, then post tune + timing. that'd be the proof of the pudding. Link to comment Share on other sites More sharing options...
Member Contributer Rush2112 Posted August 5, 2014 Author Member Contributer Share Posted August 5, 2014 " cyl #1 + #2 merge and #3 + #4 merge, that's the performance merge layout we want." This one ^^^^^. Right ? Yes... that is the layout of the TBR headers and the '98-'99 5th gens... For comparison... Y2k top... '99 5th gen ceramic coated bottom... 10-4 You use the previous exhaust pulse to help speed up the incoming correct ? In a nutshell, yes... there is a lot going on in the exhaust system. First, you want the exhaust gases to get out with minimal interference or resistance (back pressure). Then there is exhaust scavenging which uses the properties of the exhaust system to create a pull through the exhaust valve right before it closes and the intake valve has just opened (valve overlap). When this is done right the exhaust scavenging evacuates the combustion chamber of the last exhaust gases and draws fresh air/fuel charge into the cylinder starting the intake stroke before the exhaust valve has closed. To get exhaust scavenging you have the physical action of hot expanding gases that erupt out of the exhaust valve as it opens; this creates a pressure wave that travels faster (around the speed of sound) than the hot exhaust gases physically can (picture a ripple from a rock thrown in a river traveling downstream faster than the water), the exhaust gases are pushed out by the piston on the up exhaust stroke; the pressure wave will interact and reflect inside the exhaust; with a properly tuned exhaust the 1st major reflected wave (usually at the first merge) travels back up the primary and bounces off the exhaust ports and the back of the closing exhaust valves, this reflected wave in effect sucks through the closing exhaust valve scavenging the combustion chamber as it bounces off and travels back down the primary for the second time... Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.