sfdownhill

MadScientist, your expertise goes right to the crux...at the welds inside the primaries of header #2 there are bits of weld material just barely protruding into the gas path around the internal circumference. I tried to reach in with the Dremel extension and hone down the intrusive weld material, but those bits are tough! They laughed at the high speed grinding tip. Yes, something in header #2 disrupted the combination of factors that make the TBR design so effective. boOZZIE, I'm not sure when/if we'll be able to get a mandrel bent production header onto the dyno - we'd certainly like to do so soon. Wade ordered materials and sent his design specs to his bender vendor, so we'll see how quickly completed production headers get shipped out. I'm going to ask him for a timeline when I see him Tuesday. I hope it's not long before we all get to see a dyno baseline and tuning of a production header. This may be something a customer from the list of persons who have placed deposits gets to first, soon after they receive their headers. At this time it appears the next known dyno baseline/tune on this project will be prototype #1 on VFRD member Hammerdrill's 6th gen, as he is purchasing those headers. Hammerdrill is having an exhaust shop open up the cans of his OEM 6th gen mufflers, gut them, install 1.5" perforated exhaust tubes and pack them. He's keeping the OEM muffler carcasses for their aesthestics. When the mufflers are done, he's going to get his 6th gen to Attack as soon as possible. Note: Prototype #2 is available for purchase at this time. Airisom, Mohawk's curiosity about a crossover header that matches the design of the 6th gen OEM headers but employs TBR tubing sizes and merges does get one pondering... Sadly, we are not equipped with time or resources [read: dinero] to pursue further prototypes and testing.

We finished up a second phase of R&D Thursday - dyno testing of the header - prototype #2 - in the photos below at Attack Performance. All this means is that one well researched attempt to improve on header #1 only proved #1 to be better. Production continues w header #1 the original TBR replica as scheduled. I am driving out to Wade’s shop Tuesday to go over proper alignment of the collector exit, taking along 98/99 headers, TBR headers, a center stand, and maybe the fitment bike. Here is header #2: Based on (1) exhaust theory of keeping gas velocity high through the port by maintaining a slightly smaller diameter in the first few inches of the primaries, (2) Wade’s success with this concept on his dwarf car and Razr headers (3) Black Widow and Lextek’s use of this concept, we had Wade build a second prototype with smaller 35mm od for the first 3.5 inches starting at the exhaust port. The results are clear - header #1 we tested on Saturday Jan 26 is definitely better. This chart shows header #2 down a couple hp and ft/lbs across the entire range, especially in midrange Note: Dynojet dynos/software correct temperature, humidity, and altitude to a standard density altitude. This means the software corrects to a standard the same way aviation performance calculations are made, ie “Can this aircraft generate enough power and lift to take off from this runway at this weight, altitude, temperature, and humidity?” Dynojet’s correction calcs are not perfect, and neither is my spelling, but they are better than nothing. Here is an uncorrected comparison of last Saturday’s run of header #1 against Thursday’s run of header #2:

Now that is enlightening reading. Thanks for sharing the knowledge-wealth, Mohawk. The Rob's Dyno article mentions RC Engineering's fuel injector selection table, which got me looking further into RC. Now I'm extra happy we used them for our injector service. Once again thanks are due to Duc2V4, this time for bringing RC Engineering Fuel Injection to our project.

MooseMoose and Mohawk - thanks for explaining further how the 2000-2001 5th gen ECU reads the O2 sensors. I did not have a clear understanding of it, or how the O2 Optimizers functioned. Always learning. It makes sense that the baseline runs were rich even with no fuel management system installed: the O2 Optimizers were still installed because the 98/99 headers have no bungs. Thus the ECU defaulted to its rich map. Zarquon, the interference issues when using a PCV on a 5th gen do seem to be limited to the 5.2 gens (2000-2001). MadScientist has a PCV rocking his 98. Here’s the bike ready for action on the dyno. We were all surprised the coolant temp stayed between 170-180F throughout all the sessions. Even Jozef was expecting to see high temps with the side mounted radiators during power runs.

You are spot on, Scottie: we are cooking up a recipe with results that can be duplicated by other VFR owners.

Yeah! A bit disappointing, but we could hear it howling on the other side of the concrete wall we were pitted against. We could hear him really putting it through its paces.

MadSci and boOZZIE - We ran out of daylight, time, and closed the Attack facility down on Saturday night, last car in the parking lot was us, packing up the pit and loading the bike, so I didn't get the files from Jozef then. He said he'd email them, and I'll be going back up there later this week, so I'll take some photos of the Attack bikes and get the fuel maps on a thumb drive if he hasn't emailed them by then. I did not ask him to save the original PC3 map, but hope he did - I'm as curious as you are about the difference in mapping. The original map was from a dyno tune back in 2006 done by the previous owner of the bike. At that time it had a California ECU, Staintune slipon, and OEM air filter which all combined to achieve 99rwhp on the dyno. In other words, the original map is probably going to be quite an apple compared to this recent orange. MooseMoose, I agree with your observations; the AFRs are just a touch on the rich side, which is a fairly safe place to be. I suspect that the AFRs on the baseline runs stayed rich for two reasons: [1] during the baseline runs, the bike was never run in steady state throttle long enough for the ECU to go into closed loop fueling, which is where it would start paying attention to the O2 sensors and leaning the mixture to optimize efficiency, and [2] the O2 sensor leads from the ECU are terminated with Dynojet O2 Optimizers, which tell the ECU everything is hunky dory with the AFR, so even if it tried to go into closed loop fueling, it wouldn't perceive an opportunity to lean the mixture. And you are right about the end result being better rideability - most of us spend 90% of our fun riding time in the midrange rpms, and that is where throttle response is all different with the TBR. I was a skeptic about headers until I rode RVFR's 5th gen. When we traded bikes for 20 or so miles of twisties, his 5th gen was set up exactly as mine was except for the headers: both bikes had PC3, stock engine, and Staintune high mount slipons. He had installed a TBR header and the package had been tuned by an extremely good dyno tech. My mind was forever warped.

The PC3 was installed before the session during which runfile 14 was produced. Before that session, Jozef went in and zeroed the PC3’s map so it made no changes to stock ECU settings or actions. Part of his protocol is to get a reading on changes a modification makes by itself, with no tuning whatsoever. To be certain there are no contrary actions lurking in the PC3, he creates the zero map himself by entering zero values across the entire table (there is a command to enter all zero values - he didn’t have to enter them one cell at a time).

FOR SALE - one Power Commander V, Dynojet part #16-005 for 1998-2009 Honda VFR800s. Like new, very little use. Produces dyno charts like this when installed on a 2001 5th gen VFR: The short story: Success. 3.62hp increase after simply bolting on the new header with zero tuning. 7.63hp increase after tuning the new header with Power Commander 3 installed. The long version including dyno charts: Yesterday's dyno sessions ended up being very productive. At $775, It also cost quite a bit more than expected [See invoice below]. This will result in a $30/per header increase in cost for orders placed from here on out - meaning headers not deposited at this time will cost $790 plus shipping. We will honor original pricing of $760 plus shipping for each header on all orders for which deposits have already been received. The day started early, meeting with Jozef [lead dynamometer technician] in Attack Performance's impressive lobby at their Huntington Beach CA headquarters. The lobby has several of Attack's MotoGP and championship winning motorcycles on display - badass hardware bristling with hardcore race tech. After going over our plan for the day with Jozef, Duc2V4 and I set up our pits, unloaded the bike, and handed it over to the wizard. Jozef took the bike 'behind the curtain', as Attack's shop is off limits to customers. Here's where the first evidence of skimpy photo documentation surfaces - although Jozef snapped a shot of the 5th gen on the dyno with prominent Attack logos in evidence, I neglected to collect even a text of the photo. Massive thanks to VFRD member Hammerdrill for filling in with the much needed photos seen later in this post. The 5th gen test bike started the day with 59877 miles, Power Commander V with zero map, a new K&N air filter, new Denso iridium plugs, PAIR system disabled/removed, ~1000 miles on Mobil 1 oil/filter, a Two Brother Racing slipon muffler, and OEM Honda 1998/1999 headers installed. The dyno chart at the top of the post is from the first set of dyno runs. After recording these, Jozef brought the bike back out to us - something was definitely wrong. To keep this account of the conversation brief, I'll just recount that Jozef said he'd never seen a bike run this wonkily with a PCV. The erratic readings were the result of electrical interference of unknown origin. Group deduction arrived at the possibility that the problem could be with the speed wire tapped into the Power Commander V, so we disconnected it and Jozef took the bike back into his cave. No dice, Jozef got the same misfiring and erratic results. Back in our sumptuous VIP pit area, troubleshooting arrived at disconnecting the PCV, so we did. After disconnecting the PCV, the bike ran well and these baseline runs were the result: Having acquired a successful baseline and simultaneously possessing a fuel management system that consistently sent the test bike into a tizzy, it was vital to best martial our remaining time. This meant I would drive back to Vista and pick up the PCIIIUSB which had been strategically left at home, 70 miles away from Attack Performance. Can't blame the PCIIIUSB, it would have loved to have been on the first trip to Huntington Beach. Not even the PCV can be blamed...I had singlehandedly done all the forgetting. While I was gone from Attack, Duc2V4 would change out the 98/99 headers for the prototype, Hammerdrill would take photos, and Jozef would continue building engines for Attack, then take a long lunch. Duc2V4 did a stellar job getting the 98/99 headers off and the prototype header installed. [All photos courtesy of VFRD member Hammerdrill - thanks dude!] Special tools were required to disconnect the rear primaries: Who left these rings under my pillow? And here's how he stuck 'em into the exhaust port sleeves: This is one of the 42mm crush gaskets after being crushed by the prototype header. Note the space between the gasket's id and the port. [This is the photo I forgot to take on fitment day]: Gaskets in place. Look ma, no grease! They stay in place on their own: Prototype headers connected to a midpipe Wade built to fit the TBR canister. Duc2V4 found a way to make a too-large T-bolt clamp fit onto the midpipe - note the spacer on the threads under the clamp's nut. Also note how frickin close the prototype came to the shock linkage. This would have been of concern if the bike wasn't on a rear stand when this photo was taken - the rear wheel was hanging at its maximum extension and still cleared the collector: The incredibly hard-working pit crew: After 'lunch', with PC3 and new prototype header installed [Connected to the same TBR canister used for the baseline] Jozef got down to business and completed an exhaustive [ouch again!] tune, resulting in the comparative graph below. The bottom trace Run File 10 is the baseline 107.5hp / 57.01ft/lbs The middle trace Run File 14 is the 'just slapped the headers on' with no tuning whatsoever 110.86hp / 57.82ft/lbs The top trace Run File 77 is the result of Jozef's careful tuning 114.74hp / 59.82ft/lbs After the dust had settled, Jozef placed a midrange reference line at 8000rpm: And the ugly:

pdf vs jpeg vs scanning utility [vs Predator?] issues. Any patience that can be contributed is appreciated.

What are the group thoughts on header slip joint integrity? I've heard they may leak, but Wade doesn't seem concerned about that possibility. They aren't the easiest things in the world to pull apart, but that may be partly because the two slip joints aren't parallel. Also, the fit of the midpipe into the TBR slipon canister is a little rattley. Would exhaust wrap tighten this up? Does anyone know of an exhaust sealing tape? All the high temp exhaust sealants I've found require 24 hours to cure. We'll be assembling the headers and running them within a couple hours, so no time for slip joint sealant to cure. Anybody have a working solution or a 'why dontcha try' suggestion?

Big shout out to moosemoose - thanks for loaning your carb synch suction tool gizmo so I can synch the starter valves! Don't know how the new exhaust sounds yet - the fitment bike is a fair ways from running. I'm certainly among the curious about the sound. Here are weights, based on bathroom scale technique, meaning I stepped on and off and reset the scale between readings until I got three identical readings, approximate to the tenth of a pound: TBR with no springs installed [sorry, should have had the springs on to match up the weights, but a guy can only stand stepping on and off a bathroom scale so many times, and I didn't catch the missing springs until I was putting the TBR to bed]: 8.4 lbs [Is that really only 3.8 kg?] Prototype with springs and O2 sensor bungs: 9.5 lbs 4.3 kg [again, only if my conversion math is correct] Items that came to light with the prototype: - the collector exit pipe is too close to the descending cylinder #1 primary. A factor here was the cylinder #1 primary should have stayed closer to the radius of the cylinder #3 primary as it swept down and forward toward the merge. This was partly because of modeling on the TBR, partly because of not having a fitment bike while building the jig. There will be more space between #1 primary and the collector exit on production headers. - the vertical descending portions of #1 and #3 primaries at the slip joints are not parallel, which makes installation and removal a bit of a grunt. This also was attributed to modeling on the TBR. Upon inspection, sure enough, the TBR #1 and #3 primaries are not parallel where they are vertical behind the heat shield. - how best to equip 6th gen owners with a center stand stop was not completely resolved. Possibilities are still being explored. Wade does not endorse welding on a bracket of the length that would be required to locate a stop in the OEM position [OEM stop bracket is fastened to the rear of the catalytic converter]. He is open to having midpipes sent to him to have a stop welded on, a la 5th gen [see photos]. He also can fabricate midpipes with stops welded on. - the 41mm crush washers [from Delkevic] closed down to 31.5mm id when the stud nuts were torqued - that's too small for our 32.5mm exhaust port. - the skinny round cross section copper 42mm crush washers worked great [also from Delkevic but not listed on their website or ebay store]. You have to work them by hand into the id of the exhaust sleeve on the head, then the prototype primary just pushes the gasket down to the base of the the sleeve at the port and flattens it there. After crushing, the id of the gasket is 0.8mm larger than the exhaust port - there is space [0.4-0.5mm or precisely four hairwidths] between the inside perimeter of the the gasket and the exhaust port all the way around. I'll post photos of a successfully crushed gasket at the exhaust port once the prototype is removed from the fitment bike.

Yep, the new headers fit well onto the 5th gen fitment bike. Just finished unloading from yesterday's field trip, and recognize some data is due. Details to follow soon.

Mohawk, I have this filed as CandyRedRC46's:

Thanks for input Seb and Mohawk I have 10 of the 42mm crush gaskets from UK pictured below. Uncrushed it measures 41.67od 33.61id. Its leading edge can be wedged into the exhaust sleeve on the head, but will probably be deformed by the header before bottoming out in the sleeve: This is what the same gasket looks like after being chucked up in a lathe in an attempt to shave the od for a better fit. So score=1 sacrificial lamb gasket, 9 gaskets remaining for testing: I have not been able to locate the perfect round section copper 42mm crush gasket described elsewhere, but have acquired 10 each of two more gaskets to be tested. The one on the left is billed as 41mm, but before crushing is 40.3od 31.7id, so id is too small. The one on the right is listed as 42mm, and before crushing measures 41.7od 36.3id and can be wheedled into the outside edge of the exhaust sleeve, so has potential [kinda skinny, though].

Thanks Greg. I've ordered stainless and mild steel bungs with 25mm height [What can't you find on Amazon?], like the contoured bung you are using. I don't know welding, whether bungs have to be stainless to weld to stainless, and I forgot to ask Wade this question when I spoke to him, so I ordered bungs in both materials to have both bases covered for the fitment test this Tuesday Jan 22. Wade didn't have any tall bungs on hand at his shop, and I try to keep things easy for him. I hear you thtanner - sifting through posts for updates is tedious. People who are planning upgrades/updates around their new exhaust might find value in the thread having a linear progression. There probably won't be much until Tuesday night, after the fitment session. Tuesday we'll be at Wade's shop [1] testing 3 different crush gaskets to see which works best with the new headers [2] swinging the new headers into place on a fitment 5th gen [praying the TBR they were modeled from were in good shape] [3] checking the new header's collector exit location and angle on the fitment bike with a selection of OEM and aftermarket slipons [4] checking center stand installation/fitment and exploring possible 6th gen CSS location [5] making a midpipe to fit between the new headers and a TBR slipon. The TBR slipon canister is probably going to be used on dyno day [Sat Jan 26] because Wade isn't sure if he'll have a full system ready in time for testing.

Jozef measured the Bosch wide band sensors he uses with the Attack dyno for tuning and came up with 27mm from the base/seat of the sensor’s threads to the sensing tip. This would be the same measurement as from the top of the bung to the sensor’s tip when installed. If anyone has a different measurement for the Bosch 4.9, please let me know.

I'm very grateful for all the sage advice and constructive suggestions offered here, especially in the last day or so. Mohawk, when you capitalized 'YES' in answer to me asking if I should cease and desist, it had me rolling around laughing - well said! Your reminder that today's O2 sensors do not require external heat from the exhaust, therefore are less sensitive to placement than past sensors was also highly valued. HighsideNZ, good input on air filter choice, preparation, and not modifying or changing anything on the motorcycle between the baseline and tuning except the headers.. GreginDenver, you chimed in with exactly the info I was seeking at just the right time - how cool that you work in and around injection systems and motorcycles. Wait until you see our donor/fitment bike...it's in serious need of the full GiD [Greg in Denver] treatment. After the dyno dust settles, the fitment bike will get the best version of your rebuild I can muster. Duc2V4 and I are in agreement with the fundamental objective everyone is voicing: exercise discipline in changing only the headers between the baseline run and the dyno tuning session because we are all seeking only accurate information on the changes the new header produces. Nothing else. Peripheral tweaking and tuning will only diminish the validity of our findings. Because the dyno tune needs to be performed, it makes sense to optimize the configuration of the test bike prior to arriving at Attack Performance, then change absolutely nada, zero, nothing in this configuration except the headers between the baseline and the tune. Thorough preparation will allow the best tune and be best for the bike in the long run. If the bike is prepared for the baseline run with new spark plugs, recently calibrated fuel injectors, a fresh valve adjustment, starter valves synched, new coolant and thermostat, a new air filter, new oil/filter, , fresh fuel, and PCV, then, after the tuning session, it will be a complete package dialed in for the second half of its life.

The 5th gen that will be used to dyno test the new header is currently equipped with a Pipercross air filter. The Pipercross was clean and still moist with oil when last checked 2378 miles ago. There was a thorough discussion of foam vs pleated filter mediums on an earlier header thread. RVFR relayed solid input from his dyno tuner, Mike Velasco, a legendary Honda V4 tuner [Mike tuned for Freddie Spencer, Fred Merkel, Bubba Shobert, etc]. RVFR, please chime in if I've gotten the information from Mr. Velasco wrong. I do recall that his recommendation was to get rid of the foam filter. The discussion begins in the link below, starting with the May 9 2017 post. MadScientist delivers an authoritative, experience-based treatise on the relationship of filter area, pore size [filtration], and pressure across the filter: https://www.vfrdiscussion.com/index.php?/forums/topic/85354-5th-6th-vfr-800-header-build/&page=4 Checking it out the link he posted back in 2017 reveals that once again, mello dude is one of the best guys on the VFR planet to listen to; the BMC appears to have nearly [exactly?] the same oiled multi-layered cotton filter medium area as the mysterious big mouth K&N. BMC claims 'several layers' while K&N claims four. And the BMC is readily available - no manufacturer scavenger hunt required: https://www.bmcairfilters.com/eng/standard-bike-filters/fm187-04-01/1440/art Here's the big mouth K&N HA-8098, next to the standard K&N HA-8098:

Thanks for the solid input everyone. Between the solid recommendations here, the guys at Attack, and Wade, we’ll get an accurate result. Separate note: it’s a good thing we had the injectors serviced - see printout below. Valve adjustment is taking place now. I’ve got a tech support ticket opened up w K&N to engage them in the search for the big mouth HA-8098. Even after putting photos of the two animals that both have K&N part number HA-8098 stamped into them, K&N is having a hard time getting their arms around the concept.

Agreed, ducnut. You don't pay a lawyer $300/hour then ignore their advice. I'm working to reconcile Wade's concern as the builder with Richard and Jozef's thoroughly vetted tuning procedure. To fly in the face of Wade's direct recommendation at this point would send a message to him that our community does not intend to send.

Sounds good Scottie. BTW, you have discerning taste in race bikes!

May I please tap into the collective knowledge base about O2 sensor bung placement? Jozef, the dyno tech/engine builder/tuner at Attack Performance, recommends an O2 sensor in each primary 7 inches from the port for optimum tuning. Jozef has Bosch 4.9 wideband sensors that he installs to facilitate his tuning. The O2 sensors will be removed and the bungs plugged after the dyno tuning process is completed. Wade - the man actually building the headers - does not like the idea of an O2 sensor protruding into each of the four primaries, and strongly recommends against installing them. He does find it acceptable to install a sensor in each primary if the bung height is set such that the sensor's business end does not extend into the gas flow path in the primary. Whether we enable Jozef to tune each cylinder individually, or tune the fueling of all four cylinders together, we will have him set up the PCV's gear sensing and optimize fueling for each gear. In pursuit of optimized tuning of the new header, I seek wise counsel from Mohawk, HighSideNZ, CandyRedRC46, MadScientist, and others who have experimented with O2 sensors for tuning via autotune, dyno, or laptop-strapped-to-bike: [1] Would O2 sensors in all four primaries interrupt the exhaust flow enough to be detrimental? [2] Would Jozef's Bosch 4.9 wideband sensors function correctly if their bungs were placed at a height such that the sensor tips did not extend in to the gas flow? [3] Would the advantages of Jozef being able to tune each cylinder's fueling individually outweigh the potential penalty brought by the O2 sensors' position in the primaries? [4] On a Bosch 4.9 wideband O2 sensor, what is the measured distance from its deepest thread point [where it seats against the bung] to the end tip of its sensor? [5] Should I cease and desist attempting to solve a problem that doesn't exist and have Jozef shove a single sniffer down the tailpipe, then tune a single map for all four cylinders combined? Thanks for kicking in suggestions

Here it is...a real header made of real molecules. There are a number of extra welds - especially in the primaries - because this is a built-from-scratch prototype. The welds along the primaries, secondaries, and collector will not be present in the production headers because the bender vendor will be setting up a mandrel to bend all the tubing to Wade's specifications, so he won't have to weld shorter sections together as he did on the prototype. We'll be heading over to pick up the prototype tomorrow afternoon or next Wednesday. We've got the exhaust off of an innocent donor 5th gen and will take the bike to Wade's shop to confirm fitment or make adjustments on site. It was a little nerve wracking that he built straight from the TBR without confirming fitment, but if he's not worried about it, we're not worried about it!