I've spouted a good deal about the Jet-Hot coating of my headers, but before I did all that, I removed the cat shields, opened the canister, bashed the guts out (very difficult to do--they're really in there with beefy bracketry) and welded it back up.
Notice that I cut the O2 sensor shield flange off. I really hated that thing.
I didn't take any shots of the BIG weld bead that is inside each headpipe, right at the flange, but I ground most of that bead away in typical "porting" fashion. I estimate that the inner diameter of that bead ring is about 3/16 to 1/4 inch smaller (total) than the inside of the actual tubes. It is NOT a good location for such a significant restriction. So....if you're thinking of doing anything, and don't feel like gutting, or gutting and Jet-Hotting, or not gutting and Jet-Hotting....at the very least, I would pull your pipes and grind away a good deal of this weld. But not all....it's structural, ya know. And be prepared with serious grinding equipment, because the welds are a VERY hard material and it will be a looooonnnng afternoon for you if you're only armed with a Dremel and those puny grinding bits.
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Shields removed by cutting and grinding and chiseling the spot welds.
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Chiseled spot welds will leave holes to fill. Chalk mark is my cut line. Those full penetration spot welds are where the matrix brackets are welded to the canister.
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Cut open canister bottom with wheel. Man, was THAT noisy!! The cat was really "caterwauling". biggrin.gif
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A view in the cat gut matrix. It's very open to flow, all things considered. The copper colored stuff is a mesh gasket that seals the two matrixes in the canister, forcing about 95 percent of the exhaust thru them but allowing for expansion/vibration. Some exhaust can squeeze by the two modules in the "butt cheeks" area between them without going through for de-smogification.
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Guts are out....poor cat. I really had to beat and pry and "work" the guts out. The brackets are very strong. A lot of it was just bending back and forth until it broke here and there. Took over an hour just for that! Then I cleaned everything up, ground a few snots out of the cat area, and welded it all back together.
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Underside closeup of Jet-Hotted cat. Notice plugs in the O2 holes. Available at any auto parts place..metric oil pan drain plugs is all they are. Forgot the size, sorry.
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Looks good in the sunlight! Meeeoooooowww.... And yes, that is my water-based, two-part, two-coat epoxy garage floor you see shining at you. rolleyes.gif
Does anyone want to buy my original 2000 exhaust (came off my bike) that you see in the background? I bought the set that I did the Cat-Jet work to from a VFRD member so I wouldn't have the bike down for a month while I did all this cutting, welding, Jetting, installing...and in case I "screwed the cat" in the process somehow. I paid $225 for it, because that's what I offered in a Want To Buy posting a few months ago. I'll sell my original set for $175, shipped, Cont. US. It's already packed in the Jet Hot box they sent me my shiny stuff back in, ready to go. They may even give you a break on their $25 (approx) shipping cost, since you already have the box that they would use, and it's a serious box. Then you can sell your original rusty, funky old pipes AND the box to somebody else!
Hey, that was a really good write-up, Trace: informative, easy to follow, well-illustrated, AND entertaining to boot!
Uh.. what's the "O2 sensor shield"? Is that the crap lying next to the zorst in the first pick-a-toor?
Did you consider cutting off the sensor flanges and patching up the pipe to remove some turbulence inside the headers?
Nice job and write-up with all the pics and steps ! Things look real good Jet-Coated . fing02.gif
I still think that this type of Mod won't flow as well as using the 98-99 header set-up, that big can that housed the Cat's has got to mess with flow even though it may not be that detectible. Dropping some connector tubes into the Cat Box should help some. Even the plugged 02 holes will disrupt flow, even if it's minuscule. That's just my opinion though. wink.gif
Thanks for sharing your work ! beer.gif
baileyrock, Dec 15 2005, 08:31 AMDropping some connector tubes into the Cat Box should help some.
'Sfunny, just before I read your reply I was thinking the same thing. WOuldn't be too hard to do, if the flap cut out of the cat was big enough. (Is that a cat flap?) goofy.gif
Iffen I was gonna do this, I still reckon it would be worthwhile ditching it and having a collector pipe made up. But then again, unless you were good with a torch yourself, that would cost some shekels.
enzed_viffer, Dec 14 2005, 02:44 PMUh.. what's the "O2 sensor shield"? Is that the crap lying next to the zorst in the first pick-a-toor?
Did you consider cutting off the sensor flanges and patching up the pipe to remove some turbulence inside the headers?
The O2 sensor shield is a thin aluminum shield that bolts to that little flange thing and protects the outer bits (wires and such) of that sensor from the heat of the oil pan and nearby tube.
[image: user posted image]
O2 sensor shield view As for cutting the sensor bungs, no, I
specifically stayed away from doing anything like that for the express purpose of not ruining the alignment of the pipes to the motor. I was also careful in my cutting and welding of the cat canister, so as not to have the big outlet pointing in some obtuse direction.
I once, many years ago, a young lad with a torch, welded a set of auto headers that I had wiped against a high sewer manhole one night of high speed delinquency. Fixed it on the workbench. Not jigged. Free to move. Free to warp. Needless to say, when I triumphantly went to put my beautifully repaired and painted headers back on the car, they didn't even come CLOSE to matching up the the head ports/bolt holes. D'oh!
However, I did put plugs into the O2 holes that went clear to the bottom of the threads. As for adding pipes inside the cat canister.....you'd have to see it for yourself what it looks like in there, assess the difficulty of doing it right, and consider the Law of Diminising Returns for things like this. Making a 2-to-1 inside that canister might work, but consider that tapering two round pipes to the round outlet in 6 inches of "run" is
very difficult. It might work, or it might not. How would you know? Can't see the wind.......but I do know that the cat "worked fine" with the modules in it, so it stands to reason that it would "work finer" with them out. Beyond that, it's really a Black Box guess. I thought about it too, but chose to not go there.
Trace, Dec 15 2005, 08:37 AMThe O2 sensor shield is a thin aluminum shield that bolts to that little flange thing and protects the outer bits (wires and such) of that sensor from the heat of the oil pan and nearby tube.
Thanx! A picture tells 784 words, and all that.
Did you have to run outside and take that pic?
By the way - I still reckon your bike looks obscenely clean. No way would I post the same picture of my bike. Hmmm... or maybe I will. idea3.gif
Gah! huh.gif
Forgot that I'd need to take the fairing panel off. And looking at the pic, it doesn't adequately show the road spooge, chain spooge, and that strange grime'n'slime that collects on the engine (gremlin spooge?)
Trace, Dec 15 2005, 08:37 AMAs for adding pipes inside the cat canister.....you'd have to see it for yourself what it looks like in there, assess the difficulty of doing it right, and consider the Law of Diminising Returns for things like this. Making a 4-to-1 inside that canister might work, but consider that tapering two round pipes to the round outlet in 6 inches of "run" is very difficult. It might work, or it might not. How would you know? Can't see the wind.......but I do know that the cat "worked fine" with the modules in it, so it stands to reason that it would "work finer" with them out. Beyond that, it's really a Black Box guess. I thought about it too, but chose to not go there.
Looking again at your pix, you're quite right, and the route you took looks like a sensible one. I was just thinking in terms of eliminating that whole horrible-looking 'blob' under the front of the swingarm.
My VF500 had a non-standard collector that seemed to work fine, and that consisted of basically a cylinder with four inlet pipes and two outlet pipes. There may have been some sort of jigger-pokery going on inside it to enhance zorst gas flow or not, but it certainly did the job.
It's quite an inventive solution, but I would have waited for a set of '98-'99 headers.
Anyone have any insight as to why the cat and non-cat headers are arranged differently as to the way the cylinders are paired?
veefer800canuck, Dec 15 2005, 09:11 AMIt's quite an inventive solution, but I would have waited for a set of '98-'99 headers.
Anyone have any insight as to why the cat and non-cat headers are arranged differently as to the way the cylinders are paired?
Do the 98/99 headers pair the front cylinders and the rear cylinders, rather than lefts and rights?
Isn't this something to do with firing order and the monitoring (on the cat headers) of zorst emissions? Perhaps, given that the O2 sensors really only come into play at low(ish) revs, it gives the ECU an opportunity to use only two sensors to measure four exhaust pulses, whereas if the headers were paired the way they are on the 98/99, the zorst gas pulses would occur too close together. Either way, they could've just about got away with one O2 sensor, or better still used four, and monitored EGO right through the rev range.
veefer800canuck, Dec 14 2005, 03:11 PMAnyone have any insight as to why the cat and non-cat headers are arranged differently as to the way the cylinders are paired?
Looks the same to me, just with a cat instead of a collector.
veefer800canuck, Dec 14 2005, 04:11 PMIt's quite an inventive solution, but I would have waited for a set of '98-'99 headers.
Oh, I'm with ya on that one, but.......
Remember that set of Erion's that came up on ePay about 2 months ago, and we all discussed whether a member should reveal it to the Forum and spoil the plans of others, causing a bidding war?
Well, I was prepared to win that war at almost any cost, and had already put in a bid of $1000 when it was still at $50. I wanted to Jet-Hot a set of real headers, and was prepared to pay.
Then the guy pulled it. So I tracked the bastid down thru nefarious trickery means. He lives in Fredrick, Maryland USA. Talked to him on the phone. Not a VFRD guy. Works at some auto dealership. He sold locally to a guy who made him an offer he couldn't refuse.....about $850.
Then I did the salvage yard inquiry thing for a month or so, looking for 98/99s, because I didn't want the "blob" of the canister. Nuttin'.
So.....how long
do you wait?
So I put out a WTB for any 5th Gen headers, hoping for 98/99s. Nope. So I took a nice set of 2001s that were offered. I had orginally intended to make true headers from the pipes by building a 4-to-1 collector, etc etc, so it didn't
really matter to me what year I got. But reality got in the way, since stock pipes are clearly 4-to-2-to-cat, making the whole thing quite difficult (but not impossible). But you'd have to work with it all on the bike to keep the alignments in check and have a snowball's chance of hitting the muffler outlet. It's REALLY a lot of work if you're not a header builder, which I'm not. After thinking and looking and measuring and having a beer, I decided to remove much of the offending blob by deshielding the cat, gutting the beeeioch, and calling it a day (week, actually).
I figger that sometimes Discretion is the Better Part of Valor. I'm happy with the results, and I don't think I left dozens of horsepower on the table in the process.
Wow, I guess I sold my Full Two bro system to soon. Sold it last year for $400 just for the headers. blink.gif
baileyrock, Dec 14 2005, 05:00 PMWow, I guess I sold my Full Two bro system to soon. Sold it last year for $400 just for the headers. blink.gif
1) Supply of VFR headers available = fixed....and declining. Those who have them keep them.
2) Suppy of VFRs that might want headers = growing. Like me. And you and you and you.
3) Supply of any OEM exhausts available due to guys putting on aftermarket headers = see No. 1 above!!
4) Supply of 98/99 headers available used = 50% of No. 3 above.
5) Call Ron Ayers and order 98/99s = big money for stock stuff, but don't think I didn't think about it.
Whadyagonnado?
baileyrock, Dec 14 2005, 10:00 PMWow, I guess I sold my Full Two bro system to soon. Sold it last year for $400 just for the headers.
Yeah and I sold you my 98-99's for what? $75!!!!! beer.gif goofy.gif Ahh, anything for a bro'. biggrin.gif
chris2992, Dec 14 2005, 03:38 PMLooks the same to me, just with a cat instead of a collector.
Oh, I looked and you are right, '98-'01 cat or non-cat pair the two left cylinders and the two right cylinders before merging.
cat:
http://www.ronayers.com/fiche/200_0366/muf...2/muffler_2.bmpNon-cat:
http://www.ronayers.com/fiche/200_0366/muf...1/muffler_1.bmpIt's the VTEC models that route the exhaust differently.
http://www.ronayers.com/fiche/200_0408/muf...2/muffler_2.bmpIt looks to be pairing front left with right rear and vice versa (if I'm staring at the drawing correctly).
I still wanna see someone slap a SS TBR header for a 5th gen onto a 6th gen with some "Frickin' Lasers"! wheel.gif
Oh yes, now I remember the other reason to use the 98-99 headers, there larger tube dia. 43mm vs 45mm. After market tubes are even larger. blink.gif
I was wondering if Honda made the tubes smaller on the CAT bikes to increase pressure, helping it's path through the CAT. Or is that just wrong ? unsure.gif
but from looking at Ron Ayers site, you can purchase cat and non cat pipes for the 5th gen years so are we to assume the non cat pipes are 43mm too or assume they are 45mm like earlier years? hmmm
veefer800canuck, Dec 14 2005, 04:28 PMOh, I looked and you are right, '98-'01 cat or non-cat pair the two left cylinders and the two right cylinders before merging.
It looks to be pairing front left with right rear and vice versa (if I'm staring at the drawing correctly).
I still wanna see someone slap a SS TBR header for a 5th gen onto a 6th gen with some "Frickin' Lasers"! wheel.gif
Actually it looks like the Ron Ayers pics are wrong and all CAT equipped headers do a over/under cross of the front two pipes, where the 98-99 front tubes are parallel.
Look at Trace's last pic with the two systems side by side and you'll see that they both have crossed front tubes just like a Vtec system. fing02.gif
Don't trust a drawing! cool.gif
baileyrock, Dec 14 2005, 04:11 PMActually it looks like the Ron Ayers pics are wrong and all CAT equipped headers do a over/under cross of the front two pipes, where the 98-99 front tubes are parallel.
Look at Trace's last pic with the two systems side by side and you'll see that they both have crossed front tubes just like a Vtec system. fing02.gif
Don't trust a drawing! cool.gif
don't they both have crossed tubes because they are the off of the same year bike and both have cats?
teleskier, Dec 14 2005, 05:13 PMdon't they both have crossed tubes because they are the off of the same year bike and both have cats?
Yes, but Ron Ayers shows the CAT 5th gens (2000-up) as parallel which they are obviously not ! fing02.gif
gottcha...sorry for the confusion
teleskier, Dec 14 2005, 05:08 PMbut from looking at Ron Ayers site, you can purchase cat and non cat pipes for the 5th gen years so are we to assume the non cat pipes are 43mm too or assume they are 45mm like earlier years?� hmmm
No, all CAT tubes are 43mm, I just happen to have all 3 sets. beer.gif Only the 98-99 non-CAT headers are 45mm and will bolt right up to your 5th or 6th gen Viffer. fing02.gif
baileyrock, Dec 15 2005, 11:29 AMNo, all CAT tubes are 43mm, I just happen to have all 3 sets. beer.gif Only the 98-99 non-CAT headers are 45mm.
But it doesn't necessarily mean that smaller is worserer, like when Honda-san dropped the carb size 2mm form the 3rd gen to 4th gen.
enzed_viffer, Dec 14 2005, 05:41 PMBut it doesn't necessarily mean that smaller is worserer, like when Honda-san dropped the carb size 2mm form the 3rd gen to 4th gen.
You are correct my friend ! But Mr Honda-san designed the 5th gen with 45mm tubes until they added a CAT in 2000.
In general smaller and or longer tubes promote low end or torque and larger and or shorter tubes will allow more gains at higher RPM's. It affects Cylinder scaveging(?) and many other things . It all depends on what power you want where. comp13.gif
baileyrock, Dec 15 2005, 11:51 AM It all depends on what power you want where.
I want BIG power, and I want it at my right hand. comp13.gif
Axe Shirley, I ride in the Real World ™ so if I had to choose, I'd have some of them torques, and I'd have them where I do most of my riding, which is below 6K rpm.
I miss my VTR! sad.gif
But only for the low-down torque hit. The VFR is better in most other ways, and purtier. 491.gif
enzed_viffer, Dec 14 2005, 05:59 PMI want BIG power, and I want it at my right hand. comp13.gif
Axe Shirley, I ride in the Real World ™ so if I had to choose, I'd have some of them torques, and I'd have them where I do most of my riding, which is below 6K rpm.
I miss my VTR! sad.gif
But only for the low-down torque hit. The VFR is better in most other ways, and purtier.
Word !
I too would like torque, I'd take 20 lbs of torque over HP any day ! If I had to choose anyway! wink.gif
Trace,
Thanx, Haus! That was the ticket. Still haven't found 98-99 pipes, and this is cheaper anyway.
baileyrock, Dec 14 2005, 06:01 PM I was wondering if Honda made the tubes smaller on the CAT bikes to increase pressure, helping it's path through the CAT. Or is that just wrong ? unsure.gif
Nahh.....kinda wrong. Acutally, the smaller tubes would add to
backpressure a wee bit, thus decreasing total pressure at the cat. However, the velocity would go up a bit in the pipes themselves. [there's that inverse ratio again!] But in looking at the cat matrix design, it's just NOT scienced-out in some "shoot the higher velocity gas thru the matrix faster" manner. The exhaust arrives at that big can and slows down a bunch. And sees less flow loss (i.e. backpressure) due to that lower velocity. Or....it could be the opposite: The cat reduced total flowrate, thus a smaller, lighter, cheaper tube could be used. Or....Honda got a good vendor price on the smaller tube and went with that! It's really hard to say definitively, since
we can't see the wind....
But yeah, I would have prefered the larger girth of the earlier model tube, fer sher.
Hmmmmmm, wondering, if a decent backpressure could be achieved, at the cat housing, (with a baffle), so one could run straight pipes the rest of the way back. A P.C.III, K&N, then scream along. ????
Rivcyko, Dec 14 2005, 08:10 PMHmmmmmm, wondering, if a decent backpressure could be achieved, at the cat housing, (with a baffle), so one could run straight pipes the rest of the way back. A P.C.III, K&N, then scream along. ????
Well, dunno....but as I mentioned, my bike went lean when I put the gutted-but-otherwise identical set of pipes on. So....the cat guts are certainly adding their own hinderance to flow, in spite of their generous sizing and open matrix. As for adding baffles, going straight, etc......you're own your own!! 491.gif
Trace, Dec 14 2005, 06:28 PMHowever, the velocity would go up a bit in the pipes themselves.
But yeah, I would have prefered the larger girth of the earlier model tube, fer sher.
It's the idea of increased velocity that I was trying to get across. Higher air speed when it hits the CAT and slows again. unsure.gif
Keep up the good work ! wheel.gif
Here is my question how much did the matrix weigh when you removed it??
How much weight did the coating add to the system?
Synaptic Misfire, Dec 15 2005, 05:34 PMHere is my question how much did the matrix weigh when you removed it??
How much weight did the coating add to the system?
Synaptic-
You're kidding, right? You've GOT to be kidding. I didn't before/after weigh the headers before I sent 'em to Jet-Hot. I wasn't thinking about the weight of coating...I just wanted 'em to look purty.
Okay, okay....here goes....the removed matrix weighed about 3 lbs total. The coating weighed about.....3 lbs. No..that can't be right. The the coating weighed...the same as thick paint plus 5%? Whatever that weighs. One pound. No...too much. But then, I removed those weld beads inside each header. That was....a teaspoon of iron filings. And then there were the cat shields removed. And the O2 sensors....but I added the block-off plugs back in. And I added a lot of brazing rod. But I cut that little O2 sensor shield flange off. And I added the weight of the Power Commander and the shift light.
I have no idea.
Ok I was kidding about the coating. But 3lbs. of weight is significant loss from the matrix.
Thanks for the great info and pics, I am laid up at the moment and cannot ride I might be tackling this over the weekend and next week or so.
Yeah, I'd say that when you remove all the stuff, there's 3 lbs of it. But no more, I'd say. And there's about a pound of dirty sooty crud that will end up in your garage floor. sad.gif (I recommend a bag of mulch as a workbench, in your yard. Nice and stable "platform" as you wrestle the pipes, just like a sandbag for a sharpshooter!! Notice the bag in my pictures. Topsoil. Mulch would have been better. The NEXT time I do this...it's mulch for me. Now, I haven't decided on the BRAND of mulch, or whether it's shredded pine bark, nuggets, cypress, or that tacky colored stuff. I'm going to post a poll--What Mulch Do You Use?)
And you'll lose 3 lbs of sweat wrestling those damn cat-guts out of the canister in the Florida warmth.
Damn...that reminds me...I leave warm, sunny Ponte Vedra Beach in the morning, headed for cold, snowy DC. Brrr.....
Gotta go pack.
Puh-leeze do your VFR a favor and use 50wt synthetic mulch.
FotoMoto, Dec 15 2005, 08:34 PMPuh-leeze do your VFR a favor and use 50wt synthetic mulch.
tongue.gif tongue.gif tongue.gif
And a dollar for HS: +1
enzed_viffer, Dec 14 2005, 01:42 PMand that strange grime'n'slime that collects on the engine (gremlin spooge?)
Actually that's Kong spooge (not to be confused with Hobbit spooge), found only in New Zealand. We're spooge-free here rolleyes.gif
End of thread · 38 posts recovered Wayback Machine snapshot 21 Feb 2006
