So I was thinking, is this a good idea?
I might get a slip on one of these days and I had the idea of instead of just painting it, why not tack weld it and send it off to be ceramic or jethot coated? I have a few other things I need to send off to be coated, so I might as well have the entire exaust system (minus the can of course) also coated. If you're not familiar with ceramic coating, what it does is it keeps the heat inside the exhaust plumbing causing the exhaust gasses to move faster and thus flow better.
I'd bet it would gain me a fraction of a hp, but a gain none the less. I also suspect it would make things run cooler, but that's only a guess.
Has anyone tried this? I couldn't find anything when I did a search, so I'm sorry if this is one of those regular topics and I'm just an idiot.
It works and looks good with cars, why not bikes!
The advantage of the pipe not being as hot to touch when you bump it changing your oil is another benefit. :thumb:
Far as I know it's one of the most durable coatings you con get for the headers, but still not completely rain-proof.
Galahs: Next time you change your oil let the motor cool off for a quarter hour after running it well hot. Headers are cold then, but the block still well warm.
Quote from: galahs on April 12, 2006, 08:46:30 AM
The advantage of the pipe not being as hot to touch when you bump it changing your oil is another benefit. :thumb:
or when you're clumsy like me and manage to bump into it for no reason at all :icon_lol:
another thought I had is a lot of these coating comes with a lifetime warranty against corrosion, so no more rust :thumb:
I'll have to give it a try and see how it goes... now the question is what color? black? chrome? hmmm....
Black will radiate (loose) heat the fastest. So for performance white or chrome.
For looks, Black or Chrome.
thats a good point, so chrome it is!
Quote from: MarkusN on April 12, 2006, 08:52:56 AMbut still not completely rain-proof.
Care to elaborate? I thought they coated the inside...
I don't know much about it other than it helps keep the heat in the pipes.
you can actually get cermamic coating for the inside and/or outside of your exhaust pipe.
Some say doing the inside makes for a smooth passage over joins etc.
If you could get it in black (or chrome if you're into that) and it wouldn't chip off, rust, etc... It might be worth the investment.
Plus, you'd never have to worry about melting your front fender. :thumb:
no after u coat it, would it end up looking like one of those micron exhaust? or wuld u have to paint it?
after its coated it will have a nice finish, either black or chrome, or even other colors are availible. so no there is no need to paint it
nice, when are u planing on doing it?
I dunno, I haven't even decided if I really want to get a slip on yet... I have some other things that could use some ceramic coating, so whenever I feel like blowing some cash and getting that done, I'll probably get the GS done too.
Ceramic coating for performance value on a bike is kinda not worth it. The bike exhaust for the most part is exposed to air which is cooling it anyway. A ceramic coating at this point is just bling. In my experience with turbo car applications, ceramic coating is great for keeping underhood temps down. However, this could also be achieved with much cheaper heat wrap.
With this being said.... I think for looks a good high temp engine paint will look good and cost much less than a JetHot/Ceramic coating.
-Drew
Ceramic coating does a lot more the keeping underhoop temps down esp in a turbo application. It keeps the gasses moving faster and helps evacuate the combustion chamber quicker. In a turbo application this also means less turbo 'lag'. Not to mention it is a lot better at preventing corrosion on mild steel pipes then paint. And unless this is for a well funded race application where replacing the exhaust manifold after every race is an option, header wrap is a no-no
I understand that loss of heat/energy in turbo applications is key but when we are takling about "lag" and "evacuating combustion chamber pressure" I find that ceramic coating is pretty much unnecessary. (This is what 3 or hell... even 4 inch downpipes are for.) Personally I run a 2.5 inch downpipe to my exhaust. (I also have the option of opening my downpipe cutout which is only a foot or two rear of the turbo itself)
corrosion will happen with paint yes... but at the cost of a ceramic coating I could never justify it on one of my setups. Also I don't see what is so wrong with heat wrap. You hardly need to change it after every race... that is a bit exaggerated. I actually know a few SFWD cars that use heat wrap... and they have sweet looking manifold... almost a shame to cover them up.
It seems you are set with getting it ceramic coated... I'm definitely not ripping on ceramic coatings.. its pretty sweet. But in this situation I don't think any gains short of cosmetic gains are to be had. :cheers:
I don't have my heart set on it, it was just a thought because I need my manifold, turbine housing, and downpipe ceramic coated, why not have my primary pipe coated too?
The problem with just using bigger downpipes or cut outs (unless of course its a boost activated cut out :thumb:) is you lose back pressure, which creates even worse turbo lag and loss in low end performance. Ceramic coating can increase the flow rate of piping just like you would by using larger piping, but without these negative side effects. The heat retention characteristics of the piping are just as important to flow as size, and are a big factor in material selection by OEMs and race teams for their exhaust systems.
As for header wrap, it can cause heat soak and tempurature variations in the exhaust manifold which can cause cracking in a tubular manifold. Remember, ceramic coating goes inside and out evenly, whereas wrap is only on the outside and isn't very consistant. Also, in street uses, it can soak up water from the road causing even more severe tempurature variations. Someone once told me they used to use header wrap in NASCAR, and they would crack headers almost every race. I have never used it, I have always been told to never use it, I don't mean to bash it if it works for you, but I just want pass along the advice I've been given.
As for performance gains with the GS I dunno :dunno_white:
but I would bet there would be enough gains to warrant the ~$100 it would cost
:icon_razz: No such thing as too little back pressure in a turbo exhaust situation. Hell, the only reason to use an exhaust behind a turbo is to get those gases away from the engine bay and to possiblely keep the noise down/away from the cabin. I have run open downpipe at the track and on the street for years... open downpipe results in near instantaneous boost not lag. The sound of turbo spool with my downpipe open is so fast and loud that is almost abnoxious. Normally with full exhaust I hit 10lbs @ a little under 4k with open downpipe I get full 10 at a little under 3500.
As far as heat wrap causing failure because of inconsistant heating and cooling... never heard of it. Perhaps if the manifolds were made of 16 guage mild or thinner. I have seen Sch10 and sch40 exhausts reach red hot temps for sustained periods and have no problems with heat wrap.
Anyway.... as far as ceramic coating being 100 bucks... I guess why not... it'll look cool. But really for a 100bucks (provided you can tig) you could get mostly all the resource you need for a full stainless (minus the muffler)
you honda guys :cookoo:
You know what, you're right, turbo lag is reduced by reducing restrictions. Duh. I don't know what I was thinking, I must have been away from the turbo too long. My turbo spools slightly faster without a cat then with a cat. But, it also has better off boost performance with the cat. I don't have the most street friendly turbo, and added restrictions do make a difference for that <3k NA torque in stop and go traffic. I'll have to try running an open downpipe and see what that does.
Nevertheless, I'm sure ceramic coating the primary on the GS will do more then just look cool. Looking around it seems ceramic coating MC exhausts is a somewhat common performance mod.
If you don't believe me about the header wrap thing, go down to a good speed shop and talk to the guys there. Every person I've talked to in the racing biz has had nothing good to say about it. Or do a google search for header wrap, you'll finds loads of sites and forums saying don't use it. It's just one of those things that's been beaten into me.
my virago had MAC ceramic coated headers in glos black. they looked great the nine years i had them. sounds like a good idea go for it. see ya.
:flipoff: you love us Honda guys. (lol, funny because... i hate most Honda guys :laugh:)
Good thread here guys! And it turned into a turbocharger conversation which is near and dear to my heart!
Unfortunately, too many people seem misinformed about "back pressure" in regards to IC engines. Not only is back pressure a bad thing for a turbocharged application, but there is no case where back pressure can positively influence the performance of an internal combustion engine. When discussing a large diameter exhaust, many people claim that "you will loose too much back pressure". This is usually thought to hurt the low-mid RPM range of an engines performance and help the high RPM range. In fact, switching to an overly large diameter exhaust pipe will lower the exhaust gas velocity. This is where your low-mid RPM performance is lost. The higher velocity exhaust gasses produce a "scavenging" effect in the cylinder which aids in the evacuation of exhaust gasses at these lower RPM's. If the diameter of the exhaust pipe is enlarged beyond a certain point, this scavenging effect will be deminished or lost, thus hurting low end power. Scavenging effects are non-existant in higher RPM ranges, so in this instance, the more air you can flow...the better.
Remember high school physics class? If you keep the volumetric flow rate the same through a peice of pipe and somehow enlarge its diameter (and thus cross-sectional area), the velocity will slow. The flow rate near the exhaust valve pulses (as the valve opens and closes). The exhaust gasses further down the exhaust pipe do not pulse as much mainly due to pressure gradients in the exhaust pipe. When the exhaust valve closes, the exhaust gasses further down the pipe are still flowing. This causes a slight pressure drop near the valve and the faster the exhaust gasses are flowing in the exhaust, the greater this pressure drop will be. Once the valve opens again, the exhaust gasses in the cylinder are generally at a higher pressure and will be scavenged (or "pulled") out of the cylinder at a slightly faster rate than they would be of only pushed out by the piston.
Alright, I'll shut up. Horray for geeks like us!
-Turd
;) not a bad writeup Mr. Ferguson. :icon_razz:
Alot of exhaust wraps, accelerate corrosion of the pipe.
The advantage of ceramic coating:
- reduces chances of corrossion
- helps chanel heat out the tail pipe. Hotter gases flow better meaning better performance, keeps your faring (if you have one) from getting too hot, and (especially if its not black) less heat will radiate from the exhaust piping heating the oil pan more.