?? The coating process is a bath. Both the inside and outside get coated, everytime. Think of dropping a plumbing pipe into a lake. Both the inside and outside of the pipe will get coated with water. You've got quite a hot spot if you are burning through coated headers, and your engine error codes suggest looking into a core problem that will no doubt destroy any installed headers and probably lots more things ala valves, cats, etc.
Thanks. I didn't know this. Especially since I was asked specifically whether or not I wanted to coat the inside and out, or just the out. --nick
Bizarre. They would have to cap the ends of each header tube to *prevent* the coating fluid from going inside when the pipes were dipped if you didn't want the inside coated for some reason. Are you dealing with reputable sources?
Fabspeed. They came highly recommended by fellow f-chatters. As far as potential underlying engine problem causing hot-spots; I recently had my Ferrari dealer give a thorough examination of my car to ensure that it wasn't producing excessive heat. They had my car for 5 weeks and my permission for the tech to drive it as his personal car during the analysis. In the end, everything pointed to bad catalysts (Hyperflows). Not that they were clogged, but that they're not converting properly. In addition, the 1448, 1445, and 1449 cels appear if idling for 6-10 minutes in which case the slow-down light starts to blink. Temperatures were measured while this light was blinking, but according to the tech, temps were within spec. Driving makes the slow-down light stop blinking. I'm really starting to suspect that some peeled, internal ceramic coating (due to poor workmanship or simple thermal expansion properties of stainless steel) has ruined the catalyst properties of my Hyperflows, which in turn could be causing these cel's which appeared within 1.5 weeks of the header installation. Can this coating simply be removed (inside and out). I think I prefer to remove the coating all together considering I have installed the fabspeed alternator and compressor shields as well. Perhaps I'll simply wrap them in some sort of header wrap rather than coat them again. Thanks, Nick
In the UK, there's a company called Zircotec that does the heat resistance coatings. When I last enquired the cost was around £270 i think for a set o manifolds. Lamborghini use one of their coatings for the Reventon http://www.zircotec.com/
I though the aux. air pump only operates for a few minutes after start-up with a cold engine? Does it run more often than that? Is the extra air an issue/problem if the cats. are removed? How do you cap the air injection manifolds on the headers if you remove the air injection plumbing? Are there threaded caps, that big, available to close off the manifolds?
Sorry to hear about some of the problems with the coating... I've had my Fab-speed headers on for about 1.5 years and over 8k miles. They were coated by Jet-hot inside and out with the highest rated coating they have. I've had NO problems since install... they show NO sign of cracks or discoloring!
I measured my header temps today (engine-out process starts tomorrow) after about 45 minutes of driving. Each side measures almost identical in temps. On each side, runner 1 measures about 660 degrees F, runner 2 about 790, runner 3 about 580, and runner 4 about 580. I thought the high temp at header runner two (piston 2 ?), passenger side, being so much higher than the others was abnormal. Then I measured the driver side and got the same results. So, I doubt my coating is peeling because of excessive heat. More than likely the passenger side header was just poorly coated. --Nick
Temperature, like you are relating, are representative of part throttle operation, only. They represent no stress at all in the world view of headers. The minor differences are probably cyclinder to cyclinder idle gas mixture+timing isues. THe ECU will sort this all out by itself, given enough time at the thorttle positions and RPMs you are running. The temperatures at which real interesting thing start happening is above 80% throttle for minutes at a time. The gasses leave the combustion chamber near 1700dF and arrive at the header near 1600dF and at the collector near 1200dF. Thats a lot of heat to loose in 3-odd feet. The speed of sound in the gas mixture changes speed with the temperature of the gas. The speed of sound is how the pressure waves are utilized in the header to make power. Now, once the gasses reach the CAT, the temp goes back up into the low 2000dF range where the bad stuff is converted to less bad stuff. Metals in this kind of temperature environment have very little strength. {If you have seen a set of blown headers, you might be surprised at how often the tubes are blown INWARD. This occurs because the now hot metal has just passed a larger (~70 PSI heat pulse and gone up 30-40dF, just over its strength range, then the big neagtive pressure wave come up the pipe and presto, the header collapses inward! So the headers are tremendously efficient at getting rid of heat by passing it into the air and by radiative trasnport. So efficitne that they don't really have a stable temperature--even at 8000 RPMs--but I digress} If you hold in the heat (with coatings or header wrap), you speed up the gas flow. This changes the header timing towards higher RPMs, and you loose low RPM Tq around the point where the header comes into tune with the cam. Thus, if you want the heat gone, and the Tq to stick around, you need a longer set of tubes, and a slightly longer expansion chamber (which these cars do not have--but that is another story). I have gotten out of my car in the evening after a long run on the race track, and I can see the tremendous heat (dull cherry red) comming up out of the engine bay as the headers shed heat. This is another reason to do a cool down lap {I have also seen glowing rotors in the cool-down pits. One Texas summer we could almost roast hot dogs by the heat from the rotors. It would have been no problem to roast them on the headers--all while sitting in the pits with the engine off. So, the only real way to get the header temps is to have the temp reading device able to see the temps while you are running the snot out of the car on the track (or dyno). Othersiwe, you are just looking at remnants and wondering.
Awesome details there, Mitch! Thanks! I've learned a lot from that post Nevertheless, based on what you've explained, I think that based on how I've driven the car since the header installation (not hard as you've described, not long as you've described, and not often at all -- driven only for 45 minutes once every two to three weeks); the headers were definitely coated improperly. In other words, I'm sure that if what you've described is what it takes to get the temps up to what you've detailed, then my car hasn't seen those temps since the headers were installed. At least not nearly enough for the coating to have peeled in such a short period of time, right?? We'll see what happens after Swain Tech finishes with them (white lightening). I've decided to just have them recoated at my own expense. Thanks, Nick
If I had to guess, and it's *only* a guess, I'd say the treatment that preps the surface prior to coating is suspect. It really sounds like an adhesion problem, not a temperature problem. I had a local vendor (formerly Airborn Coatings) coat my Fabspeeds and they look absolutely fantastic after a few thousand miles (with quite a bit of time at 8000 rppm ) The same shop coated my STi headers maybe 4 yrs ago and they still look great. Here's a link to what I have: http://www.airborncoatings.com/alumcerm.html For 355 header temps, I've measured about the same (500-700F) but I agree with Mitch, it's not that useful because the car isn't running, depends on if the fan just kicked on, outside temp, etc.
If the engine is a good running engine with proper A/F ratios, the catalytics should not get much hotter than the exhaust temp going in ...... if they do get a lot hotter ...... there are excess hydrocarbons in the exhaust. These are catalysts not thermal reactors. http://www.aa1car.com/library/converter.htm
HI It is Joe @ Fabspeed Motorsport USA If your header coating or any header coating is peeling that fast then Jet Hot or that coating vendor did not do a proper job of prepping the surface for coating. Coating companies abrasive media blast parts to get some "tooth" for good adhesion. Headers are dry powdercoated with the header companies proprietary super heat coating and baked/ cured in a special oven. Your 355 Fabspeed headers (2.7 or 5.2 version) and all my 355, 360, and 430 headers are 16 guage 0.065 wall T 304L USA stainless steel and gas purge tig welded. Fabspeed C.N.C. mandrel bends all V8 header primary tubes in 1 continous piece for maximum exhaust flow. Any and all internal welds and ground and profiled for maximum exhaust flow. I even lost wax investment cast the inlet flanges in T304 stainless steel and added EGR ports. Ferrari 355 headers were manufactured from very thin walled tubing and welded up from many variuos "J bends and U bends" almost in a hobbyist manner. All these welds and very thin header tubes are the reason why the headers are failing. Ferrari headers carry and support alot of weight and the extremely thin walled construction and sloppy welds will always conspire to failure. It is embarrassing. Given the extremely thin header material and welded base materials "fixing and patching the existing OEM headers" is a waste of time as you are fixing and refixing parts that will contue to fail. I have cut up many failed sets and the tubes are caved in and cracked in several parts on the same header. You would hear exhaust leaks and "ticking" if the headers were not wrapped. Look for black soot coming out of the stamped heat shields for leaking headers. People should know that 304L stianless steel is a very poor conductor of heat compared to regular header materials. This in of itself acts as a heat shield. Fabspeed makes heat shields for the 355 and 360 cars that are easy to install and adress any concerns you may have. I have had headers on many customers cars for years in Arizona with no heat shields and we have had no issues whatsoever. Now we have developed heat shields for the A/C compressor and alternator and these are available for any brand of header too. I personally dont feel header coatings are necessary for Ferrari headers. Many header manufactures also state that coatings VOID the header warranty as do heat tape wrappings. Fabspeed headers were designed to maximize horsepower and torque and have a high velocity merge collector as used in F1, Indy car, and Nascar. Before and after DYNO testing same day and same conditions on a 1997 355 netted an addition +17HP at the rear wheels which is +19.55 at the crank (+17HP X 1.15% drivetrain loss = actual crank engine power). So when your F355 headers need to be replaced or you want additional power............ I think we did a great job designing a product that will not fail, wont heat or harm any components, bolts-on easily in the car, and adds close to 20HP. Everyone is invited to cruise over to Fabspeed to see our headers and if you would like I would send a set to Dave Helms or anyone that would like to see and hold a set. I have a question.........I manufacture these for 355, 360 and 430.........do the 348, 328 cars have issues with their headers? For Ferrari 355 Video explanation goto http://www.fabspeed.com/ferrari_355.html click on ** VIDEO ** -> Ferrari F355 Headers Explanation & Dyno Run Have a great weekend.
I love my Fabspeed headers. I even have the optional heat shields and the Fabspeed y-pipe. I'm just not happy with the coating (peeling). Even if coating is unnecessary, it shouldn't hurt to do so. As it turns out, Fabspeed had my 5.2 headers coated by their preferred vendor, Central Connecticut Coating, before they were shipped to me. Jeremy at Fabspeed has pics of my peeled headers. He's instructed me to send the headers back to CCC, but I think I'll eat the cost and have Swain Tech use their white lightning coating instead. The peeled coating on my headers looks 'pretty' thin. Now, you asked about 348s and 328s. How about 612's?? I have an 05 612 Scaglietti as well. Do you intend to make any exhaust performance parts for 612's? The most I can find right now is the muffler section; I'm going with Larini. I'd like to replace the center resonators with straight pipe as well as have high-flow cats. The 612 is REALLY bottled up in my opinion. It's also one of the quietest Ferrari's I've ever heard. Can't have that!! Thanks, Nick
348 OEM exhaust headers are fine. Probably thicker than 355 headers, with less heat/flow from the engine. Room for improvement in the 348 cats, but the Spider muffler is decent straight from the factory, as well. Ferrari was desperate for *any* weight savings on the 355 after adding air bags, power seats, power tops, power shocks, power steering, F1 hydraulics, larger engine, more transmission gears, an exhaust bypass valve, heavier valvetrain, more belts, and a host of computers onto the 355 package compared to the 348...so the exhaust headers went on a diet.
Hey don't forget that the 355 revs 1000 rpm higher and sucks much more fuel up to generate power and cool down those cylinders. I am so glad I cannot possibly relate to this thread because I drive a lowly underpowered unwanted (and apparently cooler) 348. And yes we swapped goth's headers doing just what Bruce described. Raised car, dropped wheels, undertray, removed fans and that pesky passenger's side oil can. It barely dropped oil too so no worries about huge puddles on the garage floor. i think it was about a quart that we lost, eh goth?
