EMWHYR0HEN Posted January 1, 2007 Share Posted January 1, 2007 I guess your big question now is, what can you do to prevent this from happening again? Consider : Ignition timing, compression and boost pressure, fuel octane, and maybe an air filter? hope all goes well. Quote Link to comment Share on other sites More sharing options...
240hoke Posted January 1, 2007 Author Share Posted January 1, 2007 Yup OTM its a P90. Quote Link to comment Share on other sites More sharing options...
jt1 Posted January 1, 2007 Share Posted January 1, 2007 That's detonation damage for sure on the head. Did you have anything shot peened or shot blasted? The shot blasting I've seen used a lot smaller shot than the dimples, but there may be different sizes. Was the other ceramic coating OK, or was it coming off too? John Quote Link to comment Share on other sites More sharing options...
dalesince59 Posted January 1, 2007 Share Posted January 1, 2007 The damage on the piston dome and head surface was caused by detonation .The severe scoring on the piston skirts shows it was caused by thermal expansion due to an overheat condition in that cyl. not by any side loading issues. dale Quote Link to comment Share on other sites More sharing options...
RB26powered74zcar Posted January 1, 2007 Share Posted January 1, 2007 Soon as I read that the top ring land had collapsed, my first impression was detonation. . Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted January 1, 2007 Share Posted January 1, 2007 DOH...I had always thought the P90 looked open like an E88 but just a taller roof...I guess I'm just an ignoramus...lol Quote Link to comment Share on other sites More sharing options...
510six Posted January 1, 2007 Share Posted January 1, 2007 I feel your pain..when my motor went lean under N20 it fried two JE pistons and damaged a ultra rare N33 head.My solution was to upgrade my engine managment and dattalogging capability and be very conservative in my initial tuning. Quote Link to comment Share on other sites More sharing options...
woldson Posted January 1, 2007 Share Posted January 1, 2007 Frist of all cermaic coating is great, i reducses the chance of ping, my friend with the 805 rwhp had a BAD timing issue dyno guy said he was running dieasal pressue in the cyls. Small amout of det damage. Olny tinge that save that engine was the coating. Also the coating did not break down like it showed on yours. that coating shows that what ever it was suck around for a long time to shot peen all that coating away. My bro just fried two rebuilds on his honda the ring lans on the intake where its the hottest broke, this was frm boost creep. On the other side how the hell did that object stay in there so long with out being ejected? and how did i so servive that type of abuse????? cant believe welding slag.......... This is quite the cojitator. hmmmmmmm Quote Link to comment Share on other sites More sharing options...
240hoke Posted January 1, 2007 Author Share Posted January 1, 2007 I politely disagree, the ceramic coating is worthless. Its destroyed on all my pistons not just the FOD one. Got the motor back together, cant wait to get it on the dyno, prolly be a little while though as im going ot work on my tranny adaptor before I put it back in. Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 1, 2007 Share Posted January 1, 2007 I'm going to have to butt in here and say something about coatings, in light of what or where this thread has turned. First, coatings ARE prven quantities. Ceramic Coatings in particular. Similar to the "splitfire spark plug arguement" there are documented testing that was done on fully instrumented engines that prove their efficacy. PROBLEM IS THIS: Many times people jumpp on the bandwagon and start slapping stuff on pistons as a revenue generator. Application of the coating is almost MORE IMPORTANT than the coating itself. No matter how GOOD any given coating is at this or that, if it is not applied correctly it will crack off and peel away in short order! This MAY be the case in Austin's engine, but for Austin to start making blanket statements that "ceramic coatings are worthless" based on anecdotal evidence found within his engine is just plain wrong. What may be more correct is for Austin to say the coating he chose was worthless, or even more correctly, the application may have been incorrect. I have Swaintech coated pistons in both our Bonneville Cars, and can attest to some oil temperature reduction, as well as protection of the piston head during some tuning miscues. Remember if you were detonating, you were tuned wrong, and there lies a source of massive and well over-specification pressures that can cause flaking of shoddily-applied coatings. All I'm saying is nobody should be making blanket statements based on this example. It's wrong, and FAR from scientific---there are MANY things wrong with this engine. Flaking of piston coatings is a symptom, not a cause! Quote Link to comment Share on other sites More sharing options...
240zV8 Posted January 1, 2007 Share Posted January 1, 2007 what did the spark plug look like on that cylinder? can u post a pic? Quote Link to comment Share on other sites More sharing options...
dalesince59 Posted January 1, 2007 Share Posted January 1, 2007 I politely disagree, the ceramic coating is worthless. Its destroyed on all my pistons not just the FOD one. The real question on the coating issue should be ,what the damage would there have been without it? I have used flame coatings on pistons since the late 1970's with always positive results. You must remember that most coatings are there to protect the material and provide a "time" barrier against damage. the coating on the pistons will slow down the damage process not necessarily prevent it entirely. dale Quote Link to comment Share on other sites More sharing options...
240hoke Posted January 2, 2007 Author Share Posted January 2, 2007 I agree tony, and I will say that perhaps I got a bad batch. The head has minimal damage. The plugs also look great, just black. The electrodes are not burned or misshapen at all, not do I see any metal flakes on them. Shes put together now, and I plan to do all my tuning on a dyno to get my timing curve right this time and tune in more controlled circumstances then on the street. I plan to install meth and take it to 25psi. See yall at SEZ Quote Link to comment Share on other sites More sharing options...
240zV8 Posted January 2, 2007 Share Posted January 2, 2007 I agree tony, and I will say that perhaps I got a bad batch. The head has minimal damage. The plugs also look great, just black. The electrodes are not burned or misshapen at all, not do I see any metal flakes on them. Shes put together now, and I plan to do all my tuning on a dyno to get my timing curve right this time and tune in more controlled circumstances then on the street. I plan to install meth and take it to 25psi. See yall at SEZ I was gonna say maybe the electrode broke off somehow and caused all those dimples, but very very doubtful. I guess you burned up whatever caused it. Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 2, 2007 Share Posted January 2, 2007 Yeah, reading the PRI issue last year relating to "Marketing Potential in Coatings" I thought "oh no, this isn't good!" Guys start marketing stuff they get at jobber prices at markup with no time of effort expended on their part---pure profit on something with almost a 100% chance of NOT ever coming back as a warranty item! I limit my coating sources to well-known application shops like Swaintech. In the PRI article, you could see a ot of the business that had been in it for some time always stressed proper application (both in getting the surface prepped correctly, as well as choosing the right coating for the environment for which it is being chosen.) I know when I got ceramic coating applied to stationary ICE's, the results were startling---then again, this was almost 17 years ago now (early 1990's)---at that time ceramic coatings were exceedingly thick, and you had to ship parts to the manufacturer to get them coated as there were not a lot of places to get it done. Aerospace Black Art is what it was back then! We had very good luck in extending valve life on heavily turbocharged natural gas powerplants using sour corrosive feedgas, as well as lowering oil temperatures and decreasing fuel consumption markedly. I'm talking in the order of over 75,000CF/D per powerplant. Heat rate (power produced per BTU Consumed) on the engines went markedly better after coating. At the time, our generation curve was low, and we were pinched for feedgas, so we ended up doing all three generators with this coating. At the same time, the Splitfire plug was new on the market, and they were good for almost 50KCF/D on top of the other gains from the ceramic coating---but they just had their electrodes eaten up too fast to make them economically viable. The OEM was very interested in our treatments, but they didn't want to segregate their core stock between coated and uncoated cores. Ultimately they didn't incorporate it for this and the intial costs involved...then they phased the unit out of production. We started out wanting to decrease heat absorbed into our cooling water system, and ended up with fuel savings and closer firing pressures between cylinders as an unintended benefit. Of course we had a coating much different that what you had, it covered the crown of a Cast Iron Piston (about the only thing at that time that would take the application process!), across the entire combustion chamber, including the valve head (faces), and the exhaust port including the elbow where it attached to the exhaust manifold log. To this day, I think that application in that manner is probably the only way to get "efficiency" payback off coating. Like dale mentions, coating the piston tops buys you time only. And even Swaintech will say that as well. Like anything else, it's insurance. Actually, it may have saved you from burning the pistons instead of just the "sponging" you got. It's too bad the coating place couldn't give you feedback on what their thoughts on it's degredation are... normally there is a glass-beading texture under the heat-barrier ceramics. Some of this new stuff is really amazing at what it can do. But like all the EFI ECU manufacturers say about a WBO2 being hooked up to their systems "O2 Correction does not substitute for a properly mapped system"---I think with that much detonation (even if inaudible) you may want to pull some timing, or richen it a bit. The Methanol should take care of it straightaway, and I figure you will be able to run more advance on-boost then. Dyno time will be the best $$$ you have spent. Doing tuning on the street is hit-and-miss at best on the high end of the map. What you might try to look for is a Dynapack Dyno for your mapping. These are the units that bolt to your axles. The first thing I noticed when using one of those the first time was how QUIET it was in the car! No wheel noise whatsoever. I know when JeffP was on the Mustang, we heard Detonation outside the car WELL before he ever heard it (if he heard it at all). And when he finally did "think" he heard it on his final pull, it was a full 700rpms after the dyno operator and I heard it clearly---I was in the panic "CUT CUT CUT!" mode giving signals like crazy to back off it was SO bad outside. That Dynapack is neat. You hear everything BUT wheels. Transmission bearings, Axle and Differential stuff...really neat to do at least once. Good Luck at the dyno! Quote Link to comment Share on other sites More sharing options...
Tony D Posted January 2, 2007 Share Posted January 2, 2007 I was gonna say maybe the electrode broke off somehow and caused all those dimples, but very very doubtful. I guess you burned up whatever caused it. I got three combustion chambers with "broken electrode" damage. Trust me, it doesn't look nice and symetrical and round like that! LOL Quote Link to comment Share on other sites More sharing options...
woldson Posted January 2, 2007 Share Posted January 2, 2007 i ll be posting my bros destroyed pistons but i want him to get a closer pic of what looks like round holes,,,,,he was a 10.5 to 11 to one compression running forged pistions and 12 psi, pistions melted in one or 2 good pulls on a street tuning! No coating. Quote Link to comment Share on other sites More sharing options...
OlderThanMe Posted January 2, 2007 Share Posted January 2, 2007 Well at 10.5:1 and 12 PSI I would expect the pistons to melt... that is a CR high enough for a hot N/A motor...much less adding boost. Even neutral pressure may be too much at that CR! Quote Link to comment Share on other sites More sharing options...
Workinprogress Posted January 2, 2007 Share Posted January 2, 2007 Did BRAAP weigh in on this yet? He may have some additional insite on what happened and how to prevent it again. Quote Link to comment Share on other sites More sharing options...
zguy36 Posted January 2, 2007 Share Posted January 2, 2007 To add to the list of unhappy cermaic coating users, I have had two engines that came apart looking just like 240hoke's, but without the FOD. One engine (l28et) had been run for 30,000 miles with roughly 75% of the coating flaked away. This engine had seen enough detonation to blow a copper head gasket with steel o-rings in the block, but there was no major damage to the stock pistons. In my opinion, if the coating can't even take the abuse that a stock piston can take, then it isn't doing much for you. The other engine was a mazda rotary that had 300 miles on it with a blown apex seal. Rotary's are very sensitive to detonation, and that is what caused the destruction of that engine, with only one instance of detonation due to fuel pump failure. In this case, large quantities of the cermaic coating had flaked away too, with only a handful of audible knocks. I can vouch for the application process of the coatings in both of these engines, since I am the one who coated them. www.techlinecoatings.com sells coatings to shops, but also for home use. Both engines were coated with the turbo specific application coating, with all instructions followed to the T. I don't know what you want to consider as anecdotal, but there seems to be a building case against these coatings. If the tests of seeing the coatings through from start to death is not scientific enough for you, I'm not sure what would be. The results that I have gathered, these coatings are worthless for the average user. The gain you get (lower oil temps, higher hp, lower coolant temps) are not enough to warrant the cost for a street application. The durability of these coatings is not enough to handle detonation of any sort. Quote Link to comment Share on other sites More sharing options...
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