NSFW Posted February 9, 2010 Share Posted February 9, 2010 True but I have seen factory cast pistons crack the ringlands with very little detonation where forged pistons can take smaller dets without any failure. How do you know they had seen very little detonation? Link to comment Share on other sites More sharing options...
timmafod Posted February 9, 2010 Share Posted February 9, 2010 You better pull those pistons and check them. Were you burning any oil? Pulling the pistons to check would be smart. I tend to not be smart however. I only had the car for 4k miles, right where I usually change my oil (I use royal purple, wix filters, and commute ~55 miles one way to work). I was at least a 1/2 quart low...when putting the oil in I was half way up the dip stick, at disassembly I wasn't on the stick at all, but there was a "decent" amount of oil in it. I never noticed any smoke at all ever out the tail pipe. The intake tract on the other hand was coated, there seemed to be puddles of oil everywhere inside there. I'll be installing two catch cans (one in crankcase PCV line, one in valvecover vent line) when it goes back in. I see there's clever ports for removing the wrist pins. How do you make sure the small end of the connecting rod aligns with the wrist pin hole in the piston when you reassemble? Oh, when it's out I'll also reinforce the oil pump pick up, I hear these crack. Link to comment Share on other sites More sharing options...
Boostin1657615274 Posted February 9, 2010 Author Share Posted February 9, 2010 (edited) The author repeatedly refers to "silicone" in the pistons. That instantly makes me doubt his credibility. (silicon is the proper term) Note he only refers to "all motor" in recomending cast pistons. 4032 is much stronger than cast, period. Detonation will kill any piston regardless of it's composition. I still feel the 4032 is a great choice for a DD. You can run OE clearance and get the long service life without beating the crap out of the cylinder walls. Just because Stephen Hawking can barely function doesn't make him any less of a genius. This guy made a 1-letter typo, and anyone reading the article knew what he meant. This is an article explaining the differences between a typical forged piston and cast, and makes people aware of the differences. I feel it is beneficial to note that 4032 pistons are more prone to causing ring lands, but 2618 pistons have sloppier tolerances and will wear down the block faster due to piston slap. I just wanted to point out the pros and cons of each. But keep in mind, this article was written for naturally-aspirated Honda all-motor builds, not turbo applications. It was a good resource to point out the facts. Edited February 9, 2010 by Boostin On the search for a new DD... Link to comment Share on other sites More sharing options...
GTTuner Posted February 9, 2010 Share Posted February 9, 2010 ^^^^^^^ I'm just nicken picken I guess. Although he does write silicone more than once. My spelling suks too. Link to comment Share on other sites More sharing options...
integroid Posted February 9, 2010 Share Posted February 9, 2010 How do you know they had seen very little detonation? The cast pistons were smooth on top and looked fine until you got to the ringland area. The forged pistons had what looked like marks that I assumed was caused by detonation. The ringlands on those were still intact and in perfect condition other than the marks on top. Link to comment Share on other sites More sharing options...
GTTuner Posted February 9, 2010 Share Posted February 9, 2010 True but I have seen factory cast pistons crack the ringlands with very little detonation where forged pistons can take smaller dets without any failure. No doubt......BUT, You can even break a 2618 piston if there is enough detonation. What about the Swain heat coatings, has anyone here tried that service? Link to comment Share on other sites More sharing options...
GTTuner Posted February 9, 2010 Share Posted February 9, 2010 I see there's clever ports for removing the wrist pins. How do you make sure the small end of the connecting rod aligns with the wrist pin hole in the piston when you reassemble? Remove the oil pan, pick-up tube and baffle plate and hold it up thru the crankcase. Link to comment Share on other sites More sharing options...
GTTuner Posted February 10, 2010 Share Posted February 10, 2010 There are two places you apply coatings on pistons: skirts and crown. Stock pistons have skirt coatings, and you want that on your forged pistons as well. Swain tech skirt coating is rumored to be very good and robust, better than "stock" coatings e.g. by CP. Crown coating should be used only in race applications. It keeps piston cooler, maybe "too cool" under regular low load driving. Even if it's not detrimental, it's really not needed. Thanks for clearing that up. I would never use a piston in a DD without the skirt coating, it works wonders. My 83,000 mile pistons hane no wear on the skirts at all. I was just wondering about that heat coat for the top, I agree it is probably overkill for a 300whp DD. What I did notice was the underside of my pistons have a brown "burn" spot right in the center, like oil was cooked a bit slinging off the small end of the rod. Thats why I was considering the top coating. Link to comment Share on other sites More sharing options...
integroid Posted February 10, 2010 Share Posted February 10, 2010 No doubt......BUT, You can even break a 2618 piston if there is enough detonation. What about the Swain heat coatings, has anyone here tried that service? I completely agree. My point was that the forged pistons can take more abuse than the stock cast pistons. I accidentally knocked off one of my EWG lines once and hit 30psi of boost. Got a cel with 3 cylinders with knock detected. Did a compression test and everything was fine. If that was the stock pistons, they would have been toast. Link to comment Share on other sites More sharing options...
GTTuner Posted February 10, 2010 Share Posted February 10, 2010 ^^^^^ My wastegate stuck during a dig with a turbocharged Acura RSX, saw about 25psi and hit fuel cut about 15 times. That is what broke my ringlands. :facepalm: Link to comment Share on other sites More sharing options...
Natejd04 Posted March 6, 2010 Share Posted March 6, 2010 I had a list of Mods installed onto my 05 LGT. I was a victim of the original VF39 going bad (bearing). So i decided to do upgrades on my car while it was down. I got a list of things added and done, than off to the dyno it went. A shop in my area while it was on the dyno made it through 3 pulls close to 300whp. However after the third they noticed a bad rattle in the engine and they went to expect it and now can no longer turn the engine over. They thought that it might be pistons, but its purely speculation. (lets get past the shop issue and the tune and focus on the pistons) Basically, is this the type of situation where I go back to OEM pistons and risk this same incident or Forged? It will be a daily driver, either way I want reliability. Just curious on opinion. Link to comment Share on other sites More sharing options...
NSFW Posted March 6, 2010 Share Posted March 6, 2010 Basically, is this the type of situation where I go back to OEM pistons and risk this same incident or Forged? I really doubt that the pistons have anything to do with your current problem, other than perhaps being collateral damage. Based on your wording ("go back to OEM pistons") I'm guessing that the motor was taken apart and reassembled. Since it only lasted for a few dyno pulls, I'm guessing that one or both of the following is true: a) A serious mistake was made when assembling the motor b) A serious mistake was made when tuning the motor Hopefully a teardown will indicate which. Regardless of the answer, I don't think I would make any component changes at this point, other than simply replacing the busted parts with new versions of the same parts. If you're lucky, the builder or tuner will accept responsibility. If you're not lucky, they'll point fingers at each other. In that case I'd take the motor to a shop like Maxwell (in Arlington) that can do the building and the tuning, so there will be no finger pointing if this happens again. Good luck... Link to comment Share on other sites More sharing options...
Natejd04 Posted March 7, 2010 Share Posted March 7, 2010 Okay I will find out on Monday after they dissemble to see what the real damage was. And Maxwell in Arlington ill check it out. Thanks, Link to comment Share on other sites More sharing options...
JSaladino Posted March 8, 2010 Share Posted March 8, 2010 damn i wish i had known quite a lot of this before my stockers went.... once you've had it rebuilt and you're having problems... it's quite a pain Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted March 22, 2010 Share Posted March 22, 2010 Great info in here. My '07 LGT with 50K miles just pushed a rod through the side of my block while I was leisurely cruising on the highway at 75MPH. I heard a pop, white smoke started pouring out and that was all she worte. I am debating on getting a stock EJ255 block or going with a EJ257 block with CP Forged Pistons, Forged Crankshaft and Forged Rods. Raw1Performance offers some reasobaly priced "street blocks", see bleow: http://www.raw1performance.com/index_files/Page523.html My current mod list is: Perrin TMICAEM CAIMaddad UEL Header/UP comboInvidia Catless DPPerrin CBECobb AP v2 Pro-tune298whp-325ft/lbs I was running moderate boost ~ 18.6psi on my summer map and ~15psi on my winter map. My winter map was loaded at the time my engine blew. Do you guys think it would be worth it for me to go with a "Stage 1" block with forged internals at my power levels as an "insurance policy"? Link to comment Share on other sites More sharing options...
Jdogg801 Posted March 22, 2010 Share Posted March 22, 2010 I am looking for a 2005 legacy gt factory (ej255) piston. Just one if possible... Does someone have one laying around maybe? Link to comment Share on other sites More sharing options...
LittleBlueGT Posted March 22, 2010 Share Posted March 22, 2010 Clark on NASIOC had a good post, can't find it right now, on the stock pistons. But basically our pistons are bigger then most, and that inherently leads to certain problems. FWIW engine builders have learned a thing or two in the past few years building suby motors. I believe the Cosworth pistons are becoming the piston of choice ($1000 or so) as they are forged have a very good rep, and have no audible piston slap at temps around -15F. A local had a SB with their pistons in it, and after me bugging him he did some cold starts in the winter w/o plugging it in. I agree that the tune is responsible for the vast majority of failures, but at some power level if one blows an engine, these might be the best option, and they seem to work just as well as OEM for a DD that puts many miles on. Full tune of 68HTA, KSTech 73 MAF, Racer X FMIC and ID1000s................by the DataLog Mafia!!! Link to comment Share on other sites More sharing options...
bosco Posted March 22, 2010 Share Posted March 22, 2010 This thread is worthy of being a "Stickey" Stay Stock Stay Happy Link to comment Share on other sites More sharing options...
Boostin1657615274 Posted March 22, 2010 Author Share Posted March 22, 2010 Great info in here. My '07 LGT with 50K miles just pushed a rod through the side of my block while I was leisurely cruising on the highway at 75MPH. I heard a pop, white smoke started pouring out and that was all she worte. I am debating on getting a stock EJ255 block or going with a EJ257 block with CP Forged Pistons, Forged Crankshaft and Forged Rods. Raw1Performance offers some reasobaly priced "street blocks", see bleow: http://www.raw1performance.com/index_files/Page523.html My current mod list is: Perrin TMICAEM CAIMaddad UEL Header/UP comboInvidia Catless DPPerrin CBECobb AP v2 Pro-tune298whp-325ft/lbs I was running moderate boost ~ 18.6psi on my summer map and ~15psi on my winter map. My winter map was loaded at the time my engine blew. Do you guys think it would be worth it for me to go with a "Stage 1" block with forged internals at my power levels as an "insurance policy"? Any time you are doing a motor build (any motor build really) you have to ask yourself a lot of questions first. 1. Will you be depending on this car--as in, when it runs will you need to keep it running? 2. Are you be making payments on this car? How much of a concern is depreciation and ease of resale? 3. How often do you think you will drive it? I think people have a lot of trouble estimating this. People who do hardcore builds end up wanting to drive the car more than they expected, and grow tired of certain parts they chose for the car. Other people think they'll love the thing and drive it all the time, but it just sits there because it's impractical or because they got bored with it for whatever reason. 4. How much power do you want to make? Now take the number you just came up with and add 10-25% to that value. That's how much power you will really want to make after the car has been running for a while. Trust me on this one. On the search for a new DD... Link to comment Share on other sites More sharing options...
bosco Posted March 22, 2010 Share Posted March 22, 2010 what are you willing to give up to get what you think you need? Stay Stock Stay Happy Stay Stock Stay Happy Link to comment Share on other sites More sharing options...
rao Posted March 22, 2010 Share Posted March 22, 2010 Nothing - forged pistons are better than stock POS pistons! That's what I've read Rob IF YOU CARE ABOUT YOUR CAR YOU SHOULD NEVER DRIVE IT Link to comment Share on other sites More sharing options...
bosco Posted March 22, 2010 Share Posted March 22, 2010 nothing - forged pistons are better than stock pos pistons! That's what i've read +1 Stay Stock Stay Happy Link to comment Share on other sites More sharing options...
JoeFromPA Posted March 23, 2010 Share Posted March 23, 2010 If stock are POS Rao, how come there are so many people running ~50% more power than stock for so many thousands of miles without problems? Huh? Why? Link to comment Share on other sites More sharing options...
Guest LGT-NY Posted March 23, 2010 Share Posted March 23, 2010 Nothing - forged pistons are better than stock POS pistons! That's what I've read Goddamn you with your sarcasm!!! I never know when you're being serious. Link to comment Share on other sites More sharing options...
Underdog Posted March 23, 2010 Share Posted March 23, 2010 I had the same trouble when I lost my cyl#4 ringland... very tough to separate the sarcasm (or humor, depending on how you are looking at it) from the good info. Your goals are not that far off from mine, power-wise. My engine rebuild thread may be relevant for you, since I hashed out the whole aftermarket/OEM piston thing too. The Crimson Dynamo Link to comment Share on other sites More sharing options...
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