pedrosixfour Posted October 24, 2015 Share Posted October 24, 2015 So is it cast or forged ? It seems you must take the answer to that question into exile with you mate. The suits will be along to move you to a "safe" location shortly. Bye Dunk! Quote Link to comment Share on other sites More sharing options...
Dnk Posted October 24, 2015 Share Posted October 24, 2015 Still here Quote Link to comment Share on other sites More sharing options...
V8KILR Posted October 24, 2015 Share Posted October 24, 2015 All the knowledgeable sources I have read say this: Forged crank & rods. Pistons are high silicon cast (hypereutectic). Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted October 24, 2015 Share Posted October 24, 2015 I believe they are cast steel. Quote Link to comment Share on other sites More sharing options...
Dnk Posted October 25, 2015 Share Posted October 25, 2015 Wouldn't a close look at a stock crank show whether it's cast or forged due to casting flash lines being different to forging lines ? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted October 25, 2015 Share Posted October 25, 2015 (edited) This seems a US led idea, based on GM cranks, I don't think it's reliable on *ALL* cranks. I go by the colour of the sparks when a crank is ground, and how it "rings" if suspended and tapped. Cast steel alloys are nearly as strong as forgings or billet cranks these days, such has the casting and heat treat process come on. There won't be many engines in modern cars using the old style grey cast iron cranks, I would think. Someone could write to Toyota, and ask, I guess they'd like something to read apart from "My X has just set on fire via the crap in my window winder switch" Or "Have you fixed the emission test results like VAG?" Edited October 25, 2015 by Chris Wilson (see edit history) Quote Link to comment Share on other sites More sharing options...
Digsy Posted October 25, 2015 Share Posted October 25, 2015 This seems a US led idea, based on GM cranks, I don't think it's reliable on *ALL* cranks. I go by the colour of the sparks when a crank is ground, and how it "rings" if suspended and tapped. Cast steel alloys are nearly as strong as forgings or billet cranks these days, such has the casting and heat treat process come on. There won't be many engines in modern cars using the old style grey cast iron cranks, I would think. Someone could write to Toyota, and ask, I guess they'd like something to read apart from "My X has just set on fire via the crap in my window winder switch" Or "Have you fixed the emission test results like VAG?" I'd be very surprised it it was cast steel. I believe steel castings are quite expensive, and are more the domain of high performance turbine housings, exhaust manifolds and direct injection fuel rails. Plus you wouldn't get the so-called "fibre" flow in a steel casting. I just checked a couple of recent papers and as you say grey cast iron cranks are being pushed out by forged steel as the downsizing trend continues, cylinder pressures go up and bearing sizes come down in an effort to reduce friction. Even GM's new SGE 3-pot cooking engine has a forged steel crank. The 2JZ crank seems pretty well proportioned and I'm guessing that since it was designed back in the early 90's, cylinder pressures wouldn't have been that high. But given the amount of abuse it seems to be able to take, and the fact that its a long twisty I6 probably means it is a forged crank. Quote Link to comment Share on other sites More sharing options...
Alex Posted October 26, 2015 Share Posted October 26, 2015 Digsy...that SAE paper you found me - will it be in there? This second I'm not sure if it's with me here or in the storage unit. Quote Link to comment Share on other sites More sharing options...
adnanshah247 Posted October 26, 2015 Share Posted October 26, 2015 maybe i'll get properly slated for this but I believe its forged and ill explain why. Ever since I joined the forum and car heavy modification scene every time I hear the word 'strokered' its always assigned to forged parts. Any engine you hear about that has been strokered has always got forged pistons etc. etc. etc. on any forum, any car show etc. Seen as the 2JZ is a strokered version of the 1JZ isnt it fair to assume that the crank would be forged??? I maybe well out of my knowledge here but its a thought that just occurred to me..... Quote Link to comment Share on other sites More sharing options...
Gaz6002 Posted October 26, 2015 Share Posted October 26, 2015 'Stroked'... stroking an engine is just a way of increasing displacement by using different-sized internal components. It doesn't assume any particular material, though I'd start with a metal rather than, say, cardboard. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted October 26, 2015 Share Posted October 26, 2015 Given the difference in stroke I would expect they would use different forgings for each engine, assuming they are actually forged.... The shorter stroke crank would show where excess material was machined away had it come from a forging that would also give the long stroke 2JZ cranks. Quote Link to comment Share on other sites More sharing options...
adnanshah247 Posted October 26, 2015 Share Posted October 26, 2015 Given the difference in stroke I would expect they would use different forgings for each engine, assuming they are actually forged.... The shorter stroke crank would show where excess material was machined away had it come from a forging that would also give the long stroke 2JZ cranks. right, i think im partially with you, you wouldnt mind explaining in more detail would you chris....i learn a shed load from all your posts! Quote Link to comment Share on other sites More sharing options...
j_jza80 Posted October 26, 2015 Share Posted October 26, 2015 (edited) When someone refers to a 'stroker engine', they refer to one that has an aftermarket crankshaft and conrods, to increase displacement (cylinder capacity). The high end stroker kits, from the likes of JUN, Cosworth, OS Giken, HKS, Crower etc tend to be forged components. This has no bearing on the material of the original crankshaft. As for the 13 year old original question, the concensus is that the cranks are forged. But whatever materials the stock internals are made from, they were definitely done right first time. Edited October 26, 2015 by j_jza80 (see edit history) Quote Link to comment Share on other sites More sharing options...
Digsy Posted October 26, 2015 Share Posted October 26, 2015 Digsy...that SAE paper you found me - will it be in there? This second I'm not sure if it's with me here or in the storage unit. No, I already checked that. It re-iterates that the rods are forged but doesn't mention the crankshaft material. Quote Link to comment Share on other sites More sharing options...
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