Started shopping for pistons for my fwd KA24E buildup, and looking for as much input as possible. Who is running what brand, what rings and how much boost? What compression ratio? What is your cold start noise like with the pistons you are running?
Currently considering CP, Ross and Arias, leaning toward Ross because of price, however i want a high silicon content piston to eliminate cold start noise which i believe Ross don't offer.
What i'll be running engine wise:- Garrett T3/T4, 60-1 comp cover, 0.63 AR internally gated turbine housing, stage 3 turbine, journal bearing, water cooled; max boost roughly 20psi, low around 7psi- Stock prep'd cryo treated rods and crank- OEM nissan bearings- OEM headgasket/bolts- Solid lifters w/custom billet mechanical grind cam- Additional fuel/ignition control by an SMT6 piggyback ECU, running 4 extra 550cc/min injectors, boost dependant ignition retard
Forged pistons: who is running what?
I'm running the ross's, cant comment on cold start except for the two cylinders of my engine that are running didn't rattle when I fired it up 
However, I dont know anybody that haves issues with cold start on them. Also, my machine shop considered it a non-issue considering the relatively small bore of KA motors. My ross's sure were pretty, I'd put my money on them Both of your other choices are high on my list as well though, I dont think you'd be disappointed any way you went. Also, if I remember correctly, the low silicone 2610 alloy you spoke of is stronger than the high silicone 5somethin alloys the others use. (I just woke up, can anyone tell?)
However, I dont know anybody that haves issues with cold start on them. Also, my machine shop considered it a non-issue considering the relatively small bore of KA motors. My ross's sure were pretty, I'd put my money on them Both of your other choices are high on my list as well though, I dont think you'd be disappointed any way you went. Also, if I remember correctly, the low silicone 2610 alloy you spoke of is stronger than the high silicone 5somethin alloys the others use. (I just woke up, can anyone tell?)Thanks Nathan, the high silicon content doesn't allow the piston to expand as much as it would if it was a low silicon piston, helping eliminate piston slap when cold. I guess it's not really an issue....Just waiting on mike from ka24de.com to get back to me on some flat top ross's for the E so i don't end up with 7.5:1 CR.
Yeah, I know it does What I mean is that the diameter of the bore is rather small, the skirts are rather long, and for some strange reason I've never heard of a KA with ross's experiencing piston slap. I dunno why, but they just haven't...and my two cylinder lawnmower KA doesn't seem to either and its been cold for 11 months!
What I mean is that the diameter of the bore is rather small, the skirts are rather long, and for some strange reason I've never heard of a KA with ross's experiencing piston slap. I dunno why, but they just haven't...and my two cylinder lawnmower KA doesn't seem to either and its been cold for 11 months!-
Structure240sx
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It'd be really interesting to know what piston to wall clearances everyone with the ross pistons are running also 
I think the machine shop said they set it at .005 inches for mine. I kinda expected a bit of cold start slap but perhaps I'll get away without any or it'll be minimal like hugue's. I remember a post by adamhu talking about his ross's and the fact that after the rebuild he could actually rock the pistons in the bore a little by hand but once he got it running there was no slap. I thought it was interesting, his is an E also
I think the machine shop said they set it at .005 inches for mine. I kinda expected a bit of cold start slap but perhaps I'll get away without any or it'll be minimal like hugue's. I remember a post by adamhu talking about his ross's and the fact that after the rebuild he could actually rock the pistons in the bore a little by hand but once he got it running there was no slap. I thought it was interesting, his is an E also