Stock pistons are hypereutectic cast pistons, they are not bad all things considered.
Alloy is neither 4032 nor 2618, its something like 390.
Alloy is neither 4032 nor 2618, its something like 390.
I am considering the AMP44 pistons. They are 4032 but have massive width of material between ringlands which is the only weak point I can think of.
I had considered the Amp44 pistons before - they don't look bad, the 4032 is what I didn't like. I did notice they appear to use a different size ring pack than the Mahles or JEs. Mahle and JE use a 1mm top ring, this has a 1.55 top ring. Mahle and JE use a 2.8mm oil ring, this lists a 2.0mm oil ring. I don't recall what the OEM ring sizes are - I'll go measure in a bit, but I would think there is a benefit to Mahle and JE being aftermarket vendors with proper R&D groups, rather than the Chinese 'copy what we can' vendor.
I didn't know they had odd ring sizes. I just noticed they had a lot of metal between the rings. I emailed them with some questions and the shipping is about $180£ or $226.00 US. That is crazy.
Ouch - thats some high shipping when you consider how much those pistons cost. You can get some 4032 forged pistons on aliexpress for like $325 shipped.
No info on the ring sizes, but likely stock sized to re-use a common size. I doubt they are low tension 1mm rings. https://www.aliexpress.us/item/3256...56A_GSsVeJhoClPsQAvD_BwE&gatewayAdapt=glo2usa
No info on the ring sizes, but likely stock sized to re-use a common size. I doubt they are low tension 1mm rings. https://www.aliexpress.us/item/3256...56A_GSsVeJhoClPsQAvD_BwE&gatewayAdapt=glo2usa
I would go forged rod and stock piston with increased ring gaps. The typical issues I've seen posted over the years are ring land failures, likely due to rings butting so I'd oped up the gaps a bit and rods starting to noodle. Since you're not chasing big power or revving higher I don't see a benefit for going forged pistons.
Yeah, I am trying to go back better/stronger than stock but my usual thought of overbuilding something is diminished by the sky high price of some of the components. I am also still considering just going with Kingtec rods and pistons. I will employ a bigger ring gap no matter what I choose. I am also going to do the epoxy closed deck. It is going to cost me $150 (plus sugar) so that is an easy choice. One of my thoughts on replacing the original pistons is the fact that I assume that after many years and many heat cycles my original ones MUST be a little more brittle than new. My main thought is I am sure that SOME (definitely NOT all) of the Chinese options are just as good as name brands but if I choose poorly, tears will happen. Kingtec was my only consideration for Chinese pistons and rods since they just make sooo many and put their name on them. Zero to 60on YouTube had a review and said they sounded pretty competent in conversations. Another choice is AMP44 pistons. They are 4032 alloy but have a massive amount of metal between the top 2 ring gaps. That is definitely to beef up the known weak ring lands. They are not 2618, but with about double the metal between the lands that would be a massive strength advantage. The price of $500lb (~$626 USD) is pretty good BUT they charge $180lb (~$225 USD) to ship via FedEx making them actually cost ~$851.00. I am a 54yr old man and have money, but I also need to keep this (16yrs old +192k miles = not worth much) "fun" car within SOME reason. I still have some time to mull this over since I am slowly taking apart 2 engines to start picking the best pieces to rebuild into my "new" motor.
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I am thinking about 600-650hp. I already have upgraded to the HP28 transmission and have an LSD block kit in my large pumpkin 2007 rear end. So the motor is now the weak link.
