Compression opinions?
What are "the best" pistons on the market for these cars for anything other than power? I have reasonable goals of 500-600whp which realistically any piston can handle, just not sure given the amount of options so more aiming towards consistency/quality/easiest to build, quietness, least oil consumption, etc (pretty much anything other than power I guess). All below are 2618 forging. Does not help my machinist has no preference lol. He's used everything apparently.
Do the piston weights matter?
Wiseco 1400HDs K626M86AP? 349g avg weight, cheapest/most common, proven option I guess.
https://www.extremepsi.com/store/Wis...II-and-IX.html
JE FSRs? 309g avg weight, cheapest. There's also JE Ultras but they're 10.0:1 comp and probably not off the shelf.
https://www.extremepsi.com/store/JE-...II-and-IX.html
Diamond 82005-4? 356g avg weight and has gas ports, moly coated skirts, and "forced pin oilers from the oil ring". 3-4 week order time (all custom not off the shelf). Had these in my motor and were okay.
https://www.realstreetperformance.co...-3cc-9-11.html
Manley Extreme (345g) or Turbo Tuff (375g) Pistons? Thickest wrist pins on the Turbo Tuffs @ .250in but also heaviest. Has gas ports on the Turbo Tuffs, all off the shelf (TurboTuff might be harder to get).
https://www.realstreetperformance.co...06310ce-4.html
https://www.realstreetperformance.co...-stroke-2.html
Do the piston weights matter?
Wiseco 1400HDs K626M86AP? 349g avg weight, cheapest/most common, proven option I guess.
https://www.extremepsi.com/store/Wis...II-and-IX.html
JE FSRs? 309g avg weight, cheapest. There's also JE Ultras but they're 10.0:1 comp and probably not off the shelf.
https://www.extremepsi.com/store/JE-...II-and-IX.html
Diamond 82005-4? 356g avg weight and has gas ports, moly coated skirts, and "forced pin oilers from the oil ring". 3-4 week order time (all custom not off the shelf). Had these in my motor and were okay.
https://www.realstreetperformance.co...-3cc-9-11.html
Manley Extreme (345g) or Turbo Tuff (375g) Pistons? Thickest wrist pins on the Turbo Tuffs @ .250in but also heaviest. Has gas ports on the Turbo Tuffs, all off the shelf (TurboTuff might be harder to get).
https://www.realstreetperformance.co...06310ce-4.html
https://www.realstreetperformance.co...-stroke-2.html
I'd be more concerned about saving Rod weight and would go into a Carrillo rod for its weight and strength. Less weight is easier on the bearings.
I'm running a custom CP/carrillo package in both cars and it works well.
Last edited by Abacus; Aug 19, 2020 at 10:00 AM.
I'm reusing my Manley Turbo Tuff 150mm I beams w/ARP 625+ Rod Bolts and 88mm Crank. The Carillo Rods at 567g (vs 675g of the Turbo Tuffs) would be tempting if my rods were done but I'm 99% sure they're serviceable as the car didn't spin a rod bearing.
Wisecos, JE FSRs and Manleys don't have gas ports, only the Manley Turbo Tuff Pistons and Diamonds have gas ports but both look like custom order affairs (plus the Turbo Tuff Pistons are the heaviest piston...roughly 25g heavier than the Diamonds I had in my old motor). The CPs have a .180 pin which seems a bit weak, don't think the JE is worth considering for the .150 pin too.
Have a feeling it'll come down to the Wisecos or Manley Extremes, I'll ask my machinist. A lot of his builds use Wisecos but he has experience w/everything.
Wisecos, JE FSRs and Manleys don't have gas ports, only the Manley Turbo Tuff Pistons and Diamonds have gas ports but both look like custom order affairs (plus the Turbo Tuff Pistons are the heaviest piston...roughly 25g heavier than the Diamonds I had in my old motor). The CPs have a .180 pin which seems a bit weak, don't think the JE is worth considering for the .150 pin too.
Have a feeling it'll come down to the Wisecos or Manley Extremes, I'll ask my machinist. A lot of his builds use Wisecos but he has experience w/everything.
That shouldn't matter if its old or new hell I've seen tons of old **** put on e85 with a way to tune it and made good power. My gf stepfather has a 71 charger and challenger both with original engines one is fuel injected and the other he just bought but the challenger has fuel injection on the original engine and it makes 700 wheel all day long with its mods and e85. So I don't buy that one bit.
That shouldn't matter if its old or new hell I've seen tons of old **** put on e85 with a way to tune it and made good power. My gf stepfather has a 71 charger and challenger both with original engines one is fuel injected and the other he just bought but the challenger has fuel injection on the original engine and it makes 700 wheel all day long with its mods and e85. So I don't buy that one bit.
That shouldn't matter if its old or new hell I've seen tons of old **** put on e85 with a way to tune it and made good power. My gf stepfather has a 71 charger and challenger both with original engines one is fuel injected and the other he just bought but the challenger has fuel injection on the original engine and it makes 700 wheel all day long with its mods and e85. So I don't buy that one bit.
Ask yourself this question.
If more compression was the answer don’t you think more people would run it on these cars.
Keeping the headgasket ,rod bearings and valves intact would be a challenge .
May want to do some research on compression and tuning . Every fuel, engine and setup has its limits.
Ask yourself this question.
If more compression was the answer don’t you think more people would run it on these cars.
Keeping the headgasket ,rod bearings and valves intact would be a challenge .
Ask yourself this question.
If more compression was the answer don’t you think more people would run it on these cars.
Keeping the headgasket ,rod bearings and valves intact would be a challenge .
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Well an engine with that much compression usually requires some domed pistons (AFAIK). With that kind of setup piston to valve clearance is pretty critical, so if I was you I would probably do a compression and leak down test to make sure its still sealing up ok.
No, as in an Evo is going to run like trash at 12.5:1 compression on pump gas, even without boost. We don't have the cylinder head to get away with that. Your gf's friend's stepfather's uncle isn't running 12.5:1 on his Mopars on pump gas either. At 10.5:1 with a tune to limp on low ethanol, maybe, but it's not going to be pleasant. I'd much rather sacrifice that last bit of power from compression to be able to run a mean tune on pump gas and not have to worry about it blowing up.
I did compression test last week being i washed the cylinders and i was still in the 200s after wetting the cylinders after changing the oil.