Check out this Piston

[patmckinneyracing]

I need opinions on this. I know I'm going to ask my engine builder this week and my old man, but I want some outside opinions on this.

I got halfway through cleaning my pistons and found this one that has a small hole. It's not all the way through and only goes maybe a centimeter into the piston. It was completely filled by carbon, hence why I didn't see it until it was cleaned.

If you look in the pic, its the small spot in the bottom left valve relief. The other dark spot on the right side of the piston is simply part of the casting. I had some detonation issues 3-4 years ago, but never had valve to piston clearance issues or detonation since then. Any ideas? Can I still run this piston or is it not recommended? I'm running flat top, 4cc valve relief, hypereutectic pistons.

 

[HurstOlds]

I think technically you would be ok. That hole would just fill up again with carbon again. But if you're already inside the engine, I would just replace it with a new piston. I don't see doing all that work just to have something like that to worry about.

Pistons are cheap, if that burns through, that would be more expensive to fix

 

[JBreu]

Since you already have your motor apart you should just put new slugs in....You can get some forged keith Black ones for decent price......

 

[stomis]

Looks like a hot spot that burnt up from detonation that you managed to catch/remedy the detonation issue early...

The valve reliefs on those pistons are pretty fugly man. They should be shiny and smooth like the rest of the piston.


Check out the kit I'm going to use from summit on my 383 build. Scat cast steel crank, scat forged cap rods, and Forged aluminum +5cc flat tops with bearings and rings for $1000.

 

[SScamino]

Eagle has a kit that has a cast steal crank forged rods and Hyper pistons that come pre-balanced and also has the flywheel and balancer. It's a 383 kit and cost about 700 bucks. The balance is good on the parts it's what I used for my car. I also checked with my machine shop and they said they never have problem. The parts also come with the balance sheet that shows the weight of all the parts etc etc. I would just go ahead though and replace that piston its like 20 bucks.

 

[patmckinneyracing]

Stomis, these are hypereutectic pistons made by Speed Pro. Wouldn't they only be smooth if these were forged pistons?

 

[stomis]

Stomis, these are hypereutectic pistons made by Speed Pro. Wouldn't they only be smooth if these were forged pistons?

Look at the rest of the piston. Considerably smoother and better finish than the valve reliefs. While it may be true that the forged pistons will come shiny because theyre cut there is no reason the hyper pistons cant be finished good like that.

 

[stomis]

Eagle has a kit that has a cast steal crank forged rods and Hyper pistons that come pre-balanced and also has the flywheel and balancer. It's a 383 kit and cost about 700 bucks. The balance is good on the parts it's what I used for my car. I also checked with my machine shop and they said they never have problem. The parts also come with the balance sheet that shows the weight of all the parts etc etc. I would just go ahead though and replace that piston its like 20 bucks.

I'll pass on eagle stuff...

 

[patmckinneyracing]

Which brand is better: scat or eagle? I've heard of quality issues popping up with both of these brands

 

[chevy2480]

I ran the eagle 383 kit and went 11.90 on it but had crank key way issues twice destroyed two cranks and a buddy of mind has also had crank failures where balancers started to wobble with bolt very tight dont know why maybe snout is a liitle small. So that being said i would lean towards scat.