4032 Alloy Pistons for 500whp?

I realize that Mahle and SP63 make 4032 alloy pistons for us (probably others do too). SP63 metions that they're okay up to 425whp:
http://www.speedperf6rmanc3.com/categories/built-engines/mazda-mzr-disi/long-blocks.html

The pistons in question:
http://www.speedperf6rmanc3.com/products/sp63-4032-series-pistons-for-mazda-mzr-disi.html

Anyone have experience running these? To me, it seems like 425whp is very little increase in power headroom over stock pistons. Folks have run stock pistons with enlarged ring end gaps to address ring butting/ringland cracking issues with some success. So shouldn't these 4032s be able to handle more power with different PWC and ring-end gaps?

I'm curious about this because 4032s seem to be the "just right" mixture of increased durability over stock, yet offer a longer service life and less likelihood of piston slap than 2618s. Those of us who DD our Speeds may like a compromise, which I believe is the reason 4032s are offered. But is a reliable 500whp possible on these with differences in assembly spec choices, or am I just chasing a pipe dream? A reliable 500whp DD with the appropriate extra fueling (methanol or PI), clutch selection, and turbo choice (like an EFR7163) would be a blast to drive for a long time if the pistons could go more than 30-40k miles before causing bore ovaling or other issues.

 

I have never really heard many concerns of doing 500 HP on anything but the stock ones. I think some things on their site are labeled to sell if you know what I mean, Like if you read the differences in the stages of blocks, I think the requirements and capabilities are inflated a bit. When I read their site i feel like if I don't have stage 3 build with sleeves ill blow it up.

I would not do you research based on their site is my implication and you should call one of the piston manufacturers and ask them directly instead of basing your decision on a shop that wants you to buy the more expensive component. I like the company, not saying anything bad, they are not doing anything wrong, but ..... Do you specific research on this elsewhere, then after you chose - > Buy from SP63 if you want.

 

That's good advice. By doing that, the piston company rep doesn't have a "dog in the race" sales-wise.

My goal would be to have a very DD reliable/livable 500whp capable motor that'd be just as comfortable making a grocery store run as doing repetitious laps on a road course, being driven at 10/10ths. I wouldn't want to have to rebuild after only like 50k miles either. I'd keep my balance shafts and also want a keyed crank/pinned cams from the perspective that "an ounce of prevention is worth a pound of cure."

 

From what I've read you should definitely be good to 500 with the 4032 pistons. That material is just less pliable and therefore more sensitive to detonation than 2618 pistons.

That being said though, is piston slap is your concern, I have read no threads where people reported slap from SP63's 2618 Pro Series pistons. They're actually the ones I decided to go with for my build where my goal is [hopefully] somewhat north of 600whp. In my research, I didn't see enough benefits with the 4032 material to justify them as my Speed isn't my daily.

 

FWIH, piston slap is just one aspect of service life; 4032s are supposed to reliably last longer, but I could be wrong. And I'd have a lot of alcohol flowing through the engine anyways (E25 + ~CM14 or so spraying 100% methanol), so hopefully that'd keep things really cool and prevent issues like we have with stock pistons' ringlands. And with that much alcohol-based fuel, I should have zero issues with detonation or uncontrolled flamefront.
[doublepost=1469558034][/doublepost]Further info, straight from SP63:
"Yes with the new coating we have it will be able to reach 500whp."
I assume they're referring to the hard anodizing:

 

Keeping the balance shaft on a built block is going to be a royal pain in the ass. I suggest you look at the shop manual to see what you are in for.

 

I dont see mention of keeping a BS in this thread, but I would not do it if it were me.

 

Try reading better

Bolding mine

 

@nindoja I recall you mentioning keeping your BS/you knew people who kept it in their built motor. Any comments as to pros/cons?

 

Indeed. That's why I'd have a pro who's built Mazdaspeed engines do it. I'm fully mounted already, so I know the vibes would be really bad. And the build concept wouldn't be about having 700 whp, creating a 1/4-mile beast, becuz racecar, etc. Having no balance shafts (and the consequences thereof) doesn't fit into the concept of what I'd be going for.

More good news from SP63 regarding service life:
"Yea there are a lot of variables to how long a piston can last. I can not give a time frame on how long 4032s will last but they are known to last significantly longer than the 2618s."

This is really awesome because it fits squarely into my goals for the build.

 

What's your rationale for that? Sure it's heavy, but most of that weight isn't sprung weight on the crank.

I don't have my balance shaft and the vibes/noise are terrible. @JgamB kept his balance shaft and is right at (over?) 500whp and beats on his car daily. No issues to report with his engine and he's put a few thousand miles on it already. And he didn't really do a break-in because he has no patience for not boosting.

If you're building an engine already, I can't see retaining the balance shaft being that much more work. Sure, you get to possibly buy some shims from Mazda, but the process isn't that hard. Just make sure you time it in the proper orientation (per the manual).

@Redline I've been talking to @fjperformanceinc about keeping balance shafts. They'd probably do it for you if you asked. And conveniently, they are offering $1k off their builds through the end of August.

 

TL;DR fully mounted/aftermarket suspension is enough NVH for me; no way I'm going BS-less on top of it.

Yeah, BS intact is a no-brainer for my overall goals/vision for the build. They cancel out the secondary imbalance forces intrinsic to I-4 engines. I'm not afraid the engine is going to fall apart without a BS - I know that's not the case. But if I can have DD smoothness by keeping the BS intact, I'm all for it. That's what I'll be doing, if/when I build. I've already expressed elsewhere that my NVH tolerance is on the low end of the scale, and I see no reason to guarantee I'll have a ton of extra NVH by doing away with the BS assembly, especially being fully mounted (and completely unwilling to change that too).

If I want to make the engine more rev-happy, I can look into lighter flywheels, maybe even aluminum ones, to increase responsiveness. But BS delete isn't on the table.

As a big fan of engineering, in general, and its practical applications in the automotive world, I'm unfortunately relegated to being a dilettante. I chose a different career path through my undergrad and graduate work. Regardless, I found this particular video from an actual engineer helped me to develop a much deeper understanding of the primary and secondary forces seen in I-4 engines. He's a great guy to sub to as well, and talks a lot about the "black art" of suspension too, @VTMongoose , @ConeKiller , @phate, and @Nliiitend1 . But most of it is stuff you probably already know:



And bringing it all together:

 

I can read you talking about it just fine, but noone else mentioned it first so It seemed like you were responding to a previous comment, but I could not find any other comments.
[doublepost=1469709562][/doublepost]

My reasoning is only that a long time ago there was speculation of the BS causing issues (never proved) everyone afraid of ZZB, but the real reason is it has been tried and true without it. I raise my idle up to 1k and its not a problem fully mounted, now at stock idle its a nightmare but a simple RPM adjustment is all it takes to overcome.

So, without many built cars having it and them surviving just fine is my rationale. If you want to be the first people to test it then go right ahead and prove its fine and I might put one on my next build. Its just something that is not done frequently in builds. I know you said one guy is at 500 hp using one, that is fine, but this is the first I have heard of it.

 

I'll probably use the SP63 4032's and keep the balance shafts in my build, whenever that happens. Definitely not this year.

In my mind if the SP63 4032's can legitimately handle 425 whp in a track situation, that's a huge upgrade over stock, which can't handle anywhere near that. I think they will be the best choice for me given the mileage I put on the car and the fact that it's my daily.

 

Yeah, and they're saying 500 now, with the new coating they use, but I'm not sure if that'd be in a track situation/constant 10/10ths driving. I'd think so.
[doublepost=1469724350][/doublepost]@VTMongoose (and others, for that matter), here's some good info from SP63. The more and more I learn, the more I'm thinking 4032s would be perfect for me:

Yea there are a lot of variables to how long a piston can last. I can not give a time frame on how long 4032s will last but they are known to last significantly longer than the 2618s (SP63)

Thanks so much. That’s great info! I think I’ll probably choose the 4032s when the time comes.
Just curious: when you say 500whp would be fine with them, given their coating, do you mean for tracking events where it’s running at high horsepower for long periods of time? Or would 500whp only be reliable for occasional wide-open throttle pulls? (trying to understand to make the best choice – I’ll be tracking…) (me)

What kind of tracking will you be doing? It will be fine im just curious. Of course they wont last as long as someone else running their motor just a few pulls here and there but that is to be expected

Most likely auto-x and road courses. In light of that (longer high-rpm/high-load operation), maybe opening up the ring-end gaps a little would be a good longevity measure?

For that application you will be fine. Even though its high rpms for an extended amount of time its not a high amount of power.

 

I would factor climate into your choice also. If you live up North / colder area, your car is going to take longer to get up to operating temp, and that is where the 2618s are a liability for beating up the cylinder walls. I looked at 4032s also, but had a sneaking suspicion they might still be ring land liabilities. I guess we'll find out.

And yes, keep your balance shafts. The two tits on the two drums face down, toward the oil pan with cyl1 at TDC on the compression stroke. Other than my recently made loud again exhaust, my car is very civil and fully DM mounted. @nindoja knows I change my exhaust about as often as socks haha.

 

Climate or no, the service life being much longer and capability to handle 500whp seals it for me. Thanks for the info about the BS orientation, but I'm not about to DIY the first time on a new, expensive engine, LOL. I'll get a well-qualified pro.

 

You also have different power goals and requirements than us.

 

[doublepost=1469757573][/doublepost]

I see you're spraying 20gph, @JgamB . What turbo/power levels? I figure, based on what SP63 said, that these pistons can easily live a long life at 500whp, even when using the car for tracking. But with you flowing that much methanol, I suspect you're 550+whp?

 

It's about at that level most likely - 95% IDCs with the meth flowing and massively descaled MAF curve. We'll see. The target audience for 4032's is someone like @VTMongoose that packs on the miles, hits the occasional AutoX, road course, etc. I flog my car daily (once she's up to temp, never before).