Is building a motor pointless?

[Austin@Wunderladen Racing]

I have asked the same question myself in this forum before with no luck.. Like OP, I was also wondering if building a forged motor with 4032 forged pistons that expand ~15% less than 2618 could lead to a daily driver bulletproof motor with much more miles to go before problems like oil consumption start. I have searched and it looks like at least one option by wossner exists so far...
https://pumaspeedpistonstore.com/products/wossner-honda-civic-1-5-16v-turbo-forged-piston-kit

4032 has a fairly high silicone content (which is why is has a lower thermal expansion). It's not as popular as 2618 because the silicone content makes it brittle and it has the same issue as hypereutectic pistons, it's not resilient to detonation. 2618 is much more elastic and is better able to absorb high pressure waves from detonation without cracking or failing. Most engine builders and machine shops that I've talked with about piston alloys don't recommend 4032 for high boost applications because unexpected detonation is much more likely to kill a piston than 2618.

I've spent a lot of time looking at the factory pistons and they're actually pretty solid as far as design goes. I've not seen any cases of L15Bs failing stock pistons or rings which is reassuring. My mindset right now is if you want over 380whp then you should get 2618 pistons. If you don't think you're going to want more than that then rods and head studs are really all that's needed. The caveat here is that nobody makes rods that work with the factory Si pistons. It's something I've looked into having made and it's certainly doable, but from a financial aspect I'm not in a position to pursue it right now (gotta make money before I can spend more money).

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[Spence]

4032 has a fairly high silicone content (which is why is has a lower thermal expansion). It's not as popular as 2618 because the silicone content makes it brittle and it has the same issue as hypereutectic pistons, it's not resilient to detonation. 2618 is much more elastic and is better able to absorb high pressure waves from detonation without cracking or failing. Most engine builders and machine shops that I've talked with about piston alloys don't recommend 4032 for high boost applications because unexpected detonation is much more likely to kill a piston than 2618.

I've spent a lot of time looking at the factory pistons and they're actually pretty solid as far as design goes. I've not seen any cases of L15Bs failing stock pistons or rings which is reassuring. My mindset right now is if you want over 380whp then you should get 2618 pistons. If you don't think you're going to want more than that then rods and head studs are really all that's needed. The caveat here is that nobody makes rods that work with the factory Si pistons. It's something I've looked into having made and it's certainly doable, but from a financial aspect I'm not in a position to pursue it right now (gotta make money before I can spend more money).

My other question, is on a scale of 1-10 how foolish would it be to do this? :

slam all fresh bearings with new forged pistons rods and pistons into my stock block once I have the transmission out.


I mean just due to the balances and such. I'm not super inclined to feel I need a tsp block, but it seems the tsp block is really a stock block with a cylinder support system kinda gurdle that goes in the cooling jackets.

I found out that piece can be had for $375 from cylinder support systems for the L15 B.


My plan was ppg gears and build the trans myself first, then pursue the rest when I'm financially able.

as you said and I've speculated nobody has cracked stock pistons, maperformance bent the rods and melted a hole through their cylinder wall with a multi hundred shot of nitrous and a big turbo.

Would be cool if you could just upgrade the rods lol.

 

[civic1989]

damn, 350whp in an si? that's gotta be a blast to drive!

 

[Spence]

damn, 350whp in an si? that's gotta be a blast to drive!

I bet it would be, and at that power level it would be reliable too once built the way I want. I mean in my opinion after 350whp meaning like 380 crank hp, in a front wheel drive car anymore than that is just worthless lol. I am determined to make it happen lol.

not that it matters but 350whp would troll pretty much anything on the street, not everything but would upset a v8 for sure

 

[Austin@Wunderladen Racing]

My other question, is on a scale of 1-10 how foolish would it be to do this? :

slam all fresh bearings with new forged pistons rods and pistons into my stock block once I have the transmission out.


I mean just due to the balances and such. I'm not super inclined to feel I need a tsp block, but it seems the tsp block is really a stock block with a cylinder support system kinda gurdle that goes in the cooling jackets.

I found out that piece can be had for $375 from cylinder support systems for the L15 B.


My plan was ppg gears and build the trans myself first, then pursue the rest when I'm financially able.

as you said and I've speculated nobody has cracked stock pistons, maperformance bent the rods and melted a hole through their cylinder wall with a multi hundred shot of nitrous and a big turbo.

Would be cool if you could just upgrade the rods lol.

I would not advise that for a few reasons.

1. When you change rods the bearing size you need will also likely change, Honda denotes this with different colors. If you don't have Vernier micrometers and are confident using them you are setting yourself up for an expensive failure.

2. All aftermarket rods require the block to be clearanced at the bottom of the cylinder for the wider beam.

3. Same goes for pistons, if you don't have a dial bore gauge and micrometers, just tossing pistons into a block is asking for trouble.


I do think a CSS is pretty overkill for sub 400whp goals, same goes for PPG gears. RV6 gears can easily hold the power you're looking for and are a fraction of the price.

I'm pretty confident as more people get invested in this platform the prices on stuff will start to come down. That's always how things go with modding cars as they get older.

 

[yaom1ng]

Exactly, the hpfp in the Si flows more than the one in the fk7, allowing you to get around 30 more whp than I can. The only options I have right now is to put an si intake cam in and run a honda accord hpfp (or an si one, but the accord one flows a bit more) and then I could probably get close to maxing out the 27won w2 at 375 whp. My intake cam wont work with the si or accord hpfp.

So if I don't want to swap out my intake cam, I need to wait until someone makes a higher flowing hpfp specifically for the base model 1.5 intake cam.

I'm custom dyno tuned from Derek at IMW.

I think the Si HPFP flows more than the FK7 because of the intake fuel lobe. @Precord96FK7 has run Skunk2 cams on Si and FK7 HPFP and has posted his findings.

 

[yaom1ng]

4032 has a fairly high silicone content (which is why is has a lower thermal expansion). It's not as popular as 2618 because the silicone content makes it brittle and it has the same issue as hypereutectic pistons, it's not resilient to detonation. 2618 is much more elastic and is better able to absorb high pressure waves from detonation without cracking or failing. Most engine builders and machine shops that I've talked with about piston alloys don't recommend 4032 for high boost applications because unexpected detonation is much more likely to kill a piston than 2618.

I've spent a lot of time looking at the factory pistons and they're actually pretty solid as far as design goes. I've not seen any cases of L15Bs failing stock pistons or rings which is reassuring. My mindset right now is if you want over 380whp then you should get 2618 pistons. If you don't think you're going to want more than that then rods and head studs are really all that's needed. The caveat here is that nobody makes rods that work with the factory Si pistons. It's something I've looked into having made and it's certainly doable, but from a financial aspect I'm not in a position to pursue it right now (gotta make money before I can spend more money).

 

[Austin@Wunderladen Racing]

I was able to find that video and he also shows the head gasket was compromised on 3 cylinders. The piston likely failed because the engine overheated and the ring ends butted. If the failure occurred from excessive cylinder pressure or detonation the failure would've occurred at the top land, not underneath the oil scraper. In his case the failed piston is an effect, not a cause.

 

[Berserk_FC3]

My other question, is on a scale of 1-10 how foolish would it be to do this? :

slam all fresh bearings with new forged pistons rods and pistons into my stock block once I have the transmission out.


I mean just due to the balances and such. I'm not super inclined to feel I need a tsp block, but it seems the tsp block is really a stock block with a cylinder support system kinda gurdle that goes in the cooling jackets.

I found out that piece can be had for $375 from cylinder support systems for the L15 B.


My plan was ppg gears and build the trans myself first, then pursue the rest when I'm financially able.

as you said and I've speculated nobody has cracked stock pistons, maperformance bent the rods and melted a hole through their cylinder wall with a multi hundred shot of nitrous and a big turbo.

Would be cool if you could just upgrade the rods lol.

pistons have been cracked/exploded

 

[Austin@Wunderladen Racing]

Do you have more details on this engine failure or how the car was modified? In many cases where rods fail they take the pistons out with them. Most piston failures I see are not the piston's fault.

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