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Piston damage analysis

Shame on me for thinking I had an original idea, punched in "electronic det cans" in google and sure enough, tuns out it has been done already. I don't know Harald, is he a user on the forum?
 
timing was a little high compared to what I normally see, but perhaps not out of question. are the rods bent? 7.8 :1 is borderline anemic.
 
Thanks on the timing feedback, I'll keep that in mind.

The compression ratio is theoretical, not measured. I still need to assemble the whole thing. I think this is the piston kit. As you can see, advertised as 8.0:1 compression. Don't know where my guy came up with 1:7.8, probably calculated, but that's near enough to call the same. Good for running a lot of boost.
 
If by "a lot of boost" you mean, constantly over 30psi, sure maybe.

Nice pistons, I'd run a thinner hg and maybe skim off the head a little bit. Verify rod straightness of the rods. I'd personally just get a set of hbeams regardless and move on, but ymmv. These days, 9:1 is low compression, anything much lower than that is either very high output or just old.
 
I wouldn't build that type of an engine under 8.5:1 compression ratio. 9:1 would still be ok. The lower it is you lose in driveability, fuel economy and the engine wakes up later. It's all about the tune.
 
Went and picked up the engine block today, all nicely cleaned, bored and honed and he surprised me with the pistons, turned out he was able to source a Wiseco FORGED piston kit for the same price as original pistons, nice, brought a smile to my face. Need to do a couple things to the block, like deleting the stupid pcv, and then it's time for reassembly.

Nice! Now you need a set of HBeam rods!
 
If by "a lot of boost" you mean, constantly over 30psi, sure maybe.

Nice pistons, I'd run a thinner hg and maybe skim off the head a little bit. Verify rod straightness of the rods. I'd personally just get a set of hbeams regardless and move on, but ymmv. These days, 9:1 is low compression, anything much lower than that is either very high output or just old.

Well, I do have a Holset HX35 sitting on the shelf, waiting to go in:). I'm looking for h beam rods but it doesn't look promising. I actually drove my block to and from the shop in a WRX with (stock) 8:1 compression, that thing flies, even in low rpm it's pretty good. Would it really be so much different in a b230?

I wouldn't build that type of an engine under 8.5:1 compression ratio. 9:1 would still be ok. The lower it is you lose in driveability, fuel economy and the engine wakes up later. It's all about the tune.

My engine was 8.7:1 stock.

Nice! Now you need a set of HBeam rods!

I know right! I'm trying to source them in a timely manner but it doesn't look promising. I think I might just put it together as is and check out the effect of the compression change. If I don't like it I'll have the shop machine the head a little bit and throw in H beams at the same time.
 
I wouldn't build that type of an engine under 8.5:1 compression ratio. 9:1 would still be ok. The lower it is you lose in driveability, fuel economy and the engine wakes up later. It's all about the tune.
Mine is 8.5-1 I don't suffer any of those characteristics. Have you driven an 8.5-1 car to know what your talking about or just repeating what you've read on the all knowing internets?
 
there's definitely a difference, it's not bench racing.

but you guys can go ahead and ignore 17 years of experience dealing with all types of volvo engines and do your own thing. I don't have to drive it or deal with it, not my problem if your stuff doesn't quite measure up ;)

I'm not sure I would use a subaru engine as a good example, they seem to lose pistons regardless of what the static CR is on otherwise stock turbo engines.

Rods can be bought off ebay, from vendors nearby (I'm sure you could get a set from sweden pretty quickly), etc. Might do yourself a favor at the same time and get the ones that convert to crank-steered vs the OE piston steering that goes on in b230s. No machining necessary.
 
there's definitely a difference, it's not bench racing.

but you guys can go ahead and ignore 17 years of experience dealing with all types of volvo engines and do your own thing. I don't have to drive it or deal with it, not my problem if your stuff doesn't quite measure up ;)

I'm not sure I would use a subaru engine as a good example, they seem to lose pistons regardless of what the static CR is on otherwise stock turbo engines.

Rods can be bought off ebay, from vendors nearby (I'm sure you could get a set from sweden pretty quickly), etc. Might do yourself a favor at the same time and get the ones that convert to crank-steered vs the OE piston steering that goes on in b230s. No machining necessary.

I don't think I'm ignoring you, I very much appreciate you sharing your experience. That said, I think experiencing something yourself is very valuable and something you can take with you for life. So I think I'm going to try it and if I don't like it rip the head of and have it machined. Taking the head off is easy.

Good news, I think I found a UK supplier: https://www.maxspeedingrods.co.uk/high-performance-volvo-b230-h-beam-connecting-rods-conrods.html. Will those bolt up, nothing else needed? Are these the ones that are crank steered?
 
I don't think I'm ignoring you, I very much appreciate you sharing your experience. That said, I think experiencing something yourself is very valuable and something you can take with you for life. So I think I'm going to try it and if I don't like it rip the head of and have it machined. Taking the head off is easy.

Good news, I think I found a UK supplier: https://www.maxspeedingrods.co.uk/high-performance-volvo-b230-h-beam-connecting-rods-conrods.html. Will those bolt up, nothing else needed? Are these the ones that are crank steered?

You can write and ask questions about the rods directly to Maxspeedingrods. They responded pretty fast the last time I asked them a question regarding their Volvo Whiteblock rods.
 
I don't think I'm ignoring you, I very much appreciate you sharing your experience. That said, I think experiencing something yourself is very valuable and something you can take with you for life. So I think I'm going to try it and if I don't like it rip the head of and have it machined. Taking the head off is easy.

Good news, I think I found a UK supplier: https://www.maxspeedingrods.co.uk/high-performance-volvo-b230-h-beam-connecting-rods-conrods.html. Will those bolt up, nothing else needed? Are these the ones that are crank steered?

It was not a response directed solely at you.

lemme go look, 24.8mm is something of a grey area in the memory bank. the length is correct. I'll go check in the archives and get back.
 
based on some old spreadsheets I've got from the good oriental folks, 24.8 to 25.2 is what you'd be looking for for crank steerage.
 
You can write and ask questions about the rods directly to Maxspeedingrods. They responded pretty fast the last time I asked them a question regarding their Volvo Whiteblock rods.

Email sent, thx.

based on some old spreadsheets I've got from the good oriental folks, 24.8 to 25.2 is what you'd be looking for for crank steerage.

Thanks, nice. Does that mean I don't install the little end spacers that came with the Wiseco piston kit? The ones that go in between the rod and the piston.
 
Email sent, thx.
Thanks, nice. Does that mean I don't install the little end spacers that came with the Wiseco piston kit? The ones that go in between the rod and the piston.

No spacers on the small end, if they rods are crank steered.
 
Email sent, thx.



Thanks, nice. Does that mean I don't install the little end spacers that came with the Wiseco piston kit? The ones that go in between the rod and the piston.

if the rods are crank steered, you don't need them (but they wouldn't hurt either).
 
Don't need a machine shop to tell you if it needs bored, just buy a set of telescoping guages and measure the bore in the thrust direction and perpendicular. Check against specs and make the call.
 
Mine is 8.5-1 I don't suffer any of those characteristics. Have you driven an 8.5-1 car to know what your talking about or just repeating what you've read on the all knowing internets?

Higher compression ratio does result in more thermodynamic efficiency, meaning more power out of boost. Doesn't mean your car wont run with lower compression. Higher compression will be more prone to knocking meaning without a proper ignition map for the compression your ECU may pull timing and negate the gains from higher compression.
 
Higher compression ratio does result in more thermodynamic efficiency, meaning more power out of boost. Doesn't mean your car wont run with lower compression. Higher compression will be more prone to knocking meaning without a proper ignition map for the compression your ECU may pull timing and negate the gains from higher compression.

Lol pull timing, I run microsquirt sans knock sensors. It's been a joy since I've lowered the compression back to 8.5-1. I tried tight squish, I got tired of changing head gaskets, the head got so thin the timing belt was getting loose. It'll turn over the 275/40/17' hankook rt615's no problem 3.35 1st gear T5/3.91 rear modded G80. B21F+t, B21 intake manifold.
 
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