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K1 Technologies rod experience?

Its not so much the power, but the cost that my engine has summed up to be so far. I'd rather buy a proper set of rods than save a few quid and worry about one letting go from sustained abuse at high RPMs.

To answer the question regardless, about 230+ NA

Those are I beams. Just get some rods from Yoshifab
 
Just for reference, the speeding rods are actually pretty good. I ran them in my Audi AAN 20VT 5cyl at 32psi and my rev limiter was 8200rpm. I banged it off the rev limiter doing donuts on the regular, thing ran low 12s at 4300lbs with me in it and an old school quattro drivetrain (~25% drivetrain losses according to Audi builders in Germany). I've run them in other more boring cars too (5cyl whiteblock builds of various levels)
If you buy K1 rods, they come from the same factory, just so you're aware. Until K1 updated their packaging, they came in the same box with different printing on them. Like, as in if they didn't pay the factory to laser etch "K1" on them and you set one down on the table with a maxpeedingrod, you would have a hard time figuring out which one is which.
Biggest difference is that K1 cleans up the rods before reselling them, with the Maxpeedingrods you sometimes have to clean and deburr them a bit. K1 is even careful on their website not to claim US or European manufacture. They basically say that they are import rods, but theirs are better because they clean them up. Not worth the difference in price IMHO. I even run the speeding rods with the "ARP" bolts they come with. Next to an ARP I can't see a difference, they claim they're real ARP but ARP doesn't have them listed on their website as a rod manufacturer. Either way, they hit the stretch target at the expected torque and they hold up fine.
 
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Just for reference, the speeding rods are actually pretty good. I ran them in my Audi AAN 20VT 5cyl at 32psi and my rev limiter was 8200rpm. I banged it off the rev limiter doing donuts on the regular, thing ran low 12s at 4300lbs with me in it and an old school quattro drivetrain (~25% drivetrain losses according to Audi builders in Germany). I've run them in other more boring cars too (5cyl whiteblock builds of various levels)
If you buy K1 rods, they come from the same factory, just so you're aware. Until K1 updated their packaging, they came in the same box with different printing on them. Like, as in if they didn't pay the factory to laser etch "K1" on them and you set one down on the table with a maxpeedingrod, you would have a hard time figuring out which one is which.
Biggest difference is that K1 cleans up the rods before reselling them, with the Maxpeedingrods you sometimes have to clean and deburr them a bit. K1 is even careful on their website not to claim US or European manufacture. They basically say that they are import rods, but theirs are better because they clean them up. Not worth the difference in price IMHO. I even run the speeding rods with the "ARP" bolts they come with. Next to an ARP I can't see a difference, they claim they're real ARP but ARP doesn't have them listed on their website as a rod manufacturer. Either way, they hit the stretch target at the expected torque and they hold up fine.

I'm not entirely sure what you're talking about regarding the laser etching on the same set of rods..?

If you open the link I put in the first post, those rods look nothing like the speeding rods? Yes, if you google "K1 B230 rods" then the speeding rod clones come up, but those aren't what I'm on about..
 
If the rods are equal weight, I’d choose the I-beam rods any day (as long as the price isn’t 4x).
K1 rods are used in high rpm Honda k-series builds without issues. I think the quality is fine.

The only reason to choose the h-beam rod is the price.
 
I can see that they're I beams in shape, but material quality, end to end balance, and overall product reliability is surely far more desirable in the K1 rods than the generic Yoshifab rods?

The cheap Chinese rods and Yoshifab rods are pretty darn good with overall weights and end weights. Usually well within 1-gram. Material is 4340 as stated by the manufacture.

Overall, the cheap rods are a great bargain? and a really solid product. I would personally prefer a good i-beam over an h-beam.
 
I'm not entirely sure what you're talking about regarding the laser etching on the same set of rods..?

If you open the link I put in the first post, those rods look nothing like the speeding rods? Yes, if you google "K1 B230 rods" then the speeding rod clones come up, but those aren't what I'm on about..

Sorry, if I-beams are what you need for your application then sure, the K1s are the ones to use.
But they're made in the same factory as the speeding rods. It's just a big factory in China that makes forged rods for K1, Eagle, Scat, Yoshifab etc...
Your "few more quid for nice rods" are going to the same place in China, and your rods are coming from that same place. Anyone making "really nice" rods not in China will explicitly state where they're made, not beat around the bush with ambiguous terminology.

My experience with a side by side is with whiteblock rods, I had a set of 139.5mm whiteblock rods here from K1, and a set from Maxpeedingrods and they came in the same box (with different branding, of course, but even part number labels were the same format), packaged the same way, both made in PRC, same bolts, same machining, etc.

If you need an I beam, get the K1 because I don't see anyone else selling it. But for your application (less than 300hp) and presumably spinning less than 8500rpm, the cheap H beams would do fine. I've weighed them end to end and they've always been remarkably consistent within a set. I've run them over 100hp/cyl and over 8000rpm and the set in my audi had the 5/16" bolts. I wouldn't hesitate to run them. KLracing sells 158mm versions of them (in crank steered or piston steered) for not a ton of money.
 
The cheap Chinese rods and Yoshifab rods are pretty darn good with overall weights and end weights. Usually well within 1-gram. Material is 4340 as stated by the manufacture.

Overall, the cheap rods are a great bargain? and a really solid product. I would personally prefer a good i-beam over an h-beam.

See, I've always heard good things about the generic H beam rods from whatever supplier is chosen, as has been mentioned, they're all from the same place at the end of the day! I'm sure if this engine build was a budget build then they'd be what I keep, but I think I'll only be using them for the dry build, and use some better ones when I'm ready to run it.

Sorry, if I-beams are what you need for your application then sure, the K1s are the ones to use.
But they're made in the same factory as the speeding rods. It's just a big factory in China that makes forged rods for K1, Eagle, Scat, Yoshifab etc...
Your "few more quid for nice rods" are going to the same place in China, and your rods are coming from that same place. Anyone making "really nice" rods not in China will explicitly state where they're made, not beat around the bush with ambiguous terminology.

My experience with a side by side is with whiteblock rods, I had a set of 139.5mm whiteblock rods here from K1, and a set from Maxpeedingrods and they came in the same box (with different branding, of course, but even part number labels were the same format), packaged the same way, both made in PRC, same bolts, same machining, etc.

If you need an I beam, get the K1 because I don't see anyone else selling it. But for your application (less than 300hp) and presumably spinning less than 8500rpm, the cheap H beams would do fine. I've weighed them end to end and they've always been remarkably consistent within a set. I've run them over 100hp/cyl and over 8000rpm and the set in my audi had the 5/16" bolts. I wouldn't hesitate to run them. KLracing sells 158mm versions of them (in crank steered or piston steered) for not a ton of money.

Honestly, the cross sectional shape doesn't have too much relevance in my application as you have rightly pointed out, my power levels and RPMs aren't high enough to warrant thinking about it too much.

At the end of the day, I'm about ?5k into the engine so far, and while the PRC rods are absolutely fine, I just want to buy a set of rods where I know of the QC processes, and can call them up and ask why one let go and wiped out my block if things do go wrong.

If what you say about the K1 I-beams is true that they're also from the same factory as the rest, then I will give them a miss. I had made the false assumption that the price tag they carry reflected the fact that surely they'd be USA made!

I might get in touch with arrow precision or similar if I have no luck finding a better alternative.
 
I know that JohnV advocated for longer rods and shorter pistons, but that is about all I can contribute to the discussion
 
I know that JohnV advocated for longer rods and shorter pistons, but that is about all I can contribute to the discussion

I had purchased longer 158mm rods from Yoshifab, but my engine shop has advised against using the generic speeding rods stuff, which is why I was looking for an alternative place that offers high quality stuff :???:
 
I had purchased longer 158mm rods from Yoshifab, but my engine shop has advised against using the generic speeding rods stuff, which is why I was looking for an alternative place that offers high quality stuff :???:

The quality from the generic rod suppliers is incredibly good BTW. You might have to add some oil clearance on the small end depending on what your plans are, but that's what every engine builder/machine shop does anyways.
 
Yeah, the shorter piston thing...BTDT, won't do it again, that sucked big time for far too long.


MTOD did an Engine Masters on long vs. short rod design, didn't equate to much difference at all.

I mean you cannnn get pistons with longer skirts and use a longer rod still. But yeah, short skirt pistons and higher PTW clearance is a recipe for wear and disaster.

And yeah, rod length doesn't matter too much unless you're making MASSIVE changes or looking for a small change in an area.
Generally 1.6-2 is a solid spot to land in for rod/stroke ratio... Stock 152mm rods are 1.9 (152/80), which is well in the good spot... and arguably too long as it is.
 
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