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This link claims that a forged crankshaft and rods are used.

4Pistons in this link talked about upgrading the rods but no mention of upgrading the crankshaft itself.

4Pistons also talks about the cylinder head and valve float starting ~7,300RPM in this link.

My takeaway is that the CTR has a forged crankshaft that is solid since engine builders have not upgraded that part as far as I am aware (unless there is a stroker kit upgrade). If other internals are forged, then those same engine builders identified areas that should be upgraded at some point.

Interesting reads thank you. The 4 piston guys were saying they had people bending rods at 400hp!

That's scary.
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Cueyo

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This link claims that a forged crankshaft and rods are used.

4Pistons in this link talked about upgrading the rods but no mention of upgrading the crankshaft itself.

4Pistons also talks about the cylinder head and valve float starting ~7,300RPM in this link.

My takeaway is that the CTR has a forged crankshaft that is solid since engine builders have not upgraded that part as far as I am aware (unless there is a stroker kit upgrade). If other internals are forged, then those same engine builders identified areas that should be upgraded at some point.
Lol I tried Google searching quickly and this thread came up as a source in the ai search 🤣

I also found this article claiming the rods were "heat forged" https://www.hotcars.com/honda-built-one-of-the-toughest-turbo-engines-ever-sold/
 

blueroadster

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Interesting reads thank you. The 4 piston guys were saying they had people bending rods at 400hp!

That's scary.
I would guess that bending rods at 400hp was more caused by the tune and load at lower RPMs. From what I have learned (tune dependent of course) is that the OEM clutch can support up to ~450tq which is quite insane.
 
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Interesting reads thank you. The 4 piston guys were saying they had people bending rods at 400hp!

That's scary.
I'm still convinced they're spewing crap here. If you're bending rods at 400hp, then you're tuning the car wrong. It makes more sense to me that they just bumped that torque to some crazy high number and said that was the true limit
 

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I'm still convinced they're spewing crap here. If you're bending rods at 400hp, then you're tuning the car wrong. It makes more sense to me that they just bumped that torque to some crazy high number and said that was the true limit
It depends where and how you're asking for it...

400+ wtq at 2500 rpm is hard on the rods and will probably cause issues if you floor it in a higher gear at 2-2.5k rpm. 400+ wtq at 4k rpm? Not an issue. As a couple others have stated, the question is more complex than the peak number.
 


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I was looking at some type R videos and got curious when I saw that the lead engineer for the type R said (and don't quote me on this, think it was from a savagegeese video) that the team had extracted as much power from the k20c1 as they safely could. That makes sense for a 4 cylinder turbo, but when you start looking into how people have modded the vehicle and what they've reached presumably in a safe manner, the engine is stable into the 400s and even some into the 600s (HP). Yes, the cars running aftermarket turbos and 35lbs of boost with ethanol may not last at 600hp without building the engine - but that still doesn't change just how much more headroom there is on the k20c1 that the engineering team never wanted to push.

I remember reading this article a few years back about the limit being much lower, but in hindsight the article kind of reads like an advertisement for the shop. Forget the name exactly. Even if we conservatively cap the stock longblocks headroom at some lower torque number (say 400lb/ft) and max power at 500hp, it's still wildly different than comparable 4 cylinder turbo motors.

The Elantra N(2.0L), stock 276hp/289lbft of torque. The TCR engine variants here max out at 420hp and last about 25km (according to Hyundai) at these power levels. Most people never really safely push these past 350whp.

The VB WRX(2.4L), 271hp/258lbft of torque. Saw some people say 600hp, but this seems like a fluke. Overwhelmingly (since the rods and pistons are cast apparently) the top end is anywhere between 350-450hp, which is a really wide range. The general recommendation is no more than 350whp here as well.

Mercedes Benz A45S(2.0L), 416hp/500NM of torque. I believe this was the highest output stock 4 cylinder engine for a long time (might still be). Interestingly enough, the top end mechanically on these is a vague 1000+ (seems more like a tuning test by some company). Most seem to run these at a max of 600hp, but 500-550 seems to be the reliable upper end. Very vague here since I can't find a concrete answer.

Focus RS(2.3L), 350hp/350lbft of torque. People have pushed these to over 450hp, but seems like the consensus is 400hp safely.

Toyota's T24A-FTS would also be included, but thats not a performance engine.

I'm taking in pretty vague terms here since the only people who truly know the engines stock internal capacity are the manufacturers, but it doesn't change that it looks like honda left a lot on the table. Either that or they thought that nearly 200 HP of overhead was what they needed for longevity. To be fair, I haven't quoted the most reliable manufacturers and vehicles, but it's still an interesting thing of note. I also understand that boost, fuel, torque, and various other factors account for reliability and power.

What do y'all think? I would never actually want to push my car to its limits, but it's fun to see what the limits are and why the manufacturer made them so.
There is a class of racing that uses only Type R..The main supplier of these cars sells them for $229000 each. They have sequencial gearboxes, paddle shif actuated. They haveextensive suspension mods...AND...they are tuned to 345 W.H.P.!!! I wonder why??and these cars weight 2900 pounds..and go like real fast..for long periods of WFO throttle...
 

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There is a class of racing that uses only Type R..The main supplier of these cars sells them for $229000 each. They have sequencial gearboxes, paddle shif actuated. They haveextensive suspension mods...AND...they are tuned to 345 W.H.P.!!! I wonder why??and these cars weight 2900 pounds..and go like real fast..for long periods of WFO throttle...
Are you referring to TCR? If so they're limited to around 340 hp and 300 tq.
 

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Correct..but if one is paying $229000 for one and the WHP is 345, one may consider that as a reasonable limit for very reliable day in, day out longevity..just sayin..The FL 5 has a muich better platform in stock spec than most could ever use on a track..let alone on the street..and if a racing platform costs $229000, then my heart, my heart.
 


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Lol I tried Google searching quickly and this thread came up as a source in the ai search 🤣
IMHO, that is not a good sign at all for many reasons.
 

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Cognitive offloading to AI is a concern (MIT Study). Mytopia, dopamine, reduction in critical thinking skills over time are additional concerns.

If those are not checked, then IMHO it leads to smart people no longer willing to share their knowledge. For AI to be helpful, it needs to be locally trained from a reliable/trusted dataset and not simply scraping subjective content posted on the Internet. I love reading engineering research/content posted by experts in their field but fear that their content will be diluted or simply no longer shared.
 
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Cognitive offloading to AI is a concern (MIT Study). Mytopia, dopamine, reduction in critical thinking skills over time are additional concerns.

If those are not checked, then IMHO it leads to smart people no longer willing to share their knowledge. For AI to be helpful, it needs to be locally trained from a reliable/trusted dataset and not simply scraping subjective content posted on the Internet. I love reading engineering research/content posted by experts in their field but fear that their content will be diluted or simply no longer shared.
At my work the company has been really pushing AI (mind you, I'm an engineer) and anyone who parrots the company pro-ai views gets praise even when the more skilled technical workers dislike it. Had a coworker the other day who's been at the job for less than a year rant in a pretty big team meeting about how he starts his day by turning on ChatGPT. Said he thinks the future was to replace learning from your peers with ai learning. Kinda made me really angry.
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