I wasn't made for these times. A man of my own heart, racer mechanic yet he speaks in upspeak.

I don't own a Dodge but still love the channel for all the information that is shared. I am always baffled as to why this channel doesn't have a 100k plus subscribers. I watch tons of performance and automotive related channels and yours is one of the best by far.

People most often think about the tremendous forces applied to a piston and connecting rod when a cylinder fires. But what's often forgotten are the tremendous forced applied to a piston and connecting rod when the piston goes up at high speed speed and then has to come to a dead stop before being pulled down again at high speed.

As a Hellcat Owner, I just subscribed to your channel. Your content is much appreciated!!! I look forward to the what's to come this week. Thanks for sharing.

Thanks for going through the trouble to show us what exactly happened to this engine. Very interesting.

Wow, a floating piston during a quarter mile running 10s...probably just built for 6k rpm on a factory motor of 800hp, running 7k rpm on stock rods and pistons will give on a Hellcat...lesson learned..forged pistons and rods built for racing...great video along with data logging of the failure 👍

That piston isnt "forged", or actually extruded, its a casting as it has cast in numbers inside the crown. It was simply termically/mechanically stressed beyond design parameters. Amazing that people expect them to survive racing and that they actually do in many cases.

Excellent input! I had a cylinder 2 fail on mine and found it out from the Buyer of the car as I did not want to rebuild the motor - so I sold it! Blessings for future success!

Exceptional video for all the reasons you stated! I have had 2 engine failures (different platform) - but all of the detail you are sharing here is great along with your and others theories!

I haven't delved far enough in the performance side to have an opinion, but I appreciate the information you've stated here, it'll definitely be useful in the future when I begin engine mods on my R/T. Thanks for taking the time to share it.

Might have just been a perfect storm of stuff. Defective piston cast and cylinder just a bit out of round. Like you said these are mass produced parts. Quality control isn't as detailed oriented when it's a numbers game. Doesn't make it a bad product but it is man made. We haven't made anything that is perfect all the time. Great detective work and thanks for putting it out there.

When metal parts fail, it is almost always at a sharp corner. Threaded parts fail at the root of the thread. Parts with grooves fail at corner of the groove. That's why these type of parts are engineered with a radius at the root of threads and corners of other parts. The larger the radius, the stronger the part. A sharp corner causes a stress rise in the part. It is possible that the oil ring grooves of some pistons have a sharper corner than others, caused by tool wear during production. Also if the oil passages have a sharp corner where they meet the oil ring groove, it would cause a strees rise and potential failure spot.

All I see is too much timing or too much heat in that cylinder. The cylinder got super hot and seized up the piston. That’s why it’s all blue at the bottom. Haven’t built many Hemi’s but I’ve seen this on LS engines where one of the cylinders got too hot. Appreciable you sharing this with us.

I agree with the comment/ theory that all the parts and engines are "mass-produced" and that could be the issue. In "blown" engines (positive displacement and or turbo supercharged or composite supercharged & turbocharged engines) the smallest of issues can become major issues in a heartbeat. I have built and raced and maintained 2 and 4 stroke motorcycle road racing engines as well as 1, 2 (twin) and 4-row radial military aircraft engines prior to computer data logging abilities and had to rely on post-event evaluations as to why engines failed. I would personally believe if I had to point to a single item/ issue it would be the cost-saving measure of the factory not using a torque plate while boring/ honing the cylinders. The difference is tiny by any standards but "can be" significant during the extremes encountered by any engine not designed from the onset as a "blown" engine. The levels of stresses involved accelerate so quickly and suddenly that it can be almost impossible to catch.

I will go with skirt cracked, piston rocked in the bore on intake stroke, and the rod pulling it down ripped it apart.

Great video Speedy, very informative and educational, Goodluck with the new build and keep putting out informative content.

Im giving it a thumbs up speedy, but being a Hellcat owner myself it makes me sad.

The JB Weld piston I ran in my lawnmower did the same thing, tore the piston pin bosses out of the piston after 3 minutes of grass cutting. I have suspected for years that pistons/rods in a 4 stroke engine usually fail when the piston is snapping over TDC between exhaust and intake stroke, as the gas loading on the piston is much less than during compression stroke. Thus the rod/piston would suffer a tension failure at this time versus during the power stroke when the expanding gases would push against the piston counteracting the inertia forces of the piston deccelerating approaching TDC. Just my 2 cents. I also wondered the same thing, as #2 cylinder follows #7 firing in a normal 1,8,4,3,6,5,7, 2 V8 firing order. Forgive me if the Hellcat uses the modified firing order where 7 and 4 are switched.

Speedy you are definitely a racer. Awesome video. I agree with your gut feeling that it was a defective piston. I know you push your engines to the limits with your mods, but you do it by the book. So much to learn from here. Sadly, I don't think it's anything you did wrong, just a defective piston. Thank you.

Excellent information brotha, thank you.

If you broke the ceramic on the plugs its from knock. It was the tune. The ceramic on plugs don't break unless there is detonation.

Race Engine Builder here, and trust me guys, I'm not going to try and be the know it all bully. In FACT I am not even going to make a guess on what happened since I can't see the parts in person, or mic things up. Now what I would like to add is that here's where, in the future anyways, a inexpensive knock sensor attatched to each cylinder head may have helped. Any Engine Builder that runs his own dyno, will or should have at least 1 knock sensor. This will save a engine from catastrophic failure as much as oil pressure, oil temperature, water temperature, etc. A boosted engine especially without a knock sensor is inviting the potential for a devastating failure. Again guys, just my humble opinion from 40 plus years of dyno tuning.

Great video! Thanks for sharing the knowledge gained from the failure. I certainly agree with your theory. The point you made previously stands: if you race, you best be prepared for things like this to happen. Thanks again for the way you present your format!

I was thinking all along what you said at the very end of the video. I think it was that hot intake air temperature that did it. Piston and rings swelled up inside the bore and made that piston a little too hard to pull back down and it just ripped the skirt right off. That had to have been what happened. You got to realize, the temperature you’re seeing coming into the engine that’s all the way up in the intake. By the time you go to compress that gas before it is ignited it’s only going to heat up even more! When you compress gas together rapidly it heats up rapidly, even without igniting the mixture. By the time the spark plug hit that intake charge was surely a few hundred degrees more, if not over 1000 degrees. Plus, your back cylinders are always going to run a bit hotter than the front ones, they’re the last ones to see the coolant in the block before it goes through the cylinder heads and is cooled through the radiator. Was the engine sitting and allowed to cool way down between passes? We all know that metal expands when heated. That’s why they say to never flog a performance car when the engine is cold. Everything needs time to warm up to operating temps to allow the tolerances to tighten up. Hope this all helps

I did the exact same thing to my 1985 S-10 2.5L Iron Duke motor by putting it in neutral and flooring it, seeing how high it would rev. It rev'd pretty high... then BAM... piston exploded. In my case the entire piston shattered, then I had just the rod and pin rattling around in the cylinder.. it was SO LOUD, but awesome at the same time. Good Times!

I am a small engine mechanic. This was caused by a bad batch of aluminium. Once back in 1990 I had 12 hp Briggs and STratton engines that would stick intake valves open on brand new engines. Briggs and Stratton called it "Porus casting" from february to april that year, it was aluminium engine block, they warrantee short blocked the engine, and another that had done the same thing on another mower in the shop. That piston swole up, and Heat from combustion would do that. Only the faulty ones will do that, you gonna have to know the manufacture dates from your failed piston, and replace all with that manufacture date. Porus casting of the aluminium piston. You can open the ring end gap, you can bore the cylinder larger, none of it is gonna work because you can't tell how much that porus casting it gonna swell, its an unknown variable. Bad batch of aluminium... You gonna run 9's you need forged or have lots of room for expansion, can't run close tolerances, gonna have to open all that stuff up so it can swell up at high speed. Loose is fast!

Similar failure found on entirely different engine. Found oil squirters for piston blocked, overheated piston momentarily locked ripping wrist pin out of bottom. Remaining lower portion disintegrated so rod and wrist pin were flopping up down in bore. Rod was long enough that didnt jam and break but still had bend poss due to hitting debris and piston top. In this case heat was the killer.

Ha ha ha you had me for a minute on the floor coating! Great info and video on the failure! Thanks Speedy.

You hit the nail on the head,mass produced parts !

Thanks for showing us. Enjoyed the video.

Thanks for the great info. Im thinking of the same upgrades this winter. I differently going ti looking into the pulley(tune), driveshaft, tires, & full exhaust. I just want low 10s. Thanks again bro

If your a racer then build them with better aftermarket pistons and rods, much better 1000hp+. If you stay stock then expect these kinds of problems.

Very good video. Really enjoyed. You do a great job. Thank you.

The pattern of breakage on the piston looks like fatigue failure. Usually has a dull, satin type appearance from the cracks gradually progressing before it fails catastrophically. The final sudden fractures will be more shiny and metallic in appearance. That's also where you'd expect to see it. Those holes are at least drilled and not cast slots, but still they are stress risers.

the quote on your shirt is actually something to live by

Just a failed piston. I think its a fluke. I believe the factory pistons are actually manufactured by Mahle. Not junk. Those guys know there stuff. My Buddy works for CP Pistons and has nothing but good things to say about Mahle. Id love to see the difference between a Demon/Redeye Piston and Rod assembly versus a Hellcat.

At 4:42 it looks like your little shop helper (your cat) decided to come in to help you. Looks like a Tortoise Shell cat, I had one for 18 years and they are wonderful cats :-)

I appreciate this video so much. thank you!

Awesome content bud, I have been wondering about my hellcat. I'm making good power and wanting more but it's a daily driven vehicle. I have almost 40k on it now but I did the pulley swap and tune with Petty's Garage. They did a great job with the setup but they left a lot on the table. The swap was done at almost 15k miles, another company said they can get me over 975 from their tune only with what Petty's did. Thanks for your information on what your vehicle did. Keep it up and can't wait to see what happens next. Good luck bro

Good video. Appreciate the details. I have a 2016 Hellcat myself.

Ya have a sporting man's attitude, good on ya! Sorry to see GoManGo down but thanks for sharing your experience/investigation.

Great video, thanks for showing what went wrong 👍

That happened to a 10,000 mile 4.6 Ford 2v that I owned. Plug pieces scattered and welded to the piston top. I was running a Vortech with no intercooler racing on a hot summer day. The rod came a knocking on the block lol. It took out my valves as well so I needed a total rebuild

Looks like the pistons use an offset pin which is great for making torque...but it also increases the side thrust on the skirts. Anything with offset pins to me means you really watch the RPM's and never exceed the factory redline or skirt failures will happen. Bet aftermarket pistons are symmetrical pin design which will hurt the bottom end torque production a bit but will be more reliable at higher revs.

Ty for the time you took to share this GReat informative video rock on

I'm not a Hellcat guy, but enjoy your channel content. From my big block chevy days, I would have attributed that failure to insufficient piston ring gap. As the cylinder gets hot, the rings expand, ring ends butt up, ring continues to expand. Ring acts like a break and attempts to stop the piston in it's bore. The rod is still pulling the piston down, the piston breaks at its weakest point, which usually is behind the oil rings, where the holes exist to allow the oil trapped in the ring, to drain back inside the piston. Just my two cents.

Great video a lot of good information very interesting thanks

Man lots of good info on this video. Agree with you that people want to sweep things under the rug when things go wrong. (Myself included). Can’t wait to see what you put in there next. Learning from this makes me want to get forged pistons and rods from Callies or some other place like that.

Good stuff man!! Crazy that it would rip it apart like that. That is some seriously high torque to do something like that.

No need to "figure out" what people want to see, IMO.🤔 You're an FCA Hellcat testing lab. 😃 Those of us w/Hellcats, appreciate your documentation!😃

GR8 VIDEO THANKZZ FOR SHARING!!!

great analysis bro, just subscribed

Great video.....knowledge is everything with these motors

Excellent video! Thanks for digging deep and sharing what you found. I have a basically stock 6.4, I'm constantly wondering what the weak links are.

Great video speedy! Now I know we should be worried about when seeing a knock but nothing shown on a knock sensor could be indicating a serious bottom end problem !

Over 60% of the late model Hemi i have re manufactured (aprox 25 longblocks) had failed due to intake seats coming loose and breaking. If your rebuilding an engine with a seat failure make shure you pressure wash your intake manifold really good. Try to get every port from every angle possible. There have been reports of fresh rebuilds pulling pieces of broken seat debris into the cylinders under heavy vacuum scenarios. Some after market gaskets have a screen embedded in the intake gasket to prevent this from happening, but im shure they will adversely affect top end performance. Any sign of issues i remove the seats, machine and install new seat inserts. If there not getting replaced i will steak around the seats using a center punch to ensure the dont move.

I think you are right, since the parts are made for mass production you will see stronger than spec parts. Parts that meet but don't vastly exceed the tolerances dodge specified for the order may fail unexpectedly.

Sorry for your problem Speedy. I'm a hellcat owner also, and in my opinion the entire car is a piece of Garbo. I continue to have tranny issues ( a 6 spd). The only impressive item in the car is the sound system!!

EXTREMELY WELL DONE ANALYSIS AND I BELIEVE U CALLED IT CORRECTLY

Great video,I have a ktm 690 engine on my bench with similar damage,I have theorized on what may have caused it but not really come to a strong conclusion....nice info in this video

RPM kills engines. I have seen this on any engine a lot with floating wrist pins. Pistons with hardly any skirt and floating pins rock more and will break and leave the piston at the top of the engine. Piston ring gaps can also close tight and leave the piston at the top. Floating pistons get get larger as time goes by and when they jurk the piston back down can break the piston or rod. When you press any engine to its limits you can expect anything to break after time. Just the way the game is played. Its a money game if you can afford to play.

Do you still have the data logs when you were at the track when it was blowing through the shift points? I'd like to take a look at them, I have a few things I'm curious about.

Hellcat engine failure at those rpm’s doesn’t surprise me at all !RPM is what kills an engine.A lot of good content here !

Awesome video!!

too much heat , expanded the rings untill they butted, seizing them in the bore, breaking piston tops. Guys who get carried away boosting LS engines without opening the ring gaps have this problem, too.

110% sure rpm did that. Did that to a 440 many years ago. Went to down shift 2nd, went straight to 1st at 60 shot to about 80 before I got back to third. '70 'Cuda 440 + 6, 727 Torqueflite with B&M shift kit that allowed shifting into first at any speed. Started burning oil, a couple weeks later, 7,000 rpm shifting into 2nd, whoose!!!! Three rods out the side of the block. One rod swung up into valley broke the back half of cam off. Had one piston that yanked the pin just like that, that probably started everything. You probably cracked the wrist pin boss in the piston. Wrist pin yanked right out of the piston. Combined with a possible Monday forged piston. Thinking that piston was just a weaker piston. Nice autopsy, thanks.

Haven't seen any of your videos before - very well done and excellent points raised! High ring pack is for emissions and power, lower is for top land strength. Were you able to check the remains of the connecting rod small end - if it failed it may have allowed the piston to rack sideways a little, stressing the pin area of the piston until it failed? I think, though, you and your buddies called it, though - poor piston quality allowed the 'pin bosses to fail.

The one time that happened to me was in my slant 6. I over heated the engine and a piston seized pulling the rod from the piston and putting a hole through the block. I suspect that pistons tolerances were a little tight and subject to heat. If you race, build your own engines. I've raced for 30+ years. MOPAR!

piston skirts are way too short! yea they tried to reduce the mass... but!! you can only do that on engines that are race only!! trust me!! been there and done that back in the late 1970's!! also burned plugs. is bad fuel! advance issue!! I used to run 49 deg advance back in the day... got in to some wrong tagged fuel... these are the reasons they check fuel at the drag strip... high rpm, advance walking, bad fuel = broken parts!! forged pistons are the only way to go!! I always liked aires brand... custom were only were 400.00 each. that was back in 1980!! 100% perfect spec!!

Awesome Speedy《☆》Definitely a Parts Lottery with stock Hemi engines. FCA needs to re-evaluate parts suppliers & quality control. The 6.2s are having piston issues and the 5.7s are having lifter/cam issues. Good luck with GoMango🤓☻🤠

On my trackhawk Snapped my rod one #1 and it dropped a valve in that same cylinder. I was about 1k hp. Just got my new built engine in now doing tuning shake downs now

Only time I've seen failures like that is due to pinging piston rocking in The bore if the piston was cracked you probably would have heard for a while before it failed. And the melted spark plugs seems like a tuning issue to me.

Great Video and information related to your major engine failure. Semper Fi....

Great video speedy thanks

Is it possible the gudgeon pin lock on one side failed and the gudgeon moved to one side and twisted the piston

I had a piston come apart at the Oil Grove rig on a 1963 Olds Cutless 50 years ago!! Noth-N new here!!!

Buddy has a new Hellcat, a rear wheel bearing failed at 3000 miles. He says the warranty specifically excludes wheel bearings.

You guys are kicking the heck out of those motors. It's amazing they survive what they do. That you ripped the skirt off a stock piston is not surprising.

Looks like you had some piston skirt damage and rocked the piston till it let go from what the crown is showing. But you didn't show the skirt pieces which is probably the most important pieces to look at. The top 2 ring groves look too good for it to be expansion seizure. Well that and the fact you sucked the crown out with a shop vac

What's amazing here concerns the piston failure. Normally then, the rod-end, with wrist pin, slaps like hell in the bore, wiping out the bore, and therefore the block itself. I've actually NEVER seen a piston failure where this didn't occur until now...(First time for everything?)

Excellent vid. LIKED.

Don't apologize for the length of the video.... I actually prefer the longer videos!

I've seen plenty of pistons break at the oil ring groove on different makes. It's high RPM on a part not really designed to live at those piston speed per mile speeds. Mopar built these cars so folks could race them and live with the damage and develop the engines to make power and live a little longer themselves . it's a story as old as the car.

Good job my friend. Very well done video. Thanks. Going to make me careful with my Redeye.

My buddy had a 318LA that had a similar problem, except part of the piston skirt broke off and wedged itself in the cylinder walls (It's on my channel) and it seized up the wrist pin on that cylinder and a few others, our guess was that it was ran low on oil at one point and when he got it (and he ran that thing hard) that it weakened it up causing it to fail. Could have been as simple as bad lubrication at that moment

Great presentation. Subscribed

Its RPM.. and too much for the pistons.. Im a ford/LS guy and every time I have seen this type of piston breakage it has been from over revving the motor.. I have buddies that shift their coyote's at 8200rpm, and they quit making power at about 7600 to 7700.. and they all experienced this same style damage.. Your motor is a torque monster, just shift it and enjoy that low end..

I'm impressed, great analogy you breezed right through it. Don't forget to stop at "Go" and pick up your 200$ 💰

The demon engine got all strengthen internals. Wish hellcat had it too

Totally agree and like said in old comment... the hellpuss is not torque plate honed and I have seen two that seen 7000+ with wrist pin pulling out back of piston diamond pistons in the new set up with alot more bottom end also threw the blower in the corner added twin 88 ball bearing percisions added fuel injector bung to a sheet metal intake I built for the car.. the factory rearend let go on last dyno pull we knew it was on deck before we even started the tuning that hellpuss put 1691 down and still has more in it good luck with yours like the vidga

Decent channel, kept me interested, I should def get back into chasing 9's with ya, good luck man

This was a fascinating video.

I wish someone would help me pay for my engine mine just blew a piston threw the bottom of the block 😒 am sick over this as my Hellcat challenger is my baby. Your videos are very informative and learn alot from you!

piston rings butted, the crown of the piston is strong enough not to chip off so it sized the piston in the bore, pulled the wristpin out of the piston. rear cylinders run hotter on pretty much any engine due to the coolant inlet being at the front of the engine. couldve gotten one that was on the tight side of factory acceptable piston ring end gap clearances, and then turned the wick up on it.

What kind of floor coating do you use in your shop?

been here since orange crush, have learned SO much, thanks Speedy!!💪😎

Super video ... The longer ,the better 😀

I rarely subscribe to channels and not really a Mopar fan but I enjoy your content. +1 sub

I have a 1954 354 Fire Power hemi and a buddy of mine has a hell cat hemi. I was blown away at the differences. Even the way the bearing caps are split. But yeah I'd say a fluke of a failure. Me old school carbs and engine, no juice so no "check tunes data". Seems to me some major piston slap tore it apart at high revs.

thanks for the tip