Piston to Valve Clearance

In this video I explain all the myths of Piston to Valve clearance, how it really works and what yours needs to be!!

[@nadronnocojr]

Imagine if going to school each day consisted of this kind of learning in the 80’s I would have been a honor roll student .. I’m addicted to these videos You speak y language thank you for these videos sir

[@3800TURBO]

My engine shop teacher was a Prostock racer. Helped me assemble my first engine. I learnt more from him than the actual school.

[@J-RocksCustoms]

For visual learners, his methods of teaching are great! I work in the nuclear industry and a lot of times I have to hit the “I believe” button because you just can’t see everything. But if it’s something I can see, I understand it 1000% better than the best “read and learn” student.

[@jimgiordano3613]

Amen.I learn a lot from sSteve.

[@Bigcheif360]

You are the Einstein of the engine world. These videos are always so in-depth. Great work.

[@VeritasEIREAequitas]

This is amazing to have Mr Morris sharing this knowledge for free. Great stuff from a legend

[@mrd.808]

Love what Mr. Morris is doing. Sharing his knowledge and experiences = priceless!!!

[@firestorm755]

Steve you've a knack of explaining complicated stuff so as ordinary people can understand it!

[@TurbineResearch]

About to build a motor. I'm glad I saw this

[@hankclingingsmith8707]

I LIKE THAT YOU ARE AT THE TOP OF THE GAME OF MOTORS, AND THAT YOU ARE NOT ARROGANT ABOUT IT

[@memra777]

Thank you Steve for humbly sharing - you are making advanced engine building knowledge accessible and enjoyable for the average person.

[@bonzainews]

First time I have seen this subject demonstrated on KZbin. It's been 25 years since I watched my engine builder check my engine's clearance.

[@flyin5j]

Super good lesson! Building my first aluminum block 410 sprint car engine, big Learning curve. Thanks for the videos!

[@Matty.Hill_87]

Hows the build going?

[@bradgeary3467]

dynamically it’s .0015 interference, but it didn’t interfere because everything stretches and lags. I could see all that as you described it. 🤯 . absolutely fascinating. thank you for that. what a precise yet chaotic and harmonious game of precision you play. Very cool stuff

[@stevemorrisracing]

Thanks

[@nicholasprusko9590]

Thanks for all these videos , they really help demystify these concepts.

[@apollo5751]

The knowledge you just unleashed.. WOW

[@magnus5356]

Very interesting info Steve. Thanks for sharing!

[@myrondel]

Hey Steve, Thank you very much for your instructional video series. You've done an excellent job explaining a lot of difficult-to-understand events that occur when building and running a high H.P. engine. I think the word you've been looking for during this series of videos is "longevity", not criticizing you in any way, just trying to help. Seldom do you find someone that possesses and is willing to share the amount of knowledge that you have shared with us all, thank you.

[@basketballcory2]

Absolutely love your videos. Currently doing engine teardown for a big figure in the engine world. Learning more from you this far

[@Stormin06096]

Great explaination.

[@shaneshane1379]

You just put a good example of iron block with steel rod versus aluminum block and aluminum rod. I have built lots of engines with the pistons .010 out of the hole to compensate for msl head gaskets. I have no experience with aluminum block but I do understand heat growth and expansion. The best way I can describe aluminum combinations, is aluminum has to be built to grow.

[@Nova-1977]

Great information I was just ready to back up the cam timing because I only had .060 intake valve to piston . Just advancing the cam from 109 factory center line it was in at 109 it had 180 cranking compression moving it 3 advanced it went to 205 crank compression cold . It should help the short time NA small block Chevy .

[@marklowe7431]

What amazes the crap out of me is people like you that make real efforts to share your knowledge. It's such a good human trait. Big thank you. btw, never heard someone describe clearance in this detail. Quench space, rod stretch?

[@LowSRider]

Great video Steve. Keep up the good work 👍

[@MrJermbob]

You make such amazing motors man. I love these videos. Wish we could hang out. Love from New Zealand

[@stevemorrisracing]

Glad you like them! share them to your buddys

[@ChicagoRacerJoe]

0.050” in the hole, does not account for head gasket thickness. Not sure if it’s really a negative clearance but it certainly is much tighter than most would assume.

[@Hogiewan1]

Imagine all of the combinations of metals that go into getting just the right amount of thermal expansion without being too brittle... I suspect that's why a lot of the high end parts are so expensive (not just the machining). Thanks Steve.

[@erikkoenig4037]

Very nice video with a lot of knowledge!

[@89StarquestTSi]

Maybe I missed it but did he explain that aluminum rods will stretch more than steel rods and this should be taken into account when setting piston to valve clearance? I never hear it mentioned by builders and its an IMPORTANT factor in engine design

[@MattyEngland]

Great video. Learned a lot 👍👍

[@JohnRoberts71]

Great content thanks for sharing, very informative

[@mbliss01]

Fantastic the way you share this stuff Steve, thank you. You have just added a nugget and reassurance on how I have thought about this for forty some years. P.S. You didnt really point out how the piston chases the exhaust valve up the bore as it is closing, as opposed to the intake valve chasing the piston down the bore as it is opening. Much of your audience may be aware, but some are just learning.

[@genemounce8302]

JESUS!.... the girth of that rod would make Ron Jeremy blush. ;)

[@nurburgringdreaming2221]

Man there’s so much more I wish he would’ve got into on this subject but it would’ve been a longer video.

[@ntjack8894]

Top video, so much information.

[@smudger6461]

Wealth of knowledge 👍

[@the4flatgarage]

Very informative. Thank you.

[@thedobermangang3503]

Good video my brother

[@danielsmith-ze3wy]

Thanks for video Steve

[@rpturbo]

I'd really like you to go more in depth on how camshaft profile/ramp rate either drives or diminishes the chance of valve interference. I ask because I only have experience with hitting exhaust, another guy I know has only had experience hitting intake. Has to be cam design and setup, right?

[@MattLundquistVW]

Question Steve, why do the valves look like they have been polished to a mirror like surface?

[@johnmckamy6398]

Awesome info

[@hyperglobalmegadude]

Can we have a Steve Morris vs. Tom Nelson motor competition TV show?

[@Kincentc]

No. That would require TV to air good material. They would never

[@bobmcalister2131]

Another great video!!! Can you explain why the ring land lifts up on the intake side.. in a video please sir.

[@stevemorrisracing]

Noted

[@stevekarr4613]

Great tech!

[@2strokecarbtuningportingin187]

Again great you share your information. And again 100 % not easy trying to make vids and explaining this plus you loose compression with to much valve to piston. Does it create valve shrouding

[@2strokecarbtuningportingin187]

Great channel not easy to explain this stuff.but a simpler vid and explanation for valve to piston would be a valve drop on a assembled motor. With light spring and Dial indicator. ??

[@RatRodBobBuilds]

Good info!

[@vw3800]

Thanks for the info

[@juiced71]

Smart man!!

[@oikkuoek]

That valve positioning on these pushrod heads has always baffled me.. How they make any power without forced induction is a complete mystery. Could this modern billett technology create a working DOHC setup for V-layout?

[@davidsabyan2481]

Wow, very clear explanation and tips. I have used both the play_doe and dial indicator method, but I assumed you put more clearance on the exhuast valve because of heat and the resulting expansion. Now I understand how cam timing get retarded as high RPM comes into play. This will win me a few beers bets for sure.

[@vanhap]

so how does this static PtoV clearance apply to 4 cyl interference toyota 3rz engines? In stock form the timing chain rotating the valves out of the way in time with pistons?

[@grantk.3860]

Thanks again🙏

[@FixItStupid]

Thank You !

[@RestorationWatch]

"Latent" is the correct word. 🙂

[@23steph13]

Who makes an A-symetrical cam? Street 6.0/6.2 N.A. LS

[@3800TURBO]

Q if I may. What degree angle would you cut a quench area to soften the chamber for big boost to help supress knock? Love your vids Steve. Ps: I have one bent exaust valve due to bounce lol. Ran a little more seat to help.

[@8180634]

In regard to the timing possibly being different for different cylinders due to the cam and crank twisting a tiny bit under load: are there applications where you specify different valve clearance for different cylinders because the crank-to-cam timing is different due to the twisting, or does it just so happen that the crank and cam both twist proportionally keeping the per-cylinder timing the same, for lack of a better way to explain it? Or is the amount of twist just so small that separate per-cylinder clearance values aren't required?

[@stevemorrisracing]

it does happen, very hard to actually calculate and you would only be talking a few thousands of a inch at most front to back. if more than that you have way bigger issues to handle.

[@Ursus5848]

What do you think of 3d printed pistons for big hp applications? Porsche has recently had some great success with theirs.

[@stevemorrisracing]

Dont know till you try

[@shoominati23]

Steve : can you talk a little on stroke to rod ratios? Smokey used to say, put the longest rod you can in a motor, but modern thinking seems to be the opposite. I get why he might have said that as heads didnt flow all that well back in the 60s and you wanted the faster piston speeds to cram as much mixture in the cylinder as possible .. but what is your take on it?

[@andy347495]

Am I understanding this correctly, no piston to valve to clearance is needed on the intake as far as depth is concerned, only clearance on the radius? If so, at idle and low rpms is there still a "laten" effect?

[@KORTOKtheSTRONG]

neat

[@Lemosoffroad]

What if you’re.005 in the hole and you have a.06 gasket is that enough clearance

[@BustedWalletGarage]

In pro-stock, did Steve ever use beryllium pistons ? How good are they ? Do teams still sneak them into the engines ?

[@RadDadisRad]

Steve tech is the best tech

[@icyflametv418]

THE HEADGASKET GAVE HIM THE EXTRA CLEARANCE FOR THE VALVE NOT TO HIT THE PISTON

[@jameslahee9874]

-017 or 018. Clearance Chevy I have a rectangle 188 219cc 017 thousants

[@barryobler9491]

Steve, over the years I have checked valve to piston with either clay or dial indicator. Have I missed a video showing how you personally check it, or will there be one upcoming?

[@stevemorrisracing]

Not yet

[@racerdoc]

Where in the rotation do you check the intake valve clearance? Is it between a certain degree range or just around 10 ATDC?

[@robertprice2108]

Would it not be determined by the specs of the cam?

[@stevemorrisracing]

the normal closest point is 10 ATDC but you can move it around a degree at a time to find the closest in your application.

[@robertprice2108]

@@stevemorrisracing thanks Steve for sharing an when I bought a cam off an engine builder 1 time he said for me to set it up on 12.5° on intake valve before tdc and vp was 70tho of inch on BBC and dont remember what it was set straight up. I think it ended up being 3° advanced. Im just curious an never mine learning so when you move the cam around it will change the vp correct and I guess it would determine how much it is moved to how vp it would have right? So what I'm ask is you would still check it at 10 ATDC ?

[@TheProchargedmopar]

👍

[@beachboardfan9544]

7:30 Hysteresis

[@mccanlessdesign]

"ClearAnce"

[@stevemorrisracing]

LOL

[@mccanlessdesign]

@@stevemorrisracing Love the detail, man - thanks a million!

[@faststang85]

I know this is a old video but would this apply for a street engine as well? I'd imagine different piston materials will grow different amounts?

[@bigredracer7848]

69👍's up Steve M thanks again for taking us all to school