Valve Float! What Is It, And How To Avoid It | Engine Masters | MotorTrend

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  • เผยแพร่เมื่อ 24 ก.ค. 2022
  • We all know valve float as the evil that lurks beyond the redline, the dreaded robber of horsepower and destroyer of valves. But what is it really? What does it look like when it happens? And how can you put it as high in the RPM band as possible?
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ความคิดเห็น • 281

  • @cornelius6304
    @cornelius6304 2 ปีที่แล้ว +121

    Downshifting to 1st at 100mph might cause some float.. among other things.

    • @shifter8207
      @shifter8207 2 ปีที่แล้ว +6

      Or missing a shift

    • @brysonshires9742
      @brysonshires9742 2 ปีที่แล้ว +5

      2nd or 3rd at 100 would destroy everything

    • @speedyme200
      @speedyme200 2 ปีที่แล้ว +4

      Money shift

    • @PSNxFTWxRAGOI
      @PSNxFTWxRAGOI 2 ปีที่แล้ว +9

      More rpm more hp

    • @skylerpratt2306
      @skylerpratt2306 2 ปีที่แล้ว

      Otherwise known as money shifting as stated already

  • @blownvnv6637
    @blownvnv6637 2 ปีที่แล้ว +48

    Valve float, valve bounce or valve lofting are all different things and can have different causes, including spring pressure, harmonics and cam lobe design. There is a great video on youtube taken with a high speed camera under the rocker cover and shows valve bounce which is what I believe we are talking about in this video.

    • @chrismechanic2000
      @chrismechanic2000 ปีที่แล้ว +1

      that vid you are talking about is one of the coolest vids on you tube for engineers.

    • @hillbillymotorsportz8514
      @hillbillymotorsportz8514 ปีที่แล้ว +2

      Post a link to that video I'm sure I'm not the only one who wants to see it

  • @JETZcorp
    @JETZcorp ปีที่แล้ว +10

    Ahh, valve float. One of my favorite things about 2-strokes and rotaries is the sheer "who cares" factor with rpm. It's a neat experience to feel the power nose over, and then hold it wide open for two minutes, knowing that it's just resonance timing and the engine has 4,000 more rpm of mechanical overhead. Just... make sure you have good premix that day, lol.

  • @lessmith1409
    @lessmith1409 2 ปีที่แล้ว +6

    The person i bought my 67 el camino from had a auto shut off on the ZL1 engine. It had trick heads, had roller rocker arms, triple valve springs and steel retainers. Victor jr manifold, 750 holley carb. Solid lifter cam 500" lift + 260° duration. 4.56 posi rar 1 ton axles and 4 speed. Lots of fun.

  • @carlob517
    @carlob517 2 ปีที่แล้ว +10

    quite some years ago i had an Alfasud which has a flat 4 overhead cam per bank motor boxer motor just like a Subaru, it could rev to well over 8,000 rpm as it only had a 54mm stroke , one day i experienced valve float at around 6150rpm no misfiring just a strange sensation while reving , i didn't know it was valve float at the time , a friend of mine who worked at an Alfa dealer told me what the problem was he said that probably some retainers had split causing a loss of spring tension on the valves he said because of the flat 4 design the pistons were closing the valves affected ! , luckily there was no damage to the pistons or valves i could see once i had the heads removed Phew close call , he overhauled the heads and found that 2 valve retainers had cracked/split in the cone part of the retainer where the valve stem collets are seated causing a loss of valve spring tension , i fully understand why spring tension on a Valve is important as your video has pointed out cheers

  • @Trucker_Dashcam
    @Trucker_Dashcam 2 ปีที่แล้ว +34

    No titanium valve? I guess I missed the valve choice discussion. Mushrooming stems or what?

    • @MrRandy3504
      @MrRandy3504 2 ปีที่แล้ว +4

      Think i missed something as well

    • @6226superhurricane
      @6226superhurricane ปีที่แล้ว +1

      rapid wear constant adjustment. no good for a street engine.

    • @daddyschainsjewelry
      @daddyschainsjewelry ปีที่แล้ว +3

      And 100 bucks a valve vs 12

    • @25aspooner
      @25aspooner ปีที่แล้ว +1

      Bronze valve guides, dlc or nitride coated stems to not gall, and sometimes special lash caps to keep the roller from eating the top if the stem. And price… Always the price.

  • @shammon1
    @shammon1 4 หลายเดือนก่อน

    What a remarkable clip. Thanks for explaining this issue great!

  • @maxreed5555
    @maxreed5555 ปีที่แล้ว +4

    My dad had an 83’ CJ7 with the inline 6 and it used to float the valves going up hills, had over 300k miles on it too

  • @davebaker9128
    @davebaker9128 2 ปีที่แล้ว +6

    I have a panhead harley that I've owned for over 40 years, am running a ridiculous big cam, and use the stock FL valve springs (way to light seat pressure for the cam) and I rely on the valves floating as a rev limiter, but having it for as long as I have, I don't abuse it, also the light pressure on the valve train has the benefit of not wearing stuff out fast, I do weird things with my vehicles but would never do on a customer's bike, car whatever, but for myself I go way out in left field, and it works for me

  • @rydahj5054
    @rydahj5054 ปีที่แล้ว

    Such a great basic video thank you for this 🙏🏻

  • @robertyoung8289
    @robertyoung8289 2 ปีที่แล้ว

    So informative. Thank you.

  • @Ianslabratory
    @Ianslabratory ปีที่แล้ว

    Thank you for all of your knowledge

  • @frfrpr
    @frfrpr 2 ปีที่แล้ว

    Great show. Thanks

  • @fsj197811
    @fsj197811 ปีที่แล้ว

    Nice, thanks for sharing!

  • @hofthomecrap9534
    @hofthomecrap9534 2 ปีที่แล้ว +1

    Very informative!

  • @FSHSKainon
    @FSHSKainon 2 ปีที่แล้ว +6

    Engine Masters PRO Sessions 🙂thanks Guys!!

  • @redtailhawk289
    @redtailhawk289 ปีที่แล้ว

    Eng Masters is the best car show , Tell use about the intakes on the shelves behind you. Thanks

  • @edengates66
    @edengates66 2 ปีที่แล้ว +1

    Thank you techno hippies I learned a lot

  • @DeliveryMcGee
    @DeliveryMcGee 2 ปีที่แล้ว +25

    Preventing valve float is also why Ducati motorcycle engines sound like, as one person put it, "a Cuisinart full of clarinets" -- actually looking at the system as implemented breaks my brain with the linkages involved, but short version, the top end works kinda like the bottom-end rotating mass -- the valve stems are pushed /and/ pulled by the cam, no springs, so no float, but it's very noisy and probably a bit harsh on parts without the tolerance buffer that a spring provides. But when you need a twin to make twice the revs of the tested V8, and thus fire each cylinder ... not gonna lie, but I must've slept through the session of physics class covering the square-cube law. A 1.3L twin is working a lot harder per cylinder to bet to 12kRPM than a 5L V8 at 6k, that's just basic math, right?

    • @goratgo1970
      @goratgo1970 2 ปีที่แล้ว

      Still amazed at Formula 1 engines.

    • @rhubarbpie2027
      @rhubarbpie2027 2 ปีที่แล้ว +4

      Ye Olde Desmodronic systeme

    • @taylorsrus9543
      @taylorsrus9543 2 ปีที่แล้ว +1

      But they still dont make power so kinda pointless. If it wasnt for favorable rules you would never see another one on a racetrack

    • @ryanwalker9472
      @ryanwalker9472 2 ปีที่แล้ว +1

      I learned the hard way about desmo service. Lol

    • @DeliveryMcGee
      @DeliveryMcGee 2 ปีที่แล้ว +1

      @@ryanwalker9472 I pity the man (apparently you) who had to work in that ridiculousness.

  • @cuckleberryfinn4618
    @cuckleberryfinn4618 2 ปีที่แล้ว +5

    Floating a valve is my biggest fear in my old Chevy. I’ve got a 1978 Big 10 with the 454 and 400 turbo trans. It’s all original parts, and at 128k lol

    • @taylorsrus9543
      @taylorsrus9543 2 ปีที่แล้ว

      Probably fine with that 400 lift cam and a redline of something in the 4000rpm range

    • @cuckleberryfinn4618
      @cuckleberryfinn4618 2 ปีที่แล้ว +3

      @@taylorsrus9543 if I put a cam in it I might see 4000 rpm but it doesn’t care for more than 3500 lol

    • @racecitypatriot66
      @racecitypatriot66 ปีที่แล้ว

      Be ok long as you don't hold down while they float

    • @AB-80X
      @AB-80X ปีที่แล้ว

      I'd be more concerned about how the locks and retainers are doing at that age.

  • @1SlimeyFukR
    @1SlimeyFukR 2 ปีที่แล้ว +9

    Boy you were made for the camera!Always interesting listening to you David,
    Thank you for the awesome content

  • @jdsstegman
    @jdsstegman 2 ปีที่แล้ว +2

    You boys need to play around with the same concept but on a modern overhead cam engine.

    • @goratgo1970
      @goratgo1970 2 ปีที่แล้ว

      Sure, to see the benefit of design but doesn't demonstrate the issue with pushrod engines.
      Try out the ultimate, Formula 1 pneumatic valvetrain!

  • @tedjones450
    @tedjones450 2 ปีที่แล้ว +7

    Valve float is also a function of the spring harmonics, should have talked about BeeHive springs. Beehive springs have less of an issue with harmonics and you are able to use less spring pressure to control the valvetrain

    • @goratgo1970
      @goratgo1970 2 ปีที่แล้ว +1

      And for certain engines like Buick, they clear the top at the rocker better.

    • @davidgalea6113
      @davidgalea6113 2 ปีที่แล้ว +1

      if beehives are better why do the nascar guys never use them?

    • @crd-nz_001
      @crd-nz_001 2 ปีที่แล้ว +1

      @@davidgalea6113 its the difference between "loft" and "float".
      The idea was to ski jump the valve off the nose and have it catch on the slope. Beehives provide more stability, but loss power because they dont promote the ski jump.
      Mind you, this can be done with a solid flat tappet. Try this with a roller cam (especially a needle roller) and the roller destroyes itself from being unable to take the landing impact...

    • @davidgalea6113
      @davidgalea6113 2 ปีที่แล้ว +1

      @@crd-nz_001 they used flat tappets in the cup engines and they used rollers in the nationwide engines.. today both series use roller lifters.. my point was that you rarely see the beehive springs on high rmp engines...usually it is the double/ triple springs. probably not the best option if you are going above 8000...

    • @tahcogunworks
      @tahcogunworks 2 ปีที่แล้ว

      @@davidgalea6113 hard to get enough pressure as no room for multiple springs.

  • @flinch622
    @flinch622 10 หลายเดือนก่อน

    "boing" Absolutely perfect.

  • @grndragon2443
    @grndragon2443 ปีที่แล้ว

    You guys need to do a Free Valve conversion.

  • @robertaBooey69
    @robertaBooey69 2 ปีที่แล้ว +1

    Only if Grateful Dead was still around these guys would totally fit in

  • @mohamadsuleimankhamis4627
    @mohamadsuleimankhamis4627 ปีที่แล้ว

    Nice

  • @claycopopo
    @claycopopo 2 ปีที่แล้ว +3

    Why no Ti valves? No explanation for why this is bad?

  • @brianf8621
    @brianf8621 ปีที่แล้ว +2

    Why did he state don’t use Titanium values?
    I missed that part.
    Always great information in the show.

    • @jamesmedina2062
      @jamesmedina2062 9 หลายเดือนก่อน

      me too!

    • @stevechaffee2360
      @stevechaffee2360 5 หลายเดือนก่อน

      Yeah! Maybe it's a reference to the ls7 valve drop issue?

  • @offgridnzdotcom1027
    @offgridnzdotcom1027 2 ปีที่แล้ว

    first time i learned about it was in a r32 in the back seat watching it bounce at 8 was also hauling on a back road

  • @demolitionman9307
    @demolitionman9307 2 ปีที่แล้ว +7

    Us Australians call it, "valve Bounce" a harmonic inbalance, be amazing to see it in ultra slow motion. Hint hint. Lol here's a great video idea, a sectioned cylinder head, where vales are exposed. Then test them at high RPM's, using a slow motion camera, hint hint you can thank me later loolz

    • @jamesmedina2062
      @jamesmedina2062 9 หลายเดือนก่อน

      I agree with what you said about not buying Chinese junk. But I say buy Aussie, Canadian or US goods and then Taiwanese is decent especially for certain things.

  • @edwardwood3622
    @edwardwood3622 2 ปีที่แล้ว +2

    2 things; why did the engine not make more power when it was flowing more air and it was lame to throw the Ti comment in with no explanation.

  • @jfreake13
    @jfreake13 2 ปีที่แล้ว +3

    If Dulcich had blonde hair he would look like Dave Mustaine lol

    • @JakeSanMartin
      @JakeSanMartin ปีที่แล้ว

      I was gonna write that same comment haha.

  • @robertclymer6948
    @robertclymer6948 2 ปีที่แล้ว

    Great Info guys. David, are you going to go back to long hair too? Love to see you sport a mullet! Thanks for sharing and Cheers from Motown/Dearborn.

  • @michaelgiglio1571
    @michaelgiglio1571 ปีที่แล้ว

    Is their a lighter spring with a faster return rate, like maybe do away with the damper or thinner outer and heavier inner. I remember some of the old Isky,s worked well and smoothed out like it didn't rob power. Just a thought. Mike

  • @andretorben2813
    @andretorben2813 2 ปีที่แล้ว +1

    Freiburger, you need to get one of those caps that has long hair attached to it, just so you fit in with the other guys.

  • @boostedthirdgenracing
    @boostedthirdgenracing 8 หลายเดือนก่อน

    Do you need more valve, spring pressure when under boost?

  • @Looking4TravelingWelderJob
    @Looking4TravelingWelderJob 2 ปีที่แล้ว

    Now do one for us on valve adjustment

  • @r000tbeer
    @r000tbeer 2 ปีที่แล้ว +3

  • @wreckerjonny6144
    @wreckerjonny6144 2 ปีที่แล้ว +2

    Valve float shift light with out the light.

    • @AB-80X
      @AB-80X ปีที่แล้ว

      It's great. Not blinding you at night.

  • @daesmith3274
    @daesmith3274 2 ปีที่แล้ว +1

    Funny what you get away with when young. I used to know my 81 f150 with a BBF would pull a mud pit in a higher gear was it wouldn't rev any higher in gear then neutral lol.

  • @sveinuuung
    @sveinuuung 5 หลายเดือนก่อน

    Your conclusion was:(among other things) ...-and don't use a titanium valve. Why?Longevity? How about titanium retainers? Otherwise, a great channel!

  • @brettmccafferty465
    @brettmccafferty465 2 ปีที่แล้ว +3

    Why not run a titanium valve?

    • @Scalihoo
      @Scalihoo 2 ปีที่แล้ว +2

      For race motors yes

  • @WholesaleTurbos
    @WholesaleTurbos ปีที่แล้ว

    Got it, now if I can find a place that sells upgrades for my rotary
    🐸

  • @Rickgrott100
    @Rickgrott100 2 ปีที่แล้ว

    Crazy a guy teaching class about valve float LOL

  • @johnbujalski8602
    @johnbujalski8602 2 ปีที่แล้ว +8

    Why no Ti valves? They are fantastic at high rpm and allow for more aggressive cam profiles. The other I would like to see are Sodium filled valves for higher cylinder pressures.

    • @makantahi3731
      @makantahi3731 2 ปีที่แล้ว +1

      maybe because fatigue

    • @AB-80X
      @AB-80X ปีที่แล้ว +2

      Sodium filled valves? Not in my engine please.
      There's a reason why you don't see them any more, and there's a reason why they are never used in racing. High cylinder pressure? What does that have to do with sodium filled valves? I'd take either Inconel or Ti for that application.

    • @jamesmedina2062
      @jamesmedina2062 9 หลายเดือนก่อน

      sodium is for boosted applications not for revving

  • @patriklindstrom1992
    @patriklindstrom1992 ปีที่แล้ว +1

    Desmodromic valvetrain is the only way to totally eliminate any valve float.

  • @HairBandDan
    @HairBandDan ปีที่แล้ว

    Can this be tested on a chassis dyno?

  • @crabapple1974
    @crabapple1974 2 ปีที่แล้ว +1

    That background music! Sounds like a guy is going to ring the door asking to clean the pipes. It is also TOO LOUD!

  • @jzxtrd337
    @jzxtrd337 2 ปีที่แล้ว +2

    Valve bounce, what is it? The old school rev limiter 🤣

  • @kalan4787
    @kalan4787 2 ปีที่แล้ว

    This is an old episode at this point. When does the next episode drop on MotorTrend+?!?! I'm feening. I have an idea for an episode: "426 Hemi vs 427 Chevy vs 427 Cammer. Which wins Daytona?"

  • @tvdroid22
    @tvdroid22 ปีที่แล้ว +1

    You mentioned all the new LS engines use beehive springs, but credit where credit is due...Mopar used them in all their Magnum engines starting in 1992.

    • @AB-80X
      @AB-80X ปีที่แล้ว

      And Mercedes in 1954. What's your point?

    • @thebigpicture2032
      @thebigpicture2032 ปีที่แล้ว

      The technology comes from military aircraft engines developed in the early 1900’s.

    • @tvdroid22
      @tvdroid22 ปีที่แล้ว +1

      @@thebigpicture2032 My comment was not to discuss the origins of the design. The commentary would seem to imply the LS, and GM in particular, was breaking new ground by using the design, when the first large scale application would seem to be the Magnum series.

  • @sherryhofstetter8518
    @sherryhofstetter8518 2 ปีที่แล้ว

    I wish they had a heart with the 👍👎... great video, thanks for the info. You guys are the best.👍👍👍

  • @JerryDLTN
    @JerryDLTN 2 ปีที่แล้ว

    Can you test Koenigsegg's Free Valve (no-spring) heads on that engine?

  • @3madeamps
    @3madeamps ปีที่แล้ว +1

    try rhoads lifters

  • @jordanlip112
    @jordanlip112 2 ปีที่แล้ว +1

    I've got enough valve float to unsink the Titanic

  • @paulhotson5820
    @paulhotson5820 2 ปีที่แล้ว

    Most change rockers for more valve lift not for weight.

  • @SuperOperator4
    @SuperOperator4 2 ปีที่แล้ว +3

    So what would be the rotational speed of the cam in relation to the crank? Are they the same?

    • @SuperSecretSquirell
      @SuperSecretSquirell 2 ปีที่แล้ว +4

      In a 4-stroke engine it's always half of crankshaft speed.

    • @speedyme200
      @speedyme200 2 ปีที่แล้ว +1

      1:2 ratio

    • @AB-80X
      @AB-80X ปีที่แล้ว

      He literally starts out by saying this. Have you ever worked on an engine?

  • @rogermason5833
    @rogermason5833 2 ปีที่แล้ว +6

    Ok, you added spring stiffness to resolve this particular engine's valve float problem: so what is the limiting factor to adding even more spring stiffness and running to higher RPM's?

    • @fish_R_stinky69
      @fish_R_stinky69 2 ปีที่แล้ว +4

      Or making it DOHC.

    • @reesewilliamson3346
      @reesewilliamson3346 2 ปีที่แล้ว +8

      If the valve springs are too stiff, the rockers and push rods will self destruc because they are working too hard. What's the limit on RPM? It's a big block Chevy, you spin it any faster than 5500 the pan gets full of piston skirts REAL quick.

    • @SoI_Badguy
      @SoI_Badguy 2 ปีที่แล้ว +7

      Heavy valvesprings rob power

    • @goratgo1970
      @goratgo1970 2 ปีที่แล้ว +1

      @@reesewilliamson3346 Also switch to solid lifters if want life at higher RPM's.
      For a daily, just build for low to mid to avoid a grenade.

    • @fish_R_stinky69
      @fish_R_stinky69 2 ปีที่แล้ว +1

      @@SoI_Badguy I thought they prevent floating?

  • @dietervaloczky6051
    @dietervaloczky6051 2 ปีที่แล้ว +1

    I ran comp 911 springs in my 5400 rpm 454 and at 5550 they floated, I put in pac hotrods springs and no float, still singles but oval wire with a flat tappet X268 comp cam

    • @KingJT80
      @KingJT80 ปีที่แล้ว

      comp xe cams are more modern flat tappet cams. they need a pretty decent spring. 911s are lightweight vs what they really call for.

    • @jamesmedina2062
      @jamesmedina2062 9 หลายเดือนก่อน

      never heard of oval wire springs. where do you find them?

  • @richb.4374
    @richb.4374 2 ปีที่แล้ว

    I wonder if anyone has tried a system for opening and closing valves that uses heavy duty electronic solenoids/actuators that can be controlled by a computer module similar to an engine ECU? I remember the crappy Cadillac 8-6-4 disaster, but that is not exactly the same as what I'm talking about. With electronically controlled valves, you wouldn't need a camshaft, lifters or pushrods, hence no valvetrain rpm limit, just a bottom end rpm limit. You could literally change lift and duration on the fly and never worry about valve float. Less moving parts, less weight, it would be interesting to see someone try it if it already hasn't been done.

    • @z0n4l1
      @z0n4l1 ปีที่แล้ว

      könidsegg has freevalve system witch is basically what you are saying it has not been ina a car alrdy but is going into the gemera with a 600hp 3cyl

  • @matthewrich7673
    @matthewrich7673 2 ปีที่แล้ว

    Valve float with a roller cam can destroy roller lifters especially on a solid roller.

  • @ryanwalker9472
    @ryanwalker9472 2 ปีที่แล้ว +1

    Desmo valves in a chevy

  • @yarrdayarrdayarrda
    @yarrdayarrdayarrda 2 ปีที่แล้ว

    I've dyno'd where the graph dropped at about a 70 degree angle. Interestingly enough, a .060" valve shim fixed it.

    • @goratgo1970
      @goratgo1970 2 ปีที่แล้ว

      Spring shim?

    • @AB-80X
      @AB-80X ปีที่แล้ว

      Reason is that you had too much free spring when compressed. Obviously it will also increase pressure, but what few seem to think about is how a spring that is too tall affects control even if the pressure is correct. Never let it be more than 0.070 between bind and open height. About 0.030-0.040 is what you want and that's a big part of why so many have issues. Probably one of the most overlooked issues in valvetrain setups.

    • @AB-80X
      @AB-80X ปีที่แล้ว

      @@goratgo1970 Guess so.

  • @nyftn
    @nyftn 2 ปีที่แล้ว

    just like max piston speed . there's a maximum valve speed for every setup . even the ducati system has a limit .

  • @ashtonmariefranklin725
    @ashtonmariefranklin725 2 ปีที่แล้ว

    I Like to know What would happen if you had too stiff of a valve spring.

    • @CrusherGarage
      @CrusherGarage ปีที่แล้ว

      I think it might wipe out the cam. Or break a lifter depending on the setup...

    • @AB-80X
      @AB-80X ปีที่แล้ว

      It really depends on the specific situation.
      Sometimes you will just be down on power and wear out things slightly faster. Sometimes almost nothing. Other times you might break rocker studs, bend pushrods, wear out valve stem heads, tulip valves, crack seats, collapse lifers, destroy lifter rollers, etc. etc. etc.
      It depends...

  • @Greasyoldmopars
    @Greasyoldmopars 2 ปีที่แล้ว +2

    Hehe I keep them valves floating daily ,😂 stock 302 lives at 8grand

  • @CallofDoobie585
    @CallofDoobie585 ปีที่แล้ว

    Did dulcich get new jibs or something??? Looks a lil different

  • @scrotiemcboogerballs1981
    @scrotiemcboogerballs1981 2 ปีที่แล้ว

    If you don’t want to float take off your water wings lmao jk thanks for sharing buddy great video

  • @sweetness34km
    @sweetness34km 11 หลายเดือนก่อน

    My small block 600+ hp 480 torque still pulls at 8200 i keep it at 7200 most mostly 65 6800. However its built rigjt

  • @ShovelMonkey
    @ShovelMonkey ปีที่แล้ว

    With my 4.10 gearing I really wanted to plan my build very carefully. Overkill? You bet. Expensive? Oh yeah. This build lightened my wallet, which encouraged me to eat less and lighten myself. Next up, the car (68 Barracuda fastback) gets a diet to bring her down to 2,900-3,000 lbs. with me in it.
    Valve float? Not in my little 3.580" stroke Chrysler 360LA motor. I have a mild Lunati Voodoo *solid* flat tappet cam, 80 gram lifters, I did add mass to the valve train with some GOOD pushrods because the Mopar LA series cams sit kinda high and well, the geometry could be better. Comp 7228 438 lbs/inch conical valve springs, tool steel retainers, ductile iron rockers, Ferrea hollow stem intake valves. No, I am not running sodium filled exhaust valves, I want to keep the heat in the combustion chamber where it belongs rather than in the oil which would be absorbing that heat through the valve stems as the oil (Royal Purple HPS 10w30) lubricates and cools them. The plus side for that would be any water in the oil system would be boiled off rather quickly.
    You couldn't *pay* me to build a motor with hydraulic roller lifters, and solid rollers are for the track.

  • @chrissanders2562
    @chrissanders2562 ปีที่แล้ว

    I have a 1984 Lincoln town car thats got CFI. Anything past half throttle makes no difference its like i only have less than half a pedal. Tried literally everything. Whats your thoughts?

    • @KingJT80
      @KingJT80 ปีที่แล้ว

      probably where the fuel cutoff is at. what RPM is it happening at? they design stuff from the factory so you cant blow it up like that trying to rev it to the moon

    • @chrissanders2562
      @chrissanders2562 ปีที่แล้ว

      @@KingJT80 its not really at a specific rpm its just in general past half throttle really makes no difference than half throttle. Itle rev to the moon in park its more of a lack of throttle response. Ive done everything i can think of. New injectors new tps new distributor everything. New iat new ect plugs wires the works.

  • @grahammboyett3172
    @grahammboyett3172 2 ปีที่แล้ว +4

    You'll hear a engine float valves. Not a good thing. I have a camshaft that's runs up to 5500 rpm. But I still maintain the single hd springs. So yes weight is a problem. My engine will clatter at 6500rpm. Don't hurt the engine to go to 6000. Just point less on a street engine. I could have double springs. But having a soild camshaft. It will wear it down quicker with double springs. So I normally only hit 5000 in first and 5500, in the remaining gears.

    • @taylorsrus9543
      @taylorsrus9543 2 ปีที่แล้ว +1

      Is it a diesel?

    • @grahammboyett3172
      @grahammboyett3172 2 ปีที่แล้ว

      @@taylorsrus9543 no it's not a diesel.

    • @jradish
      @jradish 2 ปีที่แล้ว

      @@taylorsrus9543 a diesel would have holes in the block before 4500

    • @taylorsrus9543
      @taylorsrus9543 2 ปีที่แล้ว

      @@jradish I better go look for mine.

    • @kylebeach2316
      @kylebeach2316 ปีที่แล้ว +1

      @@jradish a high performance diesel engine can rev well past 4500 rpms but a stock diesel engine will certainly grenade itself

  • @stanleyhall6102
    @stanleyhall6102 2 ปีที่แล้ว

    But what do I now maybe 🤔 the crypt keeper mullet is in ..

  • @Oldbutter
    @Oldbutter 2 ปีที่แล้ว +2

    Whats wrong with titanium valves ?

    • @AB-80X
      @AB-80X ปีที่แล้ว

      Nothing. Each thing has its place.

  • @856Dropout
    @856Dropout 2 ปีที่แล้ว +1

    Got to cut your hair Steve. Looking like the Crypt keeper.

  • @einstein3509
    @einstein3509 ปีที่แล้ว

    I have a question.
    Why would my engine builder use 1.6 rockers on the intake and 1.5 on the exhaust?
    I can run 1.6 on all of them if I want to.
    I’m just not sure why he did what he did.
    He’s a hard guy to get ahold of or I would ask him.
    He built me a 383 stroker running “according to his Dyno” 500hp 520tq
    Cam 234/242
    Intake cam lobe 374 with 1.6 rocker = 598 lift
    Exhaust cam lobe 382 with 1.5 rocker = 573 lift
    The heads have 205 intake 160 exhaust valve.
    Using a comp roller cam and comp short travel hydraulic lifters.
    According to Comp the springs he used are to weak and that why my valves a floating at above 5800rmps
    So I’m planning on installing the right springs and a stud girdle and installing those ultra pro magnum roller rockers.
    Just not sure if I should change that set up from 1.6/1.5 to 1.6/1.6
    Oh and the heads “according to Brodix” are good for a 640 lift.
    Any explanation for that set up?

    • @kevinbender1754
      @kevinbender1754 2 หลายเดือนก่อน

      i know this is an old video. but your cam spec math is not accurate. if i figured my cam like that it would be 1135 lift. your measurement is from the cam base to top of lobe. the equation is gross lift minus lift from centerline of cam to top of lobe and then multiplied by rocker ratio.

  • @waysasunder2434
    @waysasunder2434 2 ปีที่แล้ว

    Is this still common with a Dohc type motor?

    • @AB-80X
      @AB-80X ปีที่แล้ว

      Yes.

  • @einstein3509
    @einstein3509 ปีที่แล้ว

    Do you guys have an email address I can use?
    I’m having a RPM issue that I can’t resolve.
    New engine build all roller and I can’t power past 5800rpm.
    After 6000rpms the engine makes this horrible cackling noise and just loses power AFR goes rich.
    Built to handle 7000 rpm expecting 6500.
    I’m guessing valve float but could it be an ignition distributor issue?
    I’m using an MSD ready to run distributor.

  • @freedomfighter1000
    @freedomfighter1000 2 ปีที่แล้ว +1

    WHOA WAIT, why not a titainium valve?????

    • @AB-80X
      @AB-80X ปีที่แล้ว

      They are not suitable for street applications. You can read up on why in many places.

  • @tylerseitz6337
    @tylerseitz6337 2 ปีที่แล้ว

    Have you guys ever tried a springless valvetrain before? What has to happen to the engine in order to do that?

    • @wildcat6669
      @wildcat6669 2 ปีที่แล้ว +1

      It's called Desmodronic Ducati is the only company to use it

    • @bigblockjalopy
      @bigblockjalopy ปีที่แล้ว +1

      Even that needs springs, but yes, it can't float.

  • @joe-hp4nk
    @joe-hp4nk ปีที่แล้ว +1

    Why would you not run a titanium valve?

    • @AB-80X
      @AB-80X ปีที่แล้ว

      Great for racing, but wears too fast for the street in many cases.

  • @WarriorOfEden3033
    @WarriorOfEden3033 ปีที่แล้ว

    Explain it with OHC

  • @bobvalentine8927
    @bobvalentine8927 ปีที่แล้ว

    Solid lifters and good springs is the way to go

  • @kraigvanderwyk1153
    @kraigvanderwyk1153 ปีที่แล้ว

    Aren’t the steel rocker actually lighter. Stronger therefore less material.? At least this is what comp ultra pro magnum claims

  • @dgholstein
    @dgholstein 2 ปีที่แล้ว +5

    I'd like to hear their take on dual overhead cam, where we get rid of the pushrod completely AND use smaller/lighter valves. More flow and revs and better reliability?

    • @StevenAndrews
      @StevenAndrews 2 ปีที่แล้ว +4

      you still need spring to control the valve return. dohc gets rid of a lot of mass' inertia you have to overcome. you want valve control though, look at f1 pneumatic...no spring weight to overcome. similar with freevalve.

    • @C_Castillo
      @C_Castillo 2 ปีที่แล้ว +1

      Pneumatic valves literally negate these problems, these guys need to make a 1500HP 1.5L 4 cylinder, that can operate at 75k rpm

    • @dgholstein
      @dgholstein 2 ปีที่แล้ว +1

      @@C_Castillo But there's the complexity and reliability versus power-gains consideration, same as DOHC.

    • @C_Castillo
      @C_Castillo 2 ปีที่แล้ว +2

      @@dgholstein these guys have literally been trying to make more power, in the 80s 1.5L 4cylinder engines were dumping out 1500HP, they have no excuse , they’ve blown up engines for a lot less, they just need to make a 75k RPM monster or something that tops at least 1k HP theyre so called “engine masters” they should be able to do it easily.

    • @fish_R_stinky69
      @fish_R_stinky69 2 ปีที่แล้ว +1

      @@C_Castillo 75k?

  • @jb3161
    @jb3161 2 ปีที่แล้ว

    thats what finnigan uses instead of using a shift light

  • @xxxxrock32xxxx
    @xxxxrock32xxxx 2 ปีที่แล้ว +1

    Mr. D I respect your knowledge and work ethic plus you're a Mopar guy. But dude clean up your act.

  • @peterrobins3708
    @peterrobins3708 2 ปีที่แล้ว

    Dear EngineMasters/MotorTrend, how do Australian fans legally access Engine Masters, Roadkill, Dirt Everyday etc as we're GeoBlocked. Are there any streaming platforms we can use to view without breaking to law?
    Thanks

    • @whammy860
      @whammy860 2 ปีที่แล้ว +1

      Engine masters is Amazon, pretty sure the motor trend channel is on there

    • @hot308vb
      @hot308vb 2 ปีที่แล้ว +1

      I pay my Mt with google pay and can watch it with a VPN... but I know others can't even have a Mt account cos of ozy credit cards etc etc

    • @peterrobins3708
      @peterrobins3708 2 ปีที่แล้ว

      @@hot308vb That's where I'm at and Paypal is very odd, join, got account frozen, then after appeals it was unfrozen, 40 bucks went out but hadn't bought anything...hoping for the legal option 🙂

  • @williepelzer384
    @williepelzer384 2 ปีที่แล้ว

    As my mom used to say in 1970 to many RPM'S.

  • @calvincooley1074
    @calvincooley1074 2 ปีที่แล้ว

    Losing control of your bowels is way cheaper but you have more fun achieving valve float, lol so to speak!

  • @toadamine
    @toadamine ปีที่แล้ว

    Also bent pushrods!

  • @james10739
    @james10739 ปีที่แล้ว

    So a cam with 360° of duration is not good

  • @ryurc3033
    @ryurc3033 2 ปีที่แล้ว

    I go back to a video I watched on a TH-cam channel complete toilet garage, 350vs LS.... LS motor chained up to a cherry picker, Had it held on limiter with no water in it for something like 7 minutes.....like laughing in the face of valve float,

  • @mattcangie
    @mattcangie 2 ปีที่แล้ว +1

    I love these shows! Regardless of these guys turning into long-haired, hippies; they're old school GENIUSES I can trust to give me the facts I need/want to know(before blowing up my engine)

  • @frankceney942
    @frankceney942 2 ปีที่แล้ว

    My motto is when the valves float shift

  • @tjsingh5163
    @tjsingh5163 2 ปีที่แล้ว

    Brûlée is starting to look a little like Freak-show from Harold & Kumar

  • @notsure8041
    @notsure8041 2 ปีที่แล้ว

    Steve dulcich is starting to look like Fabio who's doing his makeup these days

  • @noahsmith9385
    @noahsmith9385 2 ปีที่แล้ว

    Can you have too much valve spring

    • @blubu68
      @blubu68 ปีที่แล้ว

      Yes, when using hydraulic lifers, they can only handle so much pressure. Different manufactures spec different pressures

  • @SurlyMike
    @SurlyMike 2 ปีที่แล้ว

    Haha yeah, valve float means time to shift. I'm down with that.