De-atomization in intake tract in IC racing engines PART 1

[@tunnelportterror]

intriguing stuff...who'd have thought a valve job would get that granular in detail, like watching a film...

[@tedjackson2603]

Thank you Darin, priceless experience shared here, much appreciated!

[@dbamf2300]

Some of the best content on the internet available. Thank you.

[@tomanypedos1153]

I have a set of CFE storm heads , I went and had a look at the seat and chamber. You are 100% right. It has a step at the chamber above the seat. I have had those heads for 7 years and never really noticed it. Unbelievable !

[@scottcolantuono9397]

Thank you Darin, for sharing your knowledge, great video!

[@wayneireland4802]

Thankyou mr Morgan for sharing your experience as I live in Australia and aspire to be half knowledgeable as you.peace

[@billshiff2060]

I have to take exception at 21:00 when you state 7.5 degrees is the max according to venturi design rules. That angle is ONLY referring to the DOWNstream side of a venturi. In your runners it is more like the UPstream side of a venturi where it is much more flexible. Actual venturis typically have a 19-24degree angle upstream since there is little danger of the flow breaking away. 24degrees limit is only there to ease the transition into the throat of the venturi. Runners are not venturis and run in a different environment. IF there IS a limit on runner converging angle, it is not due to venturi design rules but has to be something else. I think you are right about the radius, the bigger rad involves too much air around the entrance and the smaller rad focuses the pressure distribution more to the area above the entrance. The blue runner looks to be in a corner with a wall beside it and the pink one no walls beside it. That could change the pattern too.

[@davidgalea6113]

I find this stuff fascinating..like you said knowing it works is not enough you really need to know why.. feel free to go as far down the rabbit hole as you like and thank you for sharing your knowledge.

[@BOOT]

Asked a porter I know one time bout blending that chamber machine ridge, he told me not to bother BUT I noticed on his work that he did. So I just did my best to blend it & later confirmed what I suspected when finding a GM guy who did lots of testing said blend it

[@dee1089]

thank you for all your knowledge.. i want more.

[@paulrossi3891]

Thank you for helping me understand ( the why) in what little I know, !

[@autonomous_collective]

Thx for sharing, Darin....

[@DragBoss351Cleveland]

Looking good, always breaking it down for me @ Darin Morgan

[@garykarenmcgruther6386]

Thank you for doing this. I have been waiting for these. So much to learn.

[@NoferTrunions]

One major unmistakable observation when wet flow is gotten right is the ability of the engine to cold start without choke, or very little. It can be quite dramatic.

[@minibikeaction4266]

I am so happy you are explaining this tec, thank you.

[@jeffbonifield8981]

Thanks for the great information that most would never have access to. In future classes (videos) can you also tell us your thoughts on port injected EFI applications and how they differ from, or are similar to the flow characteristics of moving air as opposed to a fuel--air mixture? Thanks again for your time and expertise! Jeff

[@darinmorgan3520]

Everything applies with EFI as it does with carburetors except plenum volume. Plenum volume is not a tuning factor with EFI like it is with carburation.. A properly designed EFI system in an unlimited NA engine should be in the plenum right above the runner opening so your still dealing with the same de-atomization problems. Injector placement down at the flange is done for throttle response which drag racing engines dont need. Plus, when you lower injector placement down the runner it decreases charge density and inertia super charging and VE suffers!

[@jeffbonifield8981]

@@darinmorgan3520 Wow! Thank you. Very interesting. Thanks for taking the time to do this series!, Jeff

[@darinmorgan3520]

Since you brought it up, hell yes. Thats a great topic and a very important aspect of induction system design. Particle flow (fuel droplets) air carried by velocity change not just the velocity itself. Thats why we need a short side radius and why that radius is so damn important. This is one reason air speed management ( peak, mean change) is the primary goal of any induction system designer. I will get to work on it.

[@briantooleyracing3554]

Awesome stuff Darin!

[@darinmorgan3520]

coming from you that means a lot. Thank you

[@mohanperformance.enginerd.1308]

I just watched this again. Such a great video.

[@steveroehlk8799]

Awesome content as always. Thank you.

[@savagefabrication795]

Thank you for the awesome video.

[@rageracing6435]

Awesome information! Thank you!

[@Bbbbad724]

Kip Martin! I have parts on my car from him , Darin you are a genius.

[@roadrunner4404]

Greatness

[@1o1carolina53]

SUBSCRIBED from D VIZARD quench video

[@kizzerplowright]

nice stuff very detailed very informed.

[@manitoublack]

So glad I stumbled across this channel (yay for the youtube algorithm. it knows all.)

[@natew1731]

I definitely enjoy the videos, thanks for sharing the info.

[@CudaFishEStories]

Thanks for taking the time to make, and post these videos. Thanks for sharing you knowledge.

[@racerd9669]

2 words you said about 3/4 of the way explains why a engine runs, Pressure differential. Everything in a running depends on it.

[@promodracer2191]

Another fabulous video Darin. CJ

[@kennyrmurray]

Hey Darreni watched your videos a couple times and I also watched your conversations with Tim. Love it all!! I thought you were gonna make more videos? Are you ever gonna do a set of small block Chevy heads in a video? That would be really great!! I am about to do my old school Dart Pro1 215’s for my sbc 409. I just took the motor back out to change the pistons so I can install my F1R Pro Charger Thanks. If there’s any misspelling I don’t have my glasses on lol

[@Between2Turns]

How much might the carburetor offset have played into your dykem testing results? Did you run the radiuses in reverse placement to confirm your findings? Great content, I’ve learned a lot and it has peaked my interest in the subject.

[@user-id9ft8qv4x]

Thanks for video!

[@b.c4066]

Thank you sir, may we have more please!

[@Gin_des]

amazing. many thanks

[@ernestoloewen3253]

Awesome content tank you

[@Jeffery-yo4vk]

How about a video on the the science of air flow angle on Ice,s

[@Giftied]

great info darin, enjoy these vids. can't wait till you get to the exhaust side and its relationship with the intake....btw i thought you were working at Mast?

[@adeismu5110]

Yuk pasukan rat motosportnya mana Go on!

[@NoferTrunions]

I'm debating the following for a 96 Gen 2 Viper. Heads were done in 1999, 269 cfm @ .600 28in. I'd like to get the work on the heads evaluated. Maybe there are problems that can be fixed and who knows, maybe some "low hanging fruit" that could be harvested.

[@exploranator]

What about just tilting the carburetors so that, combined with straight ports and intake runners, the air makes NO turns on the way to hitting the intake valve opening area? Yes, I know you would have to have carbs properly made or modified to work properly though at an angle. But, imagine a world (movie trailer voice) with NO turns from top of carb to intake valve!

[@WarpedSpeed]

the older manifolds curved the runners so the fuel would not drop out. did it work? I don't know. That was the days of carburetors, now fuel injection it is not an issure

[@approachingtarget.4503]

Dang...you are using dyes to mark the air flow. I thought i was the only one to do that.

[@Baard2000]

Oz Anderson , from Quadrant Scientific , also told me to do so...22 years ago...

[@Baard2000]

Saying this about valve jobs 25 years ..... And still customers saying : your seat jobs are more expensive..... yeah right.....

[@darinmorgan3520]

Cheap valve jobs DESTROY cylinder heads!

[@turbodudehere]

Thank you Darin, how far from Detroit will the classes be and how much will it cost.

[@darinmorgan3520]

They will be held at BES racing engines, Please email [e-mail] for information.

[@rivernorcal679]

Hey do you have time to check out our patent on the atomization valve? Its about 80 grooves cut in the radius of the intake valves. Would really appreciate your feedback as we are still manufacturing on a small scale. Up to 1/5 better mileage and emissions reduction by 27 percent tested on SBC's

[@darinmorgan3520]

I have seen and tested wings, ridges, blades, dimples, swirls and yes, grooves as your patent lays out. I do not doubt the increase in inefficiency as you have stated but in high speed racing engines these valves are stressed to the limit and grooves cause stress risers that snap the valve head off like a dry twig in a tornado. Valves are engineered to be as light as possible yet be strong enough to withstand the high stress. In doing so we must take a small hit in efficiency in order to pull that off.

[@rivernorcal679]

The grooves are on the face of the valve not the stem. Only 7000 of an inch cut. Already went through strict patent testing in racing engines. Don't want you to dismiss our product if it can help people out there.

[@mikecondoluci53]

HI DARIN IM 62 HAVENT DRAG RACED SINCE 85 I GOT THE ITCH AND HAVE TO DO IT AGAIN BEFORE I CROAK CAN I PAY YOU TO DESIGN A CAM FOR MY SET UP?

[@Baard2000]

Therefore I test at at least 70" of testpressure. To create the best resemblance of the reality.....

[@Dr_Xyzt]

When you taper a runner aggressively, don't you ruin its ability to resonate? I saw your site and a major fan of your BV3 heads.

[@darinmorgan3520]

The BV3 heads are not my design. Thats all Edelbrock. No, you dont "ruin" its ability to resonate but it does attenuate the signal somwhat. More taper decreases amplitude a bit but in return it broadens the wave length or time making for a wider power band.

[@Dr_Xyzt]

@@darinmorgan3520 Thanks for the reply! Keep your oil pressure up!

[@scottosborne8735]

5:45 mark

[@byron3373]

Is it good practice to wear a respirator when porting ?

[@darinmorgan3520]

Very Important. You need good ventilation as well.

[@adamarndt7617]

Darin: Your rules-of-thumb on runner volume (length + increasing opening with reasonable taper to get to your runner volume goal): how / how much do they change when dealing with a dry flow intake? -Particularly when dealing with a long-runner intake with bigger flow losses? -I'm assuming this is a situation where "runner velocity be damned", to a certain degree, or at least where more air volume and flow is more important vs. velocity through the runners? (Extreme example: GM TPI ultra-long runners and their extra losses from that huge, nasty curve...). [Edit] Nevermind... I read video #2... I think I get it now. I need the velocity to fully fill the cylinder even if it's not important to keeping fuel from falling out going from my plenum to my runners. Higher velocity = higher pressure on my reflected waves and more air can be stuffed into the cylinder by delaying the intake valve close when someone like Mr. Mike Jones properly specs my cam...

[@darinmorgan3520]

In a dry flow induction system everything gets smaller. The fuel isn't taking up space so valve sizing, area and taper get smaller. How much, I cant say. Not an area I have dwelled into much. DI engines are a disaster as far as racing but a god send to EPA standards. In low speed engines its fantastic.

[@adamarndt7617]

@@darinmorgan3520 Thanks!

[@darinmorgan3520]

Changes quite a bit! Look at the LT1. Although I hate that head design it does show how much smaller you can make the intake valve ( 2.200 LS7 verses 2.125 for LT1)

[@TropicBreezeRealty]

7:40 are you referring to unshrouding valves?

[@darinmorgan3520]

Unshrouding the valve refers to opening up the chamber to the point where its no longer a restriction or impedance to the flow,. Moving the valve as far from the bore wall as is physically possible is also a form of unshrouding. Pressure recovery is optimizing the unshrouded valves available area to control the flows deceleration into the cylinder. Attaining uniform air speed as possible around the circumference of the valve is the primary way to optimize the pressure recovery. An unshrouded valve can have poor pressure recovery.

[@TropicBreezeRealty]

@@darinmorgan3520 Moving the valve away from the wall (smaller valve) and not moving the chamber wall away from the valve? Thanks for the reply

[@TropicBreezeRealty]

@@darinmorgan3520 Where would be an ideal location in a sfb edelbrock combustion chamber to remove 1-2cc to decrease compression? I was thinking the quench area near the exhaust valve.

[@darinmorgan3520]

@@TropicBreezeRealty Please clarify that question. A reduction in valve size may or may not be a prudent decision depending on the CFM demand of the engine but that is not unshrouding. It takes hours to explain this topic. thats why I put together the Advanced Induction course with ten hours of video and everything else that comes with it. This subject matter can not be well explained in a simple txt. Your questions are great but the explanation is more complex than I can explain in 120 words.

[@darinmorgan3520]

@@TropicBreezeRealty There isn't anywhere in the chamber to remove material to gain CCs because the chamber is already to laid back as is. Dish your valves. That will get you there. If they are already dished, take it off the piston.

[@user-jp2el2uw6i]

The carburettor turns a liquid (fuel) into fine droplets in which state it can be ignited by the spark plug; yet as depicted in this video, and governed by scientific principles, the plenum in a 'tunnel ram' manifold it is turned back into a liquid, and has to be converted yet again into droplets, buy shearing it off of 'sharp' edges; makes no sense really when carburettors are designed to atomise the fuel in the first place!

[@fantaseahorse4696]

why does this guy keep mentioning turbulence ? the entirety of the air charge is turbulent. The damn air in your bedroom is turbulent