Probably the best bang for buck channel on KZbin! 👌
@rotaxtwin3 жыл бұрын
Mr Vizard, you choose your words most carefully and it makes for good quality information. Cheers to your efforts.
@thomasward45052 ай бұрын
I watch this video again and it does seem like way more information and some practical views. I like seeing you do the actual porting work
@firsteg952 жыл бұрын
Sweet info especially the comment on economy with a larger exhaust valve
@williamolsenii12293 жыл бұрын
I have watched all of Davids current videos and read the BMC A-series materials during my SCCA racing days and can say there is a lot of useful material there if you're willing to dig it out and do a little home work. He doesn't just throw all the answers out there but inspires you to think about things.
@markstevens73932 жыл бұрын
Huh h huh HK
@kylemilligan7523 жыл бұрын
Thankyou Mr Vizard. Been a fan for many years and have a shelf of your books.
@bradygies99943 жыл бұрын
I'll sleep on the floor. Just teach me all you know lol. This is a blessing. I'm wanting to build a ford fe. Sadly I live on the left side of the country.
@muskyelondragon3 жыл бұрын
Sad indeed, I'm stuck over here too.
@davidparker96763 жыл бұрын
There are good engine guys over her on the left coast too. You can always book a flight to take one of DV's classes.
@flinch6223 жыл бұрын
I always learn something. This video really underscores how application specific needs translate to why there's no such thing as a bolt on head - some work is always required, even beginning with a really good casting. Keep up the great work!
@pokebass13 жыл бұрын
As a novice cylinder head porter, it is intriguing to see methods I've never seen before. I'm an avid hot rodder, and want to be regarded as a man who can build a high performance engine. I greatly appreciate your videos, as they've opened my eyes to many things I've never known before.
@crashtestperformance35962 жыл бұрын
I have been running mild street supercharged engines for over 25 years. I have always thought that the exhaust side needed more attention. I have also read some of Davids books and I really like them. Im so sorry about his daughters fate.
@nitrousshovelhead3 жыл бұрын
thank you mr. Visard. I have been reading and using the information from your books since the 80"s when I read your book "nitrous-oxide injection". I am hoping you start having your seminars again so that I can attend.
@mossranchoutdoors7249 Жыл бұрын
Same here, I've learn a ton from Mr. Vizard. His nitrous book is my favorite.
@juhanahuovinen3 жыл бұрын
Thank you Mr Vizard. This video encourage me to continue engine buildings not in such a general way. Forexample for a rally engine I might have: - 2 litre, high comp and NA - 4valves per cylinder and exhaust valve 85% from a intake valve. - cam duration from 1mm lift: 220 degrees.
@elviswon68952 жыл бұрын
you should do a line of cnc heads based on your work. I would think one of the major aftermarket head manufacturers would be interested. Port, scan, cnc.
@troymecey3 жыл бұрын
Waiting patiently for your next book. I'm not a Ford guy but I will still buy it, because I like to learn.
@johnparrish92153 жыл бұрын
I've only bought two of his books, I need to get them all.
@troymecey3 жыл бұрын
@@johnparrish9215 I'm pretty sure I have all his books except for the ones he wrote about the A engines. Just the SBC, BBC, Holley and the porting stuff, etc. I've been buying his books for probably 20 years. Great stuff.
@troymecey3 жыл бұрын
@@johnparrish9215 some are really hard to find and I scoured Ebay for months.
@muskyelondragon3 жыл бұрын
The man is a true master craftsman. Decades of learning and research at the highest level.
@thegeneralstrike67473 жыл бұрын
Boost measurements come best when the Intake Valve is Welded shut. I prefer MAD equations to measure just the volume of fuel I can combine with that volume of air within the cylinders. I will leave the welding to the frame builders.
@trentm79643 жыл бұрын
Thanks. Fantastic information.
@patrickmoore10173 жыл бұрын
Fantastic David. Keep up these great videos!
@tomhamilton91403 жыл бұрын
Great to see the SB Ford head build.
@MrScoopage3 жыл бұрын
This is race winning advice! Amazing learning experience thankyou
@superkillr2 жыл бұрын
Race to the back...nobody uses any of this info where winning and money are on the line. Maybe some chub making youtube videos, but nobody that needs to make money in real life racing uses any of this information.
@Classiccarbscouk3 жыл бұрын
Very nice work, thank you for making these videos David 🏁😊🔥🛠🤘
@ts3023 жыл бұрын
Please run these heads on the dyno. I'm also interested in the Trick flow Heads. Thank you Mr. Vizard!
@muskyelondragon3 жыл бұрын
Mr Vizard, I consider you one of the few men on the level of Gale Banks. I can give no higher compliment.
@Billybops50003 жыл бұрын
Awesome video . Hope to watch all your videos , the nitrous related ones first. Thank you Mr. Vizard.
@thomasleclair74182 жыл бұрын
thanks again David,,,,,,,Knowledge is inspiration and the mental tool for success
@stevehammel29392 жыл бұрын
Thank you, David, for an enlightening video.
@joshmarmolejo79803 жыл бұрын
Could you please show a video on LS heads? I’m interested to see how cathedral ports react to porting.
@firstrespondergarage2 жыл бұрын
👍 very nice. I'm going to have to dig out one of my 305 heads and try this for a 400... I have a 6/71 roots. I'm thinking the shallower chamber will help with the unshrouding...it just a thought I had.
@Éber.R.Pereira.X Жыл бұрын
Obrigado por dedicar o seu tempo para ensinar. ⚔️🇧🇷⚔️
@barbar99193 жыл бұрын
Thanks again for your time
@dirtfan053 жыл бұрын
Excellent info as always DV!
@rightsidelanechoice77022 жыл бұрын
I’ve heard of people using those balls during flow testing inside of the port to find dead air in different areas while watching the flow by restricting it with the ball.
@stevesloan67753 жыл бұрын
Im a huge fan ;] I have a 90 tho over sized Kent cross flow with 244 kent cam, 11.1comp. My question is can this go supersonic air flow? going by this upload, my i600 flat heads flows heaps more on the exhaust port compared to inlet. mega revision.... surely
@levidale51943 жыл бұрын
Hello Mr. Vizard! Big fan of your work, I've been reading/studying your publishing's for over 2 decades now. 20 year young hot-rodder now 44 how the time flies! Anyways I do have a specific question about the content of this video. If you didn't CC the chambers after the work to know for sure the size increase (if you do know please share) what would be your guess on how many CC's you added to the combustion chamber.
@matthewsaville35923 жыл бұрын
What % of the exhaust valve size increase is due to the lower compression compared with the extra due to increased oxygen from turbo/nitrous?
@martybrozek79733 жыл бұрын
The man, the myth, the legend !!!!
@frankchapa41652 жыл бұрын
I'll bet Einstein asked David for advice!! 👍👍
@davidvonanderseck86493 жыл бұрын
I have a question 454 or 460. I just learned that the 460 is actually a really good block. I always been a Chevy guy. Are 460s more difficult or expensive when it comes to heads. I noticed a lot of guy go straight to aluminum heads.
@marthamryglod2913 жыл бұрын
The 460 heads are massive choke points to making good power without a big overlap. Many design features can not be overcome, so aftermarket heads are a huge improvement
@davidvonanderseck86493 жыл бұрын
Thanks Dave a lot of good stuff thanks fir the videos. I’m sticking with Chevy
@DaveMcLain3 жыл бұрын
The factory 460 heads are generally superior to comparable heads from other similar production engines when it comes to making power. They can work well for very little money in a lot of applications with the right modifications. Check out the porting guides from RHP they are worth it.
@laiky713 жыл бұрын
David, could you provide info on a suitable zirconium oxide coating for intake manifolds like you explain in your book? I have been unsuccessful in trying to find something acceptable that works.
@Hitman-ds1ei3 жыл бұрын
Time to take a grinder to my supercharged 427LS heads before I bolt them on
@gregperry76553 жыл бұрын
According to Richard holdener, and his extensive dyno testing,.. the more hp an engine makes N/A, the more hp it will make under boost. This makes sense mathematically as well. If we take a 300hp engine, and double the atmosphere pressure (14.7 psi boost), it will make around 600hp. Therefore, why would you change the valve sizes at all, specifically? If it does not improve the HP N/A, it will not improve the HP under boost (over a different valve size combination), so why do it?
@superkillr2 жыл бұрын
Don't come in here with your common sense and dyno backed theories. This is for DV fan club chubs, to say how amazing his un-used by any serious race team or manufacturer in the world ideas are.
@michaelgunning3472 жыл бұрын
What Richard and david are doing are 2 different things , Richard is bolting on boost and starting with max n/a is a good point , david is increasing efficiency of a given set up and if u watch again he increased power with out sacrificing reliability as cylinder pressure was fine , also he is watching controlling back flow very important on a turbo , u will need to go deeper ,
@aaronhall77402 жыл бұрын
That works in theory but you loose efficiency with higher pressure ratios (charge temp and turbo shaft speed) and also back pressure
@earlwest60052 жыл бұрын
@@superkillr So I'm curious, what technologies are you using or referring to? I went to your channel and found only 4 subscribers and 0 videos? We may be chubs, however we are trying to learn. Not everyone is exposed to top racing technology. So If you know some share it with us. I would be just as grateful to you for it. Thanks
@cassandraclark856810 ай бұрын
@@superkillris it even possible to get almost double the power from a 75hp shot, not in my opinion. Love how he also says that nitrous is unreliably repeatable, not in my experience. How can he even measure 1% of what goes on in an exhaust port, 500+°c temps & over 1800fps air speeds tells me no you can't & 35yrs experience in this game says the same
@jetjox20003 жыл бұрын
Perhaps I missed it, but how should the 75% int to exh ratio be better optimized on a forced induction engine? Greater than 75% I assume?
@marvingvx13 жыл бұрын
Yes - but watch it all again so I don't have to take a page or so to explain.
@BBD4011 ай бұрын
What iron heads should I seek for my twin 454 carbureted marine engines?
@terrycarter89292 жыл бұрын
What is the ratio ideal for forced induction compared to the 75% on naturally aspirated?
@BEYTEK3 жыл бұрын
Super imformative video!
@johnparrish92153 жыл бұрын
Ya, I saved it so I can watch it ten more times.
@exploranator Жыл бұрын
Since a blower or a turbo crams air in, as does nitrous, why not have an exhaust valve same size as intake valve? Then you can really lean on the boost or nitrous without concerns about scavenging at all. Scavenging would be excellent due to the area rule favoring a bigger "curtain" of air escaping around the exhaust valve at early lift?
@morganmclean17903 жыл бұрын
your last name should of been wizard lol! love your vids if you see this give me a link to see yiur fir sale products!
@kenswitzer41333 жыл бұрын
The least resistance a pump has the more efficient!
@GriffonGrowl Жыл бұрын
I was confused by the drawing of the exhaust port at 26:49, is the solid line the gloor of the port and the dooted line the path the air will take?
@rollyalberto95712 жыл бұрын
THANK YOU SIR!!!
@jrheavyduty2 жыл бұрын
Watching this to learn if there’s something useful for diesel. Anything you could share
@Daryl-l3x11 ай бұрын
I use the porting tips on my idi diesel and it works well,not so sure about D.I. engines though.
@jarez3781 Жыл бұрын
Does this work well with a boosted engine with E-85 or a max effort mild blown/small supercharger on a sbf on alcohol?
@scottworelds29333 жыл бұрын
Awesome
@johnparrish92152 жыл бұрын
Thanks!
@Gin_des3 жыл бұрын
Thanks a lot🤝🔥🔥🔥🔥 top info
@dielauwen3 жыл бұрын
I always thought exhaust flow is more important than the intake.
@davidparker96763 жыл бұрын
Exhaust flow is important, but it is more of a struggle to get good intake flow on a naturally aspirated engine. On a NA engine, you are relying on atmospheric pressure to fill your cylinders. On a forced induction engine, you are able to overcome more obstacles to flow with increased boost pressure. Having a good flowing port and boost pressure is obviously better than relying on higher boost to force its way through a bad flowing port. Exhaust is forced out with combustion pressure, heat and the piston's upward movement. A good flowing exhaust will aid the turbo and help scavenging. Exhaust flow is important, but not more important than the intake. To make more power, you still need to maximize the oxygen and fuel in the cylinder.