Will you make a video on the stock gx200 kart racing head they typically flow 40 cm and alot of misinformation is in the industry on this topic as the "pros" seem to not be on the level us real old timer experienced builders have therefore selling false information in the form of expensive junk. I surmise you can get 1.5 times the flow numbers from these heads with budget friendly parts. It would help more kids get into racing and engine building.
TLDR: The "pulsing intake of an engine" causes the cotton fibers on the K&N filter to "vibrate and flutter" which catches dirt particles while letting air through. When tested on a constant airflow test bench, the fibers don't vibrate but instead "fold in" and don't catch dirt. I'm unconvinced and think that if that is true there should have been a test done by now showing the K&N filters tested on a engine based bench setup so the vibration is present. K&N should be able to produce this instead of expecting customers to take their word for it.
Do hydraulic lifter and solid lifter camshafts have the same amount of taper ground into them? Do hydraulic and solid lifter faces have the same amount of radius as one another? Do GM, Ford and Chrysler engines from the 1960's and 1970's all have the same amount of taper and the same radiuses?
Hello Mr Vizard how are you. Hope you're doing well. I'm praying for you. What are your thoughts about Ohio forged cranks for Pontiac. Butler has high quality components but they are a little higher priced and I was wondering if I can buy direct from Ohio forged
Hello Mr. David hope you're doing good. This might be a dumb question. If a guy is building a street engine is it possible to have cylinder heads that are too good for his build? The reason I'm asking is because I'm building a power combo that will include a ported cast iron dual plane intake because the hood clearance on my firebird won't accept a performer RPM, recalibraded quadrajet but I'm wondering if throttle body fuel injection would offer a more consistent fuel mixture since it doesn't require a pulsed booster signal like a carburetor and there is no booster in the way of the flow for short clearance, a pair of good performance factory iron heads that will be modified for better flow and I am still debating what kind of valves to get and weither I should use aluminum full roller 1.65 ratio rocker arms or stamped roller tip 1.5 ratio rockers. Does valve spring pressure matter with the different ratio rockers? camshaft power band will have a maximum peak at 5500rpm because its a 400 and they are torque happy engines. I wonder how much and when I should come to a stopping point at my cylinder head modifications. I have read where some professional porters have gotten up to 300 cfm out of the 2.11 inch intake but the exhaust I think got 240 cfm. Stock they flow 180 exhaust and about 220 cfm on intake. Thank you Mr. Vizard
I had a 1977 El Camino it had a 305 2bbl it was a poor excuse for a V8. If you use that cam for your stock baseline it would be easy to get 100 hp increase from a cam swap in a 350 😄. The smog cams of the 1970s had such a small ramp on the top of the lobe you can cut your finger on it 😄 and idle so smooth you didn't know the engine was on and that's probably why a lot of starter gears got ruined in the 1970s 🤣
Thank you for making another very interesting video Mr. Vizard you are more interesting than watching my favorite TV show. I have calculated the amount of CFM a 50 cubic inch single cylinder of any engine flow demands at 5500 rpm it is 1000 CFM when the piston is traveling at its maximum speed in the middle of the cylinder. I did this by multiplying the stroke from radius squared times pie times 5500 rpm and calculating the bore squared times the the amount of stroke in one minute at 5500 rpm. Somehow I arrived at 1000 CFM. If a cylinder head intake flows 300 CFM it will be able to catch up as the piston slows down toward the bottom. Is this an important thing to think about ?
Hello i built a 350 chevy with flat pistons,stock vortec heads,.015 steelshim head gasket,.040 quench,long tube headers,weiand street warrior aluminum dual plane intake,750 cfm quadrajet carb rejetted howards hydraulic flat tappet cam,.470 lift int and ex,275 deg adv duration int and ex,108 lsa,104 icl,59 deg ovelap install straight up.this engine is in a chevy c10 with a turbo 200c 3 speed trans with lock up and 3.73 rear ratio.this combo has no low end power at all.pulls strong from 3000 to 5500 rpm.is there something wrong with this combo? Won't spin the tires at all from a standing start.no idea where i went wrong,any help would be appreciated.thks.
DV IS IT POSSIBLE TO TALK TO YOU ABOUT A SBF 289 I KNOW YOU HAVE EXTENSIVE KNOWLEDGE ON THEM IM LOOKING FOR THAT 500 HP COMBINATION WITH A 4 SPEED TRANS AND WILL BE DRAG RACED AND HAS A MINIMUM WEIGHT OF 3100 POUNDS CAN'T WAIT TO HEAR FROM YOU THANK YOU
Im currently watching this video. I have a 1965 283 sbc , .030 over , intake is a 1966 283/327 GM "H" cast iron square bore intake , the one supposedly known as the 300 hp intake. I did some mild match porting, and just cleaned up the flash and burrs that gm left. One water passage was almost half closed by a huge casting flash. Heads are original 520 powerpacks ,1.50/1.72 and has had hardened valve seats installed. Going into 2 inch ramhorns . Edelbrock AVS2 1901, 500 cfm. Silver pop up springs. Pulling a solid 18 hg at warm 650 rpm idle . Cam is summit k1102 , 262/272 duration, 204/214, .050 420/442 lift...very similar to the Edelbrock Performer Plus cam grind. Right now, its timed at 12° base and the distributor is a bit of a combination of msd gm style hei ( no box) and a jegs blueprint. Reason being i took the best parts and combined for max voltage output and higher rpm allowance. The advance is 22° according to the msd part, and i put the vac pot from the jegs unit onto the msd carcass , for more adjustability , i suppose. So, im assuming a total of 34° timing at 2750 rpm. I see most if your videos are based on the typical 350 and use holley carbs. How can i apply the info here to my application . In a sense its still apples to apples being in the sbc realm , maybe more like a macintosh vs red delicious...if you get my meaning. Just a cruiser set up..1951 chev 3100 bodied, 1983 s10 chassis, th350 with a Ford 9 inch 3.25, open, p225,70R15 ...with an air conditioner. Roughly 3250 lb vehicle.
Hello Mr. Vizard hope you're doing good. I am glad I saw this video. It taught me a lot about the cylinder head I am working on. It looks a lot like the way Pontiac V8 heads are made on the exhaust. The flow is more predominantt on the cylinder wall and I am thinking if I port the Pontiac exhaust the same way as this it will flow better.
Plastigauge has to be one of those inventions that keeps on giving, easy to use, very affordable that anyone can use, this stuff eliminates every excuse folks can come up with yet very few actually do and after wonder what went wrong..
David, I really like the information you provided with regard to the 706 head. What I would like to see is more information with regard to the chamber modification for these heads. Specifically, what is your prescription for modifications to exhaust scavenge and intake charge swirl? What is the "fill" material used to increase intake charge port energy? Thank you!
I took a leaf blower (I don't have a flow bench yet) and blew air at the intake port and noticed most of the air comes out half of the valve and hits the wall of the combustion chamber and very little if none at the short turn side of the valve. I noticed when you port the bowl it sort of has a shovel appearance at the combustion chamber end unless my eyes are deceiving me. It looks like the sides are a little bit narrower than the place where the wall of the combustion chamber is. This would make sense
Thank you Mr. Vizard. I have a question about the exhaust short turn radius. Going inside the exhaust valve bowl is it good to lower and taper the floor of the short turn radius inside the exhaust bowl?? Thank you. The shape of the short turn radius on intake and exhaust is challenging for me to grasp
I know this is an old video, but for what it’s worth, I know a lot of those that run the Baja 1000 rebuild their engines afterwards due to the harsh conditions. They aren’t exactly going for engine longevity like most of us are.
Sir, I agree with your statement that there are few, of any, properly built headers. Have played with a few designs that make claims for good performance, and just like you expressed, found them less than "as claimed". I would disagree with the statement that you don't need back pressure. To qualify this, I am just going to point to the cam profile as the yes or no. If your cam is designed to mitigate back pressure losses, then, you need some of the backpressure to mitigate tossing the fuel out with the exhaust versus burning it. However, if the camshaft is designed for your need, then, I agree, less back pressure will always be better. V/R Chris
