here is a short article i wrote back in may on our website discussing the difference in supercharger, most of you probably know this but i figured i'd share it anyways. http://www.diamondp.com/kb_results.asp?ID=8 ---------------------------------------------------------------------- "Types of Superchargers and their Efficiency There are three main types of superchargers in today's automotive market, Root style, Lysholm twin screw and centrifugal, each one suited for a different application. While there are more types of superchargers i am only going to use the three most common types in this article. First we need to know what exactly a supercharger is designed to do, while most of you many know what one does or how it works i would still like to state that a superchargers job is to force a larger mass of air into the same amount of volume into a engine, i will explain later the emphasis on mass and volume. The Lysholm supercharger is the newest in design of a positive displacement supercharger and is more efficient that the roots style. the reason they are more efficient is because of the way they compress the air into the intake. Speaking in terms of physics, When ever u move, smash, compress anything, whether it be a solid, gas or liquid it causes the molecules of the substance to heat up, which causes the volume to expand but u still have the same amount of mass. For superchargers, the hotter the air gets the less you will have density wise going into each cylinder. So while a roots spin outwards towards the casing wall smashing the air as it spins and is then forced and compressed within the intake manifold, the newer twin screws has a male(blue) and female(pink) rotor that spins the air in between its rotors and much more fluidly, moving the air from the front to the back, compressing the air while it is still in the blower, reducing the friction and resistance caused by the air, reducing the heat as it enters the cylinders. A centrifugal supercharger is nothing more than a turbocharger that is driven by the engine instead of the exhaust system, centrifugals work by spinning multiple blades and very high RPMs(much higher than roots or twin screw) to force air into the intake, they are much more efficient at high rpms compared to roots or twin screw but they lack low rpm boost and create much more heat. A simple example of boost loss would be if you where to install a boost gauge in you manifold and block off the intakes, then heat the manifold from 70°F to 150°F the gauge would actually register an increase in boost, although obviously its not running any boost and you still have the same amount of air in the engine. The faster you spin a supercharger the more it will heat up the air and the more the volumetric efficiency will drop but the boost will still show an increase. If you can build an engine to actually withstand it, you could theoretically spin a supercharger so fast and heat the air so much it would actually become parasitic to the engine. (I don't recommend that) On the reverse side of intake modification, take an engine that runs NOS. NOS is used in high performance engine for short duration to temporarily increase hp, it works by being injected into the intake system and does two things, one it super-cools the air and two, when the nos enters the combustion chamber and reaches 296°C the nitrogen and oxygen atoms split releasing more oxygen so the air becomes more dense thus you are able to pack a larger mass of air into the same amount of volume. You might be thinking though if u take a large 1471 blower and throw it on a engine you can spin it slower than a smaller 671 and still get the same amount of compression and since it is spinning slower it wont produce as much heat, and your right but you have to factor in the extra weight and resistance that the engine has to push, the heavier your components are, the more hp it will take to drive the supercharger."
just an update, castings are still at heat treat, compressing and editing the 200gig of video i have so far (so much fun), and our mazak 500 is down because of an tool change error we cant seem to get lined out, have a guy coming in this week i think to look at it. Just to see how patient everyone is though, do you guys want me to go ahead and create a video of what i've done so far, design-casting and make a separate on of the machining or wait till we get all the machining done, which will be probably no less than another month?
Sure, why not! This is great stuff, and proof that the American spirit of manufacturing is still alive... Was pretty cool to hear the story of the business from your dad too.
finishing up on a video of how cores work in a mold using the blower as an example. should have it uploaded in a bit and posted.
here it is, now this video is just part of my basics of foundry, not the final video of making the supercharger, im just using this build to show how cores work.
Day.... 40 somethin : housings are back from heat treat, Mazak guy is in working with our maintenance men trying to get the 500 up and running. Keeps faulting out after a tool change. As soon as we get a scrap one we will send it to X-ray out for lab testing, Which may or may not be this batch. i do however have some photos and of the other xray job along with lab results of tensile and yield, poured from the same furnace, ill post those in a bit.
Day 45ish.2: Here are the X-ray of the castings we poured out of the same furnace that the blower where poured. These and the blowers are A356.2-T6, A356 is the metal, .2 is referring to its state and T6 is the heat treat type. This casting past xray, the photos where taken after heat treat. if there was any defects, you would see black spots in the photo which would be gas bubbles or porosity within the casting. I've also blocked out certain info in the photos, we don't release any confidential information of customers or vendors unless we have permission to do so. ----------------------------------------------------------------------- This photo is of the chemical composition of the metal. ----------------------------------------------------------------- This photo is of the Tensile, yield and elongation. ------------------------------------------------------------------------------ Now, for those of you who might not know, tensile strength is a measurement of force applied upon an object when it is being pulled apart, other forces of measurement can be compressive and shearing. Yield strength is a measurement of the force required to permanently deform an object. The closer the yield point of a substance is too its tensile, the longer it will hold its form but once deformed it will quickly break. rubber bands is a good example, you can pull a rubber band and stretch it very far, but once elongation stops, it will break soon after any more force is applied on it, so its tensile strength and yield strength are almost one in the same. ----------------------------------------------------------------------------------------------- Here is a photo of solidworks standard for 6061-T6, most commonly used billet alloy. -------------------------------------------------------------------------------- Now, even though solidworks uses this standard for 6061-T6, it does not mean a blower made out of it will have these results, every casting is different and the section you test will dictate its results. Theoretically speaking though, lets say we have a blower made from A356-T6 and 6061-T6 from the results above, how do they compare? Ignoring elongation, the A356 blower will have a wider range between deformation to failure while a 6061 will hold its rigidity 2,561psi longer but soon after deformation it will fail, but remember, tensile is a measurement of something being pulled apart, not compressive or shearing, which would be rotors pushing against the housing.
The post from your Dad brought a tear to my eye. It's just great to see a real working family manufacturing business run by a great family! Kudo's to you guys and I hope you get back to full production.
Just to let you guys all know what you do for this build, we check our site traffic every week, these last two dots are the days after i released the "Cores & Coreboxes" videos. This way i'm able to show the top brass(my dad ) how the videos affect our site traffic then he lets me make more videos and build more things for you guys to watch. So thank you for the support.
Here is what happens when a coreprint breaks in the mold and the core shifts during casting. This casting was machined, and a few thousands more and some bad things would have happened inside the CNC. This castings is a actually a roller for an automated greens mower being developed by a company called Precise Path, we have been doing the casting and machining for one of the rollers on it. my uncle, the one that owns the shop that i made the blower pattern in, designing and made the pattern and corebox for this.(core break was a result of a bad core, not the tooling) Here is a video of the thing, you can see this roller at 0:39 of the video, its the small one between the bigger front and rear rollers. <iframe width="560" height="315" src="http://www.youtube.com/embed/vY9u1ZgOiMM" frameborder="0" allowfullscreen></iframe>
Wow, this is great. Thanks so much for posting all this for us. Great detail and explanations for all of us that know a little and like to learn. Keep up the good work. Frank
this is awesome !!!!! I always wanted to see this process for car parts . worked in a foundry in colorado doing bronzing back in my misspent youth
Just to let everyone know, i am finishing up on the first part of the video, everything i have shot since the start of the build, just need to do some commentary and minor editing and it will be ready to upload, hopefully by tonight.
This IS by far the best read I have had in a LONG LONG TIME!!! I never knew what the process was to casting something, and as someone else said I couldnt wrap my head around what was going on till I saw the finished product. I am so glad that the next generation has picked up the torch and is moving forward in our hobby. I have always wanted a blown car, NOW, I want a blown car with this blower! Not sure my pockets are deep enough, but, if they are make mine for a PONTIAC and if you get some free time make me some finned pontiac valve covers and maybe a valley pan! Thanks for this thread!!!
Here is part one, video software keep screwing up, thats why it was taking a while. <iframe width="560" height="315" src="http://www.youtube.com/embed/zU34no3VLHI" frameborder="0" allowfullscreen></iframe> If anyone wants to help us out, feel free to share the video on any other forum
Nice job on the video Garen. We were contacted by a high school in Ohio to use Garens video's for education purposes. Maybe he can get some young people interested in the art of patterns & castings. Our manufacturing skills and even the interest in manufacturing seem to be dying or worse slowly killed in this country, especially in the younger generations. Thank God for hot rodders and car guys who keep the tradition of the ''do it yourself'' going.
Grab one of the adapter plates and decided to get it machined, don't have an intake to show you how they lay on and weld down but here is machining it and the after (without bolt holes) --------------------------------------------------------------------------------- Machined it on a bridgeport. thought i took a picture of cutting the other face but apparently my phone didn't feel like working. -------------------------------------------------------------------- Done ------------------------------------------------------------------- I ended up having to take off 0.005" for the finishing cut to keep it from flexing or moving. It might not look like a clean cut but a lot of the marks are from sand stoning it afterwards.
This is just too cool. I was talking about this thread to my son's girlfriend's dad as we watched her play high school basketball. Turns out, he's one of the guys working on this! Just saw his pic there (George). He was telling me how close the tolerances were at this shop compared to the industry standard. Keep up the good work!
Yep, George is our greensand and airset foundry manager, he's been working for us for 15 or 16 years, before that he did brass and iron foundry work. Most of my foundry and molding knowledge comes from him, he's in the video a lit bit too.
Went up to meet with the Tippmanns to discuss business today, figured id post a some photos of his bikes he has. He told me that this indian was actually used in a movie but i can't remember which one he said. ---------------------------------------------------------------------- Tippmann Sr. on the left working on one out in the shop. -------------------------------------------------------------------- .22 cal automatic BB gun. (tippmann was acutally a gun smith making small scale .22 cal browning style machine guns before he created his paintball business back in 87'.)
We use to pour brass , it is nasty, we stopped around 96'(before i was working). i've been told the stories from the other workers and getting the brass chills and how horrible it was the first few days working or if you inhaled to much.
.22 cal automatic BB gun. (tippmann was acutally a gun smith making small scale .22 cal browning style machine guns before he created his paintball business back in 87'.) [/QUOTE] I saw the Air-Ordnance videos of this on Youtube. I want one!
How do you bolt it to the manifold? I don't see the original style GM lugs that were cast into the case for the mounting studs.
The adapter is made to be welded to the manifold after a pocket is machined into the manifold to accept the shape of the adapter. The manifold and adapter looks better if it is welded on the inside but can be welded around the outside. There will be a few flat pieces that may have to be cut and fit to insure a good seal depending on manifold design. We will have the proper diameter holes and bolt pattern already machined for the 671 or 871 with both sides faced when they become available for purchase.
The Jalopy Journal
