Ok, how about this then! Has anyone wet-flowed any factory buick head and any TA or Bulldog cylinder heads? Why you ask? Simple, this tells you if you have a well designed cylinder head or not. Its that simple, if you disagree, I recommend you all to read alittle! There is plenty of discussion on that.. I can only go so far without having my own flowbench and wet flow! I'm up for some teaching though. I don't care if I gotta buy parts to do my project, but I still want to use used parts to even challenge my self even harder and not make it easy . here is my question to you guys, why are you so down on me for even trying? I rather go big then start stock. I have alwvays done this and done my home work beforehand. That's where you should be happy and not down grading me.I challenge you 85d to do this and test it, you work with cylinder heads and modify them pretty well. Now go do a canted valve buick head and make flow. Devon, go buy some crackers and some cheese spread and watch some tv. or the both of you can actually help on this thread! Gary M.
Gary, I hope you don't think I'm being too snide. I was just hoping to keep the thread (even though it's yours) more on the topic of head porting rather than blocks and other subjects covered to great extent in other places of the forum. I think I've done a lot to encourage some interesting conversation in this thread. I have even gained some great contacts from this, so it should be viewed as a positive. There is a lot of jesting, and on a public forum you will always see that, but it's up to you how it affects you. The "jokes" I see don't seem to be insulting, more like something one might say to a co-worker to set them a little more in line with their way of thinking. After all, they may have been there before. When folks give me humor I think, "what am I missing here...? Oh, that!". [insert "Frye" meme here, hmmmmmmmmm] Just as you keep reinforcing the value of wet-flow testing, others are saying to you that they have been down that road with the block, rods, and pistons...many times. The cost is a lot of broken parts. I listen closely to this type of advise, as I'd rather see someone else's pile of broken parts than to have mine rapidly un-assemble itself. Wile E. Coyote never sees it, until he's way off the cliff. I think anybody that has read into wet-flow universally agrees on the benefits. Nothing new here. Not disagreeing with the value, goals can be reached without it. Show us yours. Please utilize other parts of the forum, too... there's a lot of info here! I've been pretty encouraging here.
I just did a simple search on wet flow and nothing about pictures or anything about bbb cylinder heads being wet flowed! How can you say you can get the same results without using a wetflow? That's like me saying "I can port cylinder heads and achieve the same results as pro's do without a flowbench! It simply won't happen. How can you tell if your fuel isn't pudding in a corner or if it is causing a major vortex over the spark plug how about this, A good designed cylinder head (Port design, valve angle, valve face angles, combustion chamber design and many other aspects not listed.) Will allow lower timing but every single buick head designed still has the same timing? These are the questions I would like answered and no one has answered them! I'm not no pro but not a beginner either. From what I have called upon to the pro's and have read, no one has designed a real good head yet. Their still basing it off the same old Stage design but slightly modifying it.That's why I mentioned the flowbox to ease the cost in redevelopment! its cheaper that away. here is another thing and its not new either, what about 3D printing? There cheap and easy to run. Yes, I may not have this tools. but a a good company should have them. please elaborate on this. Gary M.
Not sure why my posts seem to offend you, Gary. I'm attempting to encourage you to go forth on your quest. Once you reach your destination, share the results if you would. I'm also attempting to speak to you as an equal comrade. I have no arguments with you, just different opinions based on MY experiences. I think that's the point of all this, right? I did not claim that dry flow development equals wet flow development. I simply said that goals can be reached without it. In a previous post I said specifically that MY goals have been met without it. I've also addressed ways that atomization improvements can be "seen" without being "seen". I've shot ink or paint down ports before, just not on my bench. I don't believe that most of the members' projects here would demand wet-flow testing. I've already agreed to the superiority of wet-flow. Just because you couldn't find any pics doesn't mean it hasn't been done. I still have tricks I'm not sharing. Maybe a bad analogy but someone from GM(?) wrote this, "You don't need to build a swimming pool to prove a bowling ball won't float". Trivia points and a smiley for the author... There are some ridiculously high powered cars here, and plenty in the entire history of rodding that "the goals were met". Obviously your goals are different. You are in a position to answer your own question. Do it. Prove it. Share it. I don't doubt you, I just have enough on my plate...No one is stopping you. Hoping for stimulating conversation on ported heads. Wait, I did an A-B-A test and saw a loss of 4-6 mpg with an unported head. Anyone else? Got any cartoons on Ferguson? Holding my breath for Darin Morgan to jump in...
85d, by talking to three highly experienced cylinder head porters and developers, (I won't mention their names!) but, they even said they heard some not so good things about Buicks design and aftermarket design too. They only told me a basic few things (1. Poor port design,2. valve angle shouldve been back more of an angle not less 3. Real poor combustion chamber design.) Now, if anyone told me that, I would about flip out and try to figure out how to improve it some how That's what I'm doing. For starters, I'm doing a base line flow and wetflow then do one thing (oval port design) then having the head flowed and wetflowed. I want to see where the swirl is and how I can improve on the basic iron head first. If AM &P was successful with it, then why not give a try! I'm not scared to adventure out of the box, I want to improve not stay in one spot and improve one thing in 10 yrs. Wetflow has gained more horsepower then the invention of the flowbench it self, the flowbench only has gained in new head design 15 to20 hp every year while the wetflow gains 35 to50 a year and that's a fact from all the head developers! I don't doubt your work at all. I just a little direction nothing major but some direction. Gary M.
Gary, i am by no means a expert. But from what articles I have read and a ongoing discusion with the swirl you are talking about the big names have said they dont want swirl on race engines. I would think 750 to 800+ hp you are going to build might be considered a race engine. They say straight line flow the last article i read. Just somthing to think about.
Bob, I hope you and yours are doing OK. Prayers are out. Happy Turkey day everyone! I'm going to have to change my browser settings as a Google image search on "wet flow" left me utterly shocked!:shock: I had to stay there for a while just to be sure of what I was seeing. I'm about to show the limitations of wet-flow. The benny's are not disputed here. Another chapter in the saga of the head porting thread. Who owns the rights to this book? In terms of the combustion event, "the goal" is to release as much energy from the fuel, utilizing as much of it as possible, rather than wasting it, and in a controlled manner. The methods involve atomization, vaporization, and mixture motion prior to combustion (and some more fancy words I'm likely forgetting). The methods used and their effectivities change with the various layouts and design differences. Each tactic itself has a range of usefulness, and as they may work with or against each other, all have a point of diminishing return. Basically, the engine doesn't care how. It will let you know what the results are. I'm sure everyone here understand this, so some examples might be needed to clarify. 4 valve engines use tumble, rather than swirl to maintain vaporization (and the mixture motion prior to ignition releases more energy...). 2 side by side valves crash the swirl, rendering the tactic useless. The fuel "drops" out and mix-motion is lost. (This is generalizing, of course, I don't want some know-it-all responding with staged or biased flow within the 4v layout. Remember, I'll get back to Buicks!) At very fast piston speeds what's happening in the cylinder can destroy what's induced by the port. Tumble works well with high rpms to keep fuel vap'd and in motion. There's a reason I brought this up. I'll get back to it. 2 valve engines use swirl effectively, the ascending piston maintains and even accelerates the swirl, to potentially release more energy. Swirl seems to reach it's limit with RPMs. It can become choke, to a certain degree. (again, generalized as I'm saving more for later) One of the reasons the BB Buick works so well within it's original powerband and hp level is that the engineers designed it EXACTLY to do just that. Even with casting differences, it reaches goal. What we basically do as head porters is re-sculpt passageways for more flow, thereby diminishing some of the physical manipulation of airflow. We reverse the trade-offs knowing (or not) that less swirl is needed as rpms go up, to the point of eliminating it altogether. One way of looking at this might be... and pardon the metaphors, A flowbench tells us the volume and speed a stampede of cattle can pass a specific sized gate, or hallway. We can isolate stagnant areas and affect the direction they enter the corral. We can then utilize this data to affect a limited portion of an overall formula. Wet-flow helps to visualize strays, as well as the ability to verify what was previously "invisible". Regarding the engine, the previously mentioned vortices and rivulets. String, smoke, and obstructions are tools of deduction, but not actually "wet". ***The elephant in the room here is that the moving piston can undo your work!*** We still have to take an educated guess as to what's going to happen, and verify via trial and error! Because I've probably killed those brain cells, someone remind me if the depression test range of a wet bench has the capability to reach the peak hp level demands throughout the entire cycle. We know it shows just a single snapshot of a single condition at a time. Can anyone yet simulate the entire cycle with accuracy regarding cylinder position and depression at each lift point, as well as throttle position? I don't think that a home or shop-based wet bench can (affordably) reach depressions the running engine can. Other than OEM's, anyone dyno-ing part throttle conditions? Tougher to hold a standard there. Let's bring this plane in for landing and go a step further... Remember the video I posted showing a sequence of delayed snapshots in a running engine, strung together to resemble a movie? I would like to see a fluorescent version of this across a wide range of conditions, like rpm's and throttle angles, as well as applied load to the test engine. That would eclipse the limitations of wet flow. Well, since I'm not developing engines for OEM's, top race organizations or such... I'll simply settle for what I'm currently using. At what point is studying minutiae considered "the point of diminishing returns" in a test lab? Happy Thanksgiving, all!
Nice post Tony! Gary, an inexpensive alternative connecting rod might be a Ford 5.4L mod engine factory rod? They are 6.657" long big end width is .940" thick(needs sight narrowing) with a 2.0863" journal size and I think they have a .866" wristpin. Maybe do the research on these rods to see if they would be strong enough to handle your 750 HP you want to get and can even stroke the crank a bit to pick up some more cubes because the journal size is smaller. They look lighter than a factory Buick rod too?o No: Here is an example of a set for sale on evilbay; http://www.ebay.com/itm/Ford-5-4-li...Parts_Accessories&hash=item1e95a64777&vxp=mtr Of coarse because the wristpins are smaller you would need a custom piston of some sort, the AutoTecs would probably be the least expensive way to go new. Or you would need to be a good enough machinist to make spacers for pistons with bigger pin holes to use the smaller .866" pins to fit the rods. That would open you up to a whole lot of off the self pistons to try to make work. I'm sure it can be done its not all about forcing the engine to make more power to get to your goal, in this case freeing power would go a long way. Things like thinner rings, lighter rotating assembly, lighter valve train, roller cam, roller lifters, beehive valve springs, an oil bypass plate that redirects the oil thru an external oil pickup and so on..... Its not all about just cylinder head flow to force an engine to make power. To make this live without a jock strap @ 750 HP you will basically need to get 150 more HP from a 600 HP engine(even @ 600 HP the Buick 455 is marginal without the jock strap). Meaning you need 600 HP of force to make 750 HP so the engine doesn't destroy itself. That is 20% more HP than the non-jock strapped 455 block can handle, so at a minimum I would say to start by making everything that is weighed at least 20% lighter to start with. 20% less ring drag, 20% less friction so on and so on. Keep knocking off that at least 20% wherever you can if you can do that you might be able to get there if you are as good at porting as you think you are.GL Derek Derek
Yeah, you wouldn't want to blow out your bottom end. Good rod info Derek. I've seen entry level 5.4 H-beams hover the $200 mark. I don't recall if the OEM's are PM. Powdered metal rods have a tendency to "let go" when done, rather than distort or bend. Just a thought. Chris Skaling shared a post regarding bbb h-beams. Pontiac h-rods are close, too. BBC's might be le$$, since the subject of offset grinding came up.
Ok folks, this is what I'm talking about swirl, the vortexes in the combustion chamber not the ports. Your rt 85d, no one has yet stimulated a running engine yet! One major factor that the flow bench cannot do (Heat , Thermo expansion.) That will cause a lot of differentials! You can do all the work you want in the ports to get rt but, if your combustion chamber is off, then you'll never reach a world good head. The combustion chamber is an extension of everything between port design, port shape, valve angle and so on. Back in the 60's they DID NOT KNOW THIS, by knowing what cylinder head developers know now even say " the heads of yester years are far behind compared to today's factory built heads and let alone the all out race heads. Here is a good example, build a race small block chevy for raised port heads and see what your power level is! Then just change to Sb 2.2 bowtie heads Nite and day difference in power. Damn, I just consulted on a 750 hp stroker 421 smb chevy that makes 780+ hp and that was with AFR 235 heads, I talked to David Visner on this and he said that was pretty good but, if you really want to wake that engine up! Install the SB2.2 heads and hang on! Now, why haven't anyone designed a cylinder head like the SB2.2for the BBB? That head is old now but still one of the best designed heads of all time! Gary M.
Hey Chris, here is what AutoTec wrote about their 4032 piston line; "AutoTec is a High Quality, Precision Manufactured piston option. That comes at a very respectable price. Our Design Specific Forging allows us to manufacture our parts with less machining time, thus allowing us to keep production cost down. Then pass that savings on to you, the customer. Made out of 4032 High Silicone Aluminum Alloy, it has great wear resistance, a low expansion rate, is very durable, and is very low in friction. These pistons accommodate multiple uses including. Your local auto shop, muscle car restorations, performance street rods, as well as many spec racing classes. They can also withstand mild nitrous kits and small turbo or super chargers. Just about everyone can benefit from the excellent value the AutoTec line carries. Keeping in mind these pistons were originally designed for about 600 Horsepower. In Small Block applications, we have customers that frequently fine tune engines that yield 850+ Horsepower with a bit of Super Charger boost. Bore, Ring Pack, and Compression Distance changes can be made to any shelf part at no extra charge. Meaning that if you do not see your application listed in the guide, we can make what you need without charging a custom price. Every part is made with same high quality machines and tools as our RaceTec line including diamond turned ring grooves, and skirts. Not to mention our parts are 100% made in the USA." Basically is a customizable piston for an off the shelf price, with only 750 HP as a goal is 100 HP lower than what other customers are achieving with these pistons. Chris, have you ever used these for any of your engine builds?(you may want to look into the AutoTecs if you haven't yet, they are a forged side relief design that makes the piston lighter and stronger like what nascar runs) I have not, but have used different brand 4032 pistons with great success. A 383 sbc build I've done has been spun to 8,500 RPM without incident and spun to 7,500 at a regular basis using 4032 forged pistons that is at the 580 HP range, soon to be more as soon as the Dart heads get ported. So I would imagine that the AutoTec pistons would work great for Gary's "build". If cast pistons can make 500 and some times more HP in a 455 build then surely 4032 forged pistons can handle 750 HP no problem.:TU: Derek
That would be cool. One was designed for a Olds. I don't know if it actually made it to the engine, though. It really comes down to commitment. One could "easily" buy a single off Ebay, digitize the features, and carve one from solid stock, altering features to fit any platform. It's been done. Anyone that's at least operated a CNC mill will tell you it's a HUGE undertaking for the ROI. I'm not sure if I agree about the engineers not knowing, while making polite observation as to when they began to apply their knowledge. 60's...? OK. 70's? Maybe... It's been suggested that Nailheads had 3x(?) the swirl of some other brands. That's not intentional? When you look at castings of all makes, you can kinda see what they were thinking, sort of. Not so important to dispute when they knew what, more important to understand 2 very distinct corporate realities. The engineer is not the decision maker, and automakers go with a design for a very long time. Accountants and foundry/production limitations win every time over the engineer. I would have to assume that at a certain point it is asked, "does it meet goals... is it below budget, will it sell, make it past warranty, become obsolete?" I don't this is ever asked, "are we giving the consumer the extent of our engineering capabilities?" Engineers work for the Co. to meet their profit goals, not the consumer. Their goals are different from yours. I think we've all seen 4v and ohc 60's prototypes. They started implementing more tumble/swirl when they changed from carbs to injection, because it was necessary. Tech school books from the 80's (not Hotrod or Vizard) focusing on single cyl. test engines had nearly any aspect you could dream of proven already. The focus was largely to predict mathematically what came out the tailpipe, and mileage. Then model it. Power and torque are necessary, but seemingly not the focus of the OEM's. Think about this...there were backwoods guys (albeit very smart) building 700 hp sbc's a nearly couple of decades before the 245hp TPI mullet machine. Rules (and component strength) held those guys back. See any backwoods guys on the moon lately? Clear illustration of goals vs. resources here. I'm not claiming to be any kind of expert, but I've learned enough to believe that what's known has been known for longer than most would think. Happy Black Friday.
Chris's information is excellent. I would like to add that I've read one thing that is slightly different, but I have not verified. If I happen upon a printed reference I will share it, otherwise please take with a grain of salt. Do your own research. I think I may have offered this before on a different thread, so forgive me if repeating, My understanding is that the clearances required for 2618 are more for reasons that the lack of silicon makes the piston more apt to scuffing, and that expansion is more related to section thickness and operating temps. I've heard that the coefficient of expansion is similar between alloys, but to me it's trivial to spend time looking this stuff up as my build strategies negate those risks. I'll venture to say that, and I only really skimmed both, the nomenclature Chris shared seems to be written from an engineering perspective. The Autotec info seems to be marketing speak with engineering in mind. Please consider that. I have gotten away with crazy stuff using 4032 on my own projects. I never suggest that for others. The difference of a couple hundred $$ is not worth the risk when it's someone else's. 2618, build it loose.
It's not, it's just a copy/paste of http://en.wikipedia.org/wiki/Hypereutectic_piston so you'd have to see the references cited. Devon
Having spent some time in the industry as a gearhead with an engineering background and having design responsibility here and there for twenty years or so, I concur. Every project is a battle between function and cost. The problem is that marketing may have a different focus about what the definition of function might be. Value = Function/Cost. Cost goes up, value goes down and vice versa. If you ask me, Buick excelled with their engine programs. Crying "foul" for Buick's years of work compared to what we've learned since then seems laughable as far as I'm concerned. They got the job done well. We're the ones who pushed and are pushing things past design intent. Devon
Absolutely, I guess I could have inferred the same thing without so many words ou:. You know why I wrote what I wrote. I have a similar background... less in design, but management, process, and marketing. I can't quite speak from your perspective, merely suggest things. It truly takes a team to get stuff to market. My point in comparing piston literature was not to critique the sources, but who reads it and how consumer decisions are made. I should have more directly pointed out that marketing CAN be hyperbole or propaganda. What's obvious to Engineering can go right on by the consumer. When comparing the consumer to a shop, can you guess which mindset their respective info's comes from. Consumers aren't often in the position to seek out or access technical info. Internet is making everyone a pro. Consumer reads, "It CAN be done, I should get this". Shop says, "I wouldn't suggest that". Different perspectives. Notice how both in comparing sources of literature, as well as sharing info on a head porting thread, we are all saying nearly the same things? The subtleties and distinctions can have a fairly profound interpretation. Here's a bad grammar example; I helped my uncle, Jack, off a horse...:grin:uzzled::bla: Good night.
You probably talked to Scotty when these first came out before their tech line knew the potential of their own pistons or more than likely weren't familiar with how BBBs make power. If you notice this quote in the ad; "Keeping in mind these pistons were originally designed for about 600 Horsepower. In Small Block applications, we have customers that frequently fine tune engines that yield 850+ Horsepower with a bit of Super Charger boost." "Designed for about 600 HP in a small block applications", Not very good grammar but it does say "small block" app. and "with a bit of super charger boost" that being said and considering we're talking BB I would think those would be good for at least 800 HP of BB power without the addition of boost that the sb needed to get to the 850 level. We know that BBs will naturally make more power WITHOUT BOOST because more cubes make more power without trying also the more air and fuel you stuff in a cylinder the more power is created, in a BB air pumps case they pull more A/F in naturally that will make more power.(blah, blah, blah) So I think those pistons would be fine for making up to 800 HP N/A in a BB application. If the engine would see lots of boost or lots of nitrous then the 2618 alloy would be the way to go. If you read the data on the alloys you posted you would see I am probably right. :idea2: It is probably time to re-visit Scotty's AutoTec pistons for a N/A 455 build over 600 HP, I think @ that 650 level those would of been the way to go if it was an N/A app., and the way they are customizable for the same price is pretty dam awesome if you ask me; "Bore, Ring Pack, and Compression Distance changes can be made to any shelf part at no extra charge. Meaning that if you do not see your application listed in the guide, we can make what you need without charging a custom price. Every part is made with same high quality machines and tools as our RaceTec line including diamond turned ring grooves, and skirts. Not to mention our parts are 100% made in the USA." In a BBB 455 non-jock strap N/A build I think these pistons would break the block before they experienced a failure.:Brow: Derek
One can put a piston in their engine and it will likely live, I've gotten away with it. This is for the whole board, not anyone specific. A shop will never suggest that logic. The possibility of a mishap with destructive results is not worth saving a couple of $100's from the shop's perspective. Remember, the shop isn't supervising the engine once it leaves. All pistons can handle much, much more power than "rated". The materials are chosen to handle mishaps of combustion at full stress and temp levels, not just survive with proper tuning. You'll likely make them work just fine. A shop would possibly hand you your parts back and bid you adieu.:laugh: The newer designs of pistons are better, yes. Many of the 'ol TRW's were copies of the 60's Pontiac piston. Old designs were some times chosen for production ease. AFAIK, 4032 is real close to VMS-75, the old TRW forged alloy. Still more brittle than low silicon alloys. Regardless of Autotec's rec's, other mfr's using that material will suggest differently. This is what I mean by marketing hype. Fairly meaningless statement, now hyperbole. Should read, "We strive to maximize our profits". This is not MY propaganda, standard shop procedure. Lets look at each claim; So, if I have a 300k live tooling lathe for cutting pistons, am I to buy another one to cut the different alloy? No. They only keep enough machines to keep the jobs running steady. Spindles not turning are losing $$. Do they use the cheaper machines to make the cheaper pistons? Not likely. Oooh, diamond turned. Love than one...I've even seen "reflects more heat back into the chamber". BS. Could be true, but not the reason used. Diamond tipped tools are used when the goal is to make 10's of 1000's of parts, changing the insert every few months, rather than weekly. Divide a $100 insert into that # for your cost per part. Coated carbide-$25 ea. @ 2 per week. Even coated carbides struggle with failure from the aluminum sticking, or a shock from an inclusion. Once that thin layer comes off (thermal shock) or chips away, the way it peels a chip from the workpiece becomes inconsistent. The operator will then start chasing the wear offsets on the machine around until they notice something obvious like an incorrect or rough feature like a radius. Oops. Now you have some scrap to go through. With a diamond, an operator might not move an offset for weeks, if only to get the machine past thermal instability from start up. They will go an entire production run and not move more than a few 10'ths. If you get sticking, like from not maintaining coolant, simply push the feed rate 20% higher and the aluminum will come right off, with less chance of taking some of the insert with it. Kinda like the difference between different piston alloys and their limitations, tooling inserts are sometimes chosen for how they handle mishaps. Marketing hype at it's finest right here folk.
