OK Gary and anyone else that wants to participate. Help me with a blueprint for a stock engine. So I run a stock untouched 350 and do a 200 mile round trip down interstate towards Portland and back which is fairly flat and do the speed limit which is 60 and 70 mph so I can check gas mileage. Then take it to Pacific raceway and get a good baseline 1/4 mile. Take the engine out and get a baseline on the dyno. Do a rebuild as you described, all bearing clearances to spec, resize rods with new rod bolts and insure they are all the same length, side clearance and so on... Use the Sealed Power 340P cast pistons which should have tight piston to wall clearance. Here is where I would like to deviate from the norm. I like using BWE piston rings with the ZG second rings. The leak down test shows almost zero. We get an increase of 2 to 3 inches of crankcase vacuum on our engines that have 3 stages of oil scavenging. (Dry Sump Systems) Use the Federal Mogul CS647 cam with "camsaver" hydraulic lifters. Use a static compression ratio of 10:1 for a DCR of 7.6:1 If everything so far meets the guidelines of blueprinting a stock engine, my question is: What am I allowed to do to the heads and still be within these guidelines? After completion, the engine gets another dyno run, 1/4 mile run and interstate run to for comparison to the baseline numbers.
Man im sorry, but it takes airflow to make hp and the stock cam can only support so much, if your the type thats satisfied with 325hp then more power to you . But if you wanna make real power NA its gotta have a cam . I'll agree throwing a 240 cam in a dual.plane low rpm , low comp setup isn't to bright but there is nothing wrong with putting an upgraded stick in your 350 rebuild. And using the super stock reference in defense of cam size isnt a fair comparison, as mentioned above them cams are super aggressive, they run more compression,more gear, more stall, tricked out trannys etc. A far cry from what the guy in his garage whips up to take to cruise ins and an occasional blast down the strip dont you agree?
I agree. I'm simply trying to stay within the theme of this thread. It would be interesting to see how much gain there would be in just doing a really good stock rebuild with some cleanup work. It would also be good to know what the real baseline power is for stock.
Derek has found on my engine the the block was about .023 taller then blueprint and the other side was even taller. Factory head gaskets for 70 are .020 steel. Felpro gaskets are .043 crushed. Getting piston as close to zero deck has advantages. H522p silvolite hyperutectic pistons are 1.855 comp height. That's .020 taller then 340p and has valve recessions.
Those 4 valve relieves in the H522CP pistons eliminate most of the outer ring of the piston top. The 340P has more surface area at the top by far and less volume in the dish. I'd rather deck the block a little more and use the 340P .020" in the hole with the Felpro gasket Thanks for looking.
Basic massaging techniques. As little material removed as possible while cleaning up casting imperfections on intake and exhaust (as well as bowl cleanup), and polish the exhaust. Stock intake and exhaust manifolds the same, only polish the exhaust manifolds. Polish the head combustion chambers, and put SCR @ 10.21 (or as close to) for 7.75:1 DCR @ 71* IVC point. As the engine wears in, the stock timing chain will 'stretch' (wear in) and lose 2*-3* making final 'main sequence' engine life valve timing at around 73* give or take, putting DCR at around 7.6:1. Gary
I myself plan on building such an engine for myself, using similar techniques (and more) that have already been mentioned/suggested in this thread (and elsewhere regarding this topic). I plan on documenting every step of the way, including dyno and track results to back up the street testimonies, and videos/pics. I'll even show everyone how to really drive a car. This engine won't be the fastest Buick 350 ever built, but it will once and for all show what a bluebrinted STOCK Buick 350 can do. I am confident that it will be a real eye opener and mind changer. Even the knuckle draggers won't be able to argue with timeslips and dyno runs. As the engine is being driven every day, I'll post periodic updates on mileage and performance differences over the years. Probably every 50,000 or so miles, up until the engine starts to feel tired and then I'll remove the camshaft and take multiple detailed pictures, along with the total miles that were accumulated on it. I plan on being here a while, though my input will become more limited, if not stop altogether. I'm fed up with stupid people. There I said it. I tried to be nice, and generally I am, but this time, I have to let the truth be known. You can lead them to knowledge, but you can't make them think. Maybe there will be others out there who will be able to use this knowledge at some point. Gary
Gary I read through all the comments again on this and the other threads and I don't take it as non-supportive to your cause. For the most part there is agreement and where there isn't they are simply saying that the blueprinted stock type engine isn't for them especially if their business depends on it. We have all read some nasty string of posts on other threads that eventually got shut down but this isn't like that. Besides there are many readers on at any one time that are taking in what you are saying without posting any replies and will find some wisdom in it. We need both ends of the Build spectrum posted to help everyone see what is available in order to make an educated decision. You are treading in somewhat new territory and as usually many want to see proof. Paul
A couple of nudges to this question and you can answer it yourself fairly easily. Forget CFM for a minute, when you flow factory unmodified heads they aren't that great. Mild porting increases the velocity and stabilizes the port,sort of the opposite of urban myth. Forget the cams for a minute too. They have influence to the powerband, and really become the relationship to the cylinder demand and the door to it being open, meaning their influence could vary greatly depending on the combination. Torque peak follows when the intake tract reaches a certain velocity (range). If you enlarged the MCSA, you would be very predictably raising the rpm of peak torque. You could do that without much loss of velocity, because the rest of the work you are doing speeds up the port considerably. This also means you would likely pick up torque and drive-ability below peak torque, at least in cases I've worked with. One way of saying that is that even if peak torque rpm was raised, there would still be more torque below that than stock, using that strategy. Intake runner length would have significant influence below peak torque, much more so than the cam duration (to a point) and is a current OEM strategy. When you don't see improvements is when you "open the door too wide or for too long" and lose the pressure differential between the cylinder and the intake tract... over-cam. A single plane intake on a mild engine would kill the velocity and not draw through the venturii as well, it's about the overall package. I'm seeing 2 schools of thought in these threads; 1. The factory put out a really good working engine. Blindly throwing a cam at it might reverse an enormous amount of engineering. Mild porting and blueprinting would really make this engine shine. The cam would work VERY well with a blueprinted version. I agree! I've done some of this, it works! 2. If you are going to do that much to it why waste your time with factory parts, esp. when you can make much greater improvements yet by being in control of the specs and engineering. I agree! I've done a lot of this, it really works! My personal opinion of the Buick 350 is that you could easily make these equal to modern ls engines for streetable builds, based on the bore/stroke - heads. Get some #'s together and plug them into the readily available formulas and plan your build out! You guys have enough knowledge that you can probably get these things to do EXACTLY what you want them to do. Good luck.
Gary, I would love to see the results of a perfectly blueprinted 350. I agree many would be surprised. Your input is always appreciated by most on the board. If they don't care for what you say then they don't have to follow your advice. Never stop helping. I think the issue with these posts is we don't really know each other and can't tell when someone is joking. If we were talking on the phone then it would be easier to tell when someone's kidding. Just like texting, sometimes a typo can totally change the meaning.
That's me. I have a GS 455 (that I need to get going!), and a turbocharged 455 (that needs head gaskets, I think), and a GS 350 that was rear-ended by a large truck and needs a LOT of work! I think it would be neat to build it into a full tube chassis drag car with a turbocharged 350 in it, so I check out what's going on in the 350 threads. I'm being honest when I say good luck with that. Stupid is everywhere!
Gary, think about it...positive and thought provoking posts aren't going to be heralded and replied to nearly as much as the impact they leave deserves. The negativity stands out though! I'm not aiming this at ANY individual, just that it does (me too at times, I think). People unintentionally rub each other raw at times. Everyone here has different experiences, skills, and contributions. There are some that have way more than what they lead on and are trying to steer people through their learning curve, rather than give away their profession. We need to be thankful of anyone who chooses to contribute selflessly. :beer:beer
Lots of wise words here fellas. Thanks for the encouragement, and I apologize if I offended anyone. I pretty much know/knew what everyone's saying, I just got discouraged is all. It's nice to know I'm somewhat useful around here. I never expected (quite the contrary) anyone to embrace my idea(s) or even agree with me. All I wanted was to present an alternative point of view and encourage people to think. To see that it has even gotten this far is an accomplishment. In a nutshell, my objective is to maximize longevity while producing as much power and efficiency out of the engine as possible. It wouldn't even have to be the Federal Mogul CS647 cam, though it is a good foundation and any custom cam would need to be very similar to it...which is why unless you go roller, you might as well just stick with that cam, since a custom cam wouldn't really improve the engine much to warrant it, providing the engine was optimized around the camshaft. So I lean towards either the Federal Mogul CS647 cam, or a roller version of it. I'll most likely stick with the (much) less expensive flat tappet Federal Mogul cam, since it will be on par with a realistic street engine that anyone could put to use and not spend a fortune building it (though investing some money in a roller cam is wise--but not necessary when using the Federal Mogul cam--with an engine that lasts so long). Though there's a lot of Buick 350's still out there and can be had cheap, there will come a day when this isn't necessarily the case. The engines are a finite resource, and they will eventually get used up. Preservation of history and the wonderfully engineered machine that is the Buick 350 is a high priority for me. Gary
Think about it...the industrial versions of engines easily get close to a million miles in a fleet situation. Only slight differences in some materials, like valves for example, and better timing components. Low rpms help. I've pounded several ruthlessly every day for over 100k miles. The valve train wears out first (springs too). Keep the builds to a reasonable rpm range, warm them up before pounding on them.
Yessiree...which is why I was focusing the discussion on the valvetrain moreso than the rest, though getting everything else 'perfect' makes for a good foundation. :TU: The 'camsaver' hydraulic lifters from Crower should also help aid in this, along with lower RPM usage over the majority of the engine's life, since it is lower RPM that will wear out the camshaft/valvetrain more than 2000+ RPM ranges. Gary
do you have any info on this Gary. I assumed 5000 + rpm runs are what would create more wear then light "grandma" type driving.
Once they are warmed up there's very little wear, even at rpm. I remember seeing a wear graph from GM, related to bore wear and temperature, from the late 60's(?) . Isn't the GM durability test full throttle between peak torque and peak HP for ten million cycles? I can personally attest to using more than one personal vehicle to do Rep work and putting on over 100k miles, as well as teardown or refreshing. Much of my driving was across state and very intentionally on rural roads. I beat the living hell out of them as much as I thought I could get away with, every...single...day . Between 120k and 140k is where you could tell the difference in the way they ran from valvetrain wear. Full throttle between 4000 and 6200 rpm. 454 Chevy was one of them, so the valvetrain isn't the best. Beats being in a company Taurus 10+ hrs a day. Would this be the difference between a 120k life and a 300k life? Who knows.
I'm referring to the splash type oiling for the camshaft (lobes) on these engines, which is supplemented by the 'camsaver' lifters at lower RPMs, particularly below 2,000. This is why you rev a flat tappet cam past 2,000 RPM when breaking it in, so the camshaft gets plenty of oil on it from splash. Consistent driving below 2,000 RPM will wear the cam out more without the 'camsaver' lifters. It's also why excessive idling isn't recommended for these engines. While not 100% necessary, obviously, it would help with longevity. Though this scenario would be more prevalent with a 'highway' gear and/or overdrive trans, where the engine sees below 2,000 RPM for extended periods of time. Gary
so the methods(s) you are going to build your engine will be better and faster than how the nhra stockers build/blueprint their engines to the nth degree. food for thought for all, some of those nhra stockers make a living doing it. day in, day out. and they ain't stupid!
