... Ok I gotta go now. It has become clear my boots are not tall enough to accommodate all the bovine excrement filling this thread. lol! Gary
If you do plug it up, TA does have the freeze plugs to do it, as stated before they're 3/4 freeze plugs. The take next to nothing to install and no chips to worry. Gary I've heard that 195 thermostat state metion is true, that's why newer cars run that. Local car quest owner has late 60s impala and says he prefers 205* running temp. Josh
My apologies to the original poster of the thread! Thanks for picking apart my posts Gary :grin: I'll take yours as a compliment. I guess one could choose to disregard some people's offerings and never learn anything. I learn stuff here all the time. I suppose if everyone here was named Kaase, Roush, Jenkins, or Smokey (wait, there is one of those here...), then information sharing at this dinner table would have a hefty price? I guess I didn't need to carefully engineer my 12:1 tunnel-rammed pump-gas engines to survive on 92 octane 20+ years ago. All I had to do was simply buy higher octane fuel! Why didn't I think of that, sheesh. :spank: Maybe they sell 98 octane Sunoco everywhere. Forget the price of the old Turbo Blue, gas is cheap! I would hardly be the first to do those, and I can assure you...EGR would be a mistake there. It's not impossible to use as much as 270*@ .050" in a 6.6 liter engine and have a tame enough idle @ 950 to still use power brakes. Easy? No. EGR? No. [Referring to inlet air temp eventually being a limiter when increasing the cylinder pressure curve well beyond a factory stock engine] Inlet air temperature adds linearly to the temperature at all phases of combustion, directly bringing the charge closer to the autoignition temperature. I'd like to see this proven wrong... You and I can both describe paradigms that support our respective positions and cite real world examples built. (pointless and non-productive) We could even throw formulas and SAE papers at each other in a nerd-style-hissy-fight, but I prefer to learn from people and apply their experiences. I find it completely senseless to say others' accomplishments are "BS", only because they haven't tried the same thing and made it work...yet. I would hardly waste anyone's time offering something up I haven't personally done. I'm encouraging others to go just a bit beyond what they accept as popular opinion and ask questions like, "what will it take to...?". I suppose something that helped me along my own learning curve was to not accept the limitations imposed by laymen or popular opinion. It also helped to learn from those willing to teach, and remain humble. Didn't mean to strike a nerve, but nothing I've previously stated is new ground, it had to be learned somewhere. Hmmmm. Sorry Gary, this is like arguing ship's highest ranking officer to an iceberg or lighthouse. I'm actually looking forward to what can be learned from your well thought out and factory blueprint optimized buildup. I'm also open to learning from any other beyond-the-norm builds you have done. Of course, I don't expect you to give up all the details or any other competitive edge. Once again, sorry for the major derail!
And yes...heated air and warmer coolant temps help mild engines. Ones that do not come close to the auto-ignition threshholds flirted with when exceeding normally accepted dynamic compression ratios, cylinder pressure curves, etc. I can understand why one wouldn't want to add the many other factors to a dynamic ratio spreadsheet. The formulas become quite involved and require too many hard to verify criteria for the casual enthusiast. Good general starting point. Definitely has merit.
We go from blocking heat crossover to whatever all this is. If you want to block the crossover be prepared to give the carb a bigger shot of gas from the carb to keep it running right you will also have to up the jets some since no heat means No atomization of the gas before it hits the cylinder. You would do better running the TA intake since the stock one will hold a ton of heat in it. Put on a wood or phelolic spacer to help with heat. I use the wood one and the Q-jet is not going to give you the adjustability of the off idle running that a Holley would give you. Why do you think Demko is having so much trouble with bogging with his intake, blocked crossover and not enough of a pump shot to cover it up. That blocked heat crossover is more for race applications where you are going to need cooler intake charge. This is not for a stock engine. you want to block it drill a hole in it to let some heat in and run a TA intake and that will run cooler. you guys are putting WAY too much into this. How much extra horse you think you're getting from this.
Newer cars have micro processor controlled fuel injection and ignition along with knock sensors and the ability to retard ignition timing to protect the engine from detonation. If you have a bone stock engine and plan to drive it like Miss Daisey, sure, run it at 205*. But if you plan on driving it like you stole it, make sure everything else is right and it doesn't detonate. I prefer no more than 190* at most. My engine runs right at 180*.
My posts were relevant to the OP's question and pertain to mild street machines, hardly pointless and non-productive. I do not have to manufacture imaginary scenarios in which the EGR would be pointless in order to prove a point that isn't even relevant to this discussion. This is the reason I 'picked apart' your thread. You can run 12:1 compression on 87 octane with the proper tuning, combustion chamber prep and late enough IVC point. We both know this. I'm not going to argue about your claims, since there is no way to prove or disprove any of it. Is it relevant to the OP's question? I don't think so. I was trying to prevent the derailing of this thread by steering the subject back on track and offering up some benefits to leaving the engine in tact, instead of jumping on the heat crossover block bandwagon. Clearly the Buick engineers did not know what they were doing, and it's up to heroes like you to magically transform bored and stroked big blocks into gas sipping commuters (which all of course last longer than any OEM design and get 4 cylinder gas mileage , which again has nothing to do with the OP's question. The only real thing you were trying to do here is derail my suggestions and factual information, and could only do so by offering up scenarios that have nothing to do with what's being discussed here. If you want to learn from my accomplishments, all you have to do is re-read my posts on this forum. Yes we all share knowledge and learn from each other. That's the beauty of this website! I try to offer up tips to real world average people with average building and tuning skills, so that the outcome isn't dependent on guru tuning skillz in order to achieve accomplishments that deserve to be in the Guinness book of World records. Reminding others of real world expectations within normal driving conditions that are often overlooked or forgotten in the quagmire of performance upgrades/suggestions can be a bit daunting within a racing enthusiast environment, but hey I try. I believe the discussion was about a stock engine. Care to continue the derailing? Gary
You can calculate Effective Compression using dynamic and VE to get a decent idea of where those thresholds are at any given RPM, and base the octane requirement on the highest ECR (Effective Compression Ratio) @210*-215*, no matter which cam, head, static compression ratio, or air flow dynamic is used. Instead of using a computer to control it all, you have to err conservatively on which octane requirement would be needed under the most severe duress and use that. For a stock engine, a static compression ratio can be calculated to be used with a particular grade of fuel (considering refinery and fuel quality variances), which would work very well with the factory EGR valve. Even larger cams with good intake vacuum can be used this way. It would, of course, require leaving the heat crossover in tact, which seems to be curiously taboo to some people. Perhaps instead of all the calculations, it would be simpler to omit it and use an aluminum intake along with a 160* thermostat and run everything cold... simpler, but not as efficient. So who then is taking the easier way out of this? Gary
So many people still misunderstand what dynamic and effective compression ratios are (not to mention pretty much everything else). I may purposefully ask questions elsewhere on other threads (Big Block forum, for example), to put out thoughts on the table that others may either be too timid to ask, or didn't think to ask, knowing full well the answer myself. This may make me appear as a 'layman' or inexperienced, when my goal is to stimulate thought and/or discussion. Often times though, things wind up getting offtrack and it makes me wonder if my efforts are really all that helpful at all. So with that thought, I'll retreat back into my observatory and continue watching the same old tired cliche's, stereotypes, and obstinate mindsets continue on their merry way. Good Luck. (P.S.-Tony, I apologize.) Gary
Yep, let's continue derailing. It is a derailment because you took things you haven't seen yet that are very valid to the OP's potential direction and responded with what looks like a personal attack. Plenty of engines with 30-40 year old design have proven 500k-1M miles. This is nothing new or even made possible by "new age tech". The few changes aren't in passenger cars because of planned obsolescence. Who would need a new car every 2 years if they lasted forever? Not superhero territory. Try doing a few with that in mind and you'll see. I don't think the BBB in this forum getting good highway mpg's is too far fetched either. Any competitive motorsport that follows rules requires pushing the envelope far beyond the popular accepted norm. Nothing I've stated previously is new ground. If you want to disagree with me based on theory and not having actually tried it, it's as simple as making the decision to commit to a goal and doing what it takes to get there. You don't see many people pushing limits and sharing with the public because they aren't being paid to. Based on my experience in manufacturing, marketing, and as executive leads me to believe that tactics like lower tension rings, hotter running temps, computer control, or any relevant modern changes have much more to do with having a 100k maintenance schedule and warranty than a little bit of efficiency squeaking out a few mpg. Planned obsolescence is still a major component of the corporate directives. Everything I've studied on the engineering end of gasoline engines including emissions, mileage, and power output suggest to me that STUDENTS are being taught things already proven that the OEM's don't incorporate for quite some time. Engineers aren't the ones making the big decisions. Their goals aren't what the customer thinks they are. They are capable of far more than what's being marketed. As far as the "no EGR bandwagon"...I support keeping it under certain circumstances. It has it's place. Regarding octane tolerance, students more than 25 years ago could come up with the formulas to calculate various limits based on many more parameters than DCR would, just as an example. Temperatures, mixture motion, effects of incandescence, proportions and scales (such as surface to volume ratios) and LOAD (such as sweep rate) are MAJOR contributors to the overall formula. I will agree that it became pointless to math all that out for a simple "hot rod build". Guess what happens when you do...you learn something. Like you Gary, I came up with a "line" and use some of the other metrics to tip the scales positive or negative. Again, good starting point. Much more useful than buying the cam at the bottom of the page or asking the guy at the counter. I'll even refrain from personal stabs and suggest that we are probably wired similar, but come from different learning experiences. Although I'll readily dispute tech comments I can support with firsthand knowledge, it is for the purpose of benefiting the forum community! I don't believe I've ever taken personal jabs at anyone publicly. Believe it or not, I support a large percent of what is offered here. [Gary, I do the same thing with some questions. I already know the answer to them and the goal is to stimulate conversation. I left this post hanging for a while and didn't see your last post. The intent wasn't a hostile reply. I'm not here to do anything more than participate and contribute to a tech-minded community using past experiences and education. I still do a few builds on the side. A 4.5" Pontiac stroker just came up. I am aware that I can be abrasive and that the subjects can rub elbows...even egos. No harm intended] I can say with absolute certainty that there's enough talent on any of these forums that anything I've achieved (and I've not fully shared those) is well within reach.
I still want to see the parameters of a built 12.1 comp run on 87 octane. I also want someone to explain to me why I have a Corolla XRS that has 11.1 comp that Cannot run on 87 octane and must have at least 91 octane for that motor. Will it run on 87, probably but 91 octane is required. Matter of fact I tried to run it on the middle grade and eventually the check engine lit came on after 65,000 miles and I needed to replace both oxygen sensors. I also found out that BP premium gave me the best gas mileage and kept the check engine light off the longest until I eventually had to have it fixed. Now I have 175,000 miles on it and I run only premium gas in it. The engine has variable cam timing and turns 8000 rpm and I run nothing but Mobile 1 synthetic. So tell me how to run 12.1 comp with 87 octane. Tell me Ahhh another thread that has gone from a simple question into another story, gotta love it right Buick guys lol. maybe a new thread should be started called "Thoughts" to get your mind going. lol Any 500 horse 350's built over the winter or has another one past with out any. I have built several of them now just waiting for a ride to put them in. Oh BTW I have a Garmin Mechanic hooked up to my computer that relays information to my Garmin that tells me timing and engine temp and such.The engine is constantly pegged at 185* to 187* and if it gets to 195 the fan turns on for the radiator. so it looks like to me the engine likes to run at 185 for best running temps. The timing varies from 8* to 32* depending on where the gas pedal is at. So 210 on your Buick motor is too much go with a 185 therm stat.
Sarcasm fully intended! I couldn't think of a different automotive related way of saying "I bet Neil Armstrong gets bitched at for putting the toilet paper roll on the wrong way!" OP, you could try to block the crossover, and if you don't like the way it runs or have difficulty tuning it you can always pull the core plugs and reconsider it if you do a full buildup.
Guy, it's all about cylinder pressure (or the lack thereof). With a late enough intake valve closing, the dynamic compression would be dropped way down so that a much higher static compression could be used. This isn't exactly the best way to build power, but it can be done. It was mainly to make a point of what is possible. You could also get an 8:1 compression engine to require 93 octane using the same method, only reversed. Understanding dynamic compression is the first step, then volumetric efficiency at varying RPMs (and scavenging) usually increases the cylinder fill which results in an "effective compression" which, when coupled with timing and engine temperature, along with fuel quality, atmospheric conditions, elevation, etc. will result in the octane required. There's more to it than that, but that's the simple explanation. I'm sure my evil twin will chime in to elaborate if he feels like it. As far as the engine running at 210*, it has to be incorporated into the build. Applying it to YOUR combination may very well be a mismatch, so yours would be best running a bit cooler, since your engine is pretty far from stock and has different needs. As long as it doesn't dip too far below 180*, the wear characteristics on the cylinder bores and pistons should be fine. There's a lot of opinions based on what temp your engine should run at, and we could be here all day discussing it. Gary
It's extremely difficult with any of these posts to ask about a singled out parameter..."what's best?" It depends on what you are trying to do! The big picture is a lot bigger than anyone can guess without a lifestory and dissertation so that contributors can quickly construct a paradigm based on where the mindset of the OP is coming from. My Doppelganger might assume things to be oriented around the stock of flavors of Buick and it's merits. I might assume a different direction is desired. Both are valid, if anything for sake of discussion. Generally speaking, removing one component of a factory installed system is a huge mistake. Guy, in the late 80's(?) the mechanical knock limit of 87 octane (blended at that time) was capped around 17:1? [IKR? :shock:] Factoring out the metrics in the formulae that you and I cannot quantify, but keeping in mind as positives and negatives, one can find a "line" for real world knock limits and work from there. There is no "25 step guide to running high compression on today's pump fuels" bible that's safe for everyone , but there is enough out there available to the enthusiasts of today to benefit their own real world builds. Take some peyote and a laptop out into the desert to go on your visionquest, it can take a while to really absorb it in enough to incorporate into your projects. Brush up on your math while your out there. I think having a good grasp of this concept along with airflow dynamics, and you can really utilize today's sim programs quickly and effectively. There's cheap and easy solutions to this nearly 40 year old problem. E85 comes to mind. So does boost (and everything that goes with that). Building one for yourself just to say you can do it is one thing. Giving the vehicle to a 19 year old kid and telling him to "always keep the coolant temp 120* or less for full throttle and don't hot-lap it" is really asking for a basket full of broken parts. Or maybe use a tad bit of realism and know what limits you can push and when so you can have some fun without so much worry. {To add to the concept of knowing your cylinder pressure "curve"... fully understanding temps, load and time spent will really add a dimension to this]
I guess if you drop the cylinder so low that the DCR drops a mile, yeah you would have to up the compression to make up the difference. I get that but why, just because you can, is there a benefit. The Corolla runs at 187 constantly, if it hits 195 fan turns on. This is a 2005 car but I was equating that to the Buick engine in the sense since the modern car likes to be at 185 The older engine should run well there too. Taking an engine up over 200 you are just asking for trouble. The potential to overheat rises quickly and this heat is hard to cool down. Actually, I have had my best runs with the engine cooling off to 150* then starting back to staging, by the time you do the burn out and go up to the light, you are at 185 but the intake is not that hot yet. This is why you would block that heat from the intake. I would not block the heat unless I was looking to extract as much HP as I can from the motor. I you run the stock intake eventually it will get warm enough to help with the fuel but then at that point you may have too much fuel going in the engine and will have to back off the jetting. So at this point it would be better to run the Alum intake with the crossover blocked. The Alum will stay cooler will not soak up heat like the heavy stock intake and you will be able to get the jetting and the squirters right with the carb. See, this is why the Holley or similar carb would work better with this combo. Looks like I need to get some peyote and my laptop along with my math book. Should I graph it also with two points on the scale and give a final equation. Wait a minute I am seeing colors from the peyote. Can't compute It's all about the math.
