Sean this is in no way a jab at you, but Jim Burek dyno numbers are a joke, as are his flow numbers. Not saying said engine isn't or wasn't powerful but using Jim's numbers as a standard isn't fitting
Well, not sure why you're counting out adding cubes to get to that that power range? Either you buy an expensive turbo kit for not sure how much but lets say $2,000 by the time its installed to run on a tired over 40 year old factory engine. Or that $$ can be spent on a stroker build and make that much power without the turbo kit and have a new engine that won't crap out from to many full boost launches because its an over 40 year old bottom end.(I know when I turned 40 I didn't want to run for very long either, LOL) Do a pump gas friendly 500 HP 9:1 stroker and then eventually add the turbo for even more fun. Adding cubes even 20 more would help to bring the power range down to a more streetable RPM while increasing low end torque, typically down where the sbb likes to run, win, win. There are even more advantages but I have to be somewhere and have to go now. Derek
You can get away with a higher DCR when higher rpms and deeper gears are involved, as well as load applied to the engine is beginning at a higher rpm. Both the load to the engine being reduced and the faster sweep across the rpm range add X and Y factors to the threshold of DCR when considering pump fuel (load reduced by gearing as well as time divided to each cylinder). You should now start to see a trend as to what one can get away with and new metrics can be used to determine suitability of pump fuel. There's plenty more, but one can see how this opens up some doors. Swirl and other mixture motions also factor in. Now we come full circle to previous debates. The remaining questions being 'how much of any attribute is used to influence the goal?' and 'what factors are cooperative vs. counterproductive?' Any engine might be able to rev higher than the port or MCSA would suggest, it just takes something extra to get it to continue to make good power.
I agree that there are some questionable issues with the Jim B dyno tests... The engine we tested supposedly made 551 HP and then later made 440 HP and then back up to 530 HP with no major changes. Did I waste my money dyno testing, maybe but at time I did not know the issues with Jim.
Holly crap!! Thanks for pointing that out. I don't think there is anywhere on the planet that the barometer drops that low! No wonder those numbers seemed very high to me, I didn't read the fine print! I think the lowest the barometer goes here on planet earth is high 28s, 23.70 is probably not suited for life? I had to know; Lowest air pressure ever recorded: 25.63"; in the eye of Typhoon Tip over the Pacific Ocean (October 12, 1979) Highest air pressure ever recorded: 32.06"; at Tosontsengel, Mongolia (December 19, 2001) Lowest average humidity: 0.03%; South Pole, Antarctica Source: NOAA's National Climatic Data Center http://www.ncdc.noaa.gov/oa/ncdc.html Want More Records and other fun weather facts See this Site. http://www.keno.org/vws/weather_records_... They must of dynoed that engine in the eye of an even more devastating typhoon than the one in '79!! :laugh: Hilarious! What a waste of time and $$ making bogus numbers, they can't even be fixed because the real barometer readings on the day of the pull wasn't recorded. Unless as long as the day and time is on the dyno sheet then the real numbers can be put in for the REAL HP numbers, well as real as this unrepeatable dyno shop can get? o No: I hope this piece of dyno sheet doesn't make it in your book Sean. I'm sure it won't. :TU: Should of posted with that dyno sheet , for entertainment purposes only , cause I don't care who you are, that's funny. Derek
Seems to me like there were some anomalies with the correction factor calculations. Maybe it was his software or dyno? A typo or oversight? To be fair, it may be a bit presumptuous to insinuate dishonest intentions without knowing all the facts.
Yeah, actually you should put this dyno sheet in your book as a warning to people paying for their engine to be dynoed as something to be aware of how a dyno can be fudged. May not want to mention the shop that did the pull though for legal reasons, unless you being north of the border makes that not matter? I know this wasn't you Sean or even that you were aware of how that would sway the numbers so greatly. Its to bad some people can't be truthful and let the numbers drop where they will. Is it the same guy with the 550 HP 8:1 sbb 355 that never seen the track that got sold from the original owner before he ran it in a car? The one that they claimed to develop a coolant leak on the dyno that kept needing to be fixed? That guy? Derek
I wholeheartedly agree. The dynamics are so wide and varied, making it very difficult to map something out or measure 'on paper' that would reflect a realistic outcome without actual real world testing to back it all up. I believe much of this has to do with unknown circumstances that occur within the engine unless you had a heck of a lot of experience dealing with various changes made, and even then it's a 'best guess' until your tires hit the pavement, though a pretty close guesstimate could be made from such an individual(s). A few things we know for certain are: -Power is gained by the amount of air and fuel moving through an engine, whether it be from higher rpms, increased displacement, or forced induction. -This is affected by the techniques involved influencing its movement -Circumstances surrounding the engine itself affect overall performance of the vehicle -Realistic goals for intended application(s) of any engine or vehicle to determine limitations placed upon it (or innately incidental) *should* produce relatively predictable outcomes.
I was just trying to be fair, but I guess I didn't know the whole story. I suppose then it's fitting to warn others. As Derek pointed out, those numbers definitely appear to be fudged. Or maybe it was for a 455 and not a 350? That would be more believable, if not for the bogus barometer figure. That's the dead giveaway there. Sheesh.
This was the engine was was claimed to have made 551 HP at 10:1 compression and then was sold to a fellow who is not into drag racing. He has the engine healthy and burning rubber in a 70s regal street car. As far as I know it has been reliable over the years, regardless of the actual HP numbers this is a nice engine. Jim B did complete a lot of really good engines, however when he tried to step up to help Buick people get the "Bulldog" 455 blocks he ended up involved in a HUGE fiasco that led to him going out of business. Jim B seemed to have good intentions and good Buick knowledge and reputation in the early years however by the end his reputation was screwed and he was putting up some bad engines due to a various amount of reasons which involved stress and who knows what else. I know of a few guys who got the Bulldog blocks, one of which broke in half.. many others ended up loosing the money. I do not think that Jim B meant to screw people around but when people gave HUGE deposits to him so that he could get them a Bulldog block and then "Bradshaw" the guy behind Bulldog who was a real con artist never really made good on the promises of all the blocks even after taking all the deposits from Jim B. So after going through all that and Jim trying to pay people back the deposit money he went under... All accounts from old school Buick guys say that Jim B was a far different guy in the early years then how he was perceived at the end... I could be wrong but this was the impression I have gotten.
I believe that is corrected from sea level pressures as where I live at 6500ft elevation is around 80kPa = 800mb = 23.6 inHg. The weather service and such normalize the atmospheric pressure relative to sea level to be more comparable location to location (and for aircraft). El Paso should be around 25inHg normally, so being hot, etc, it could have been 23.7, though even personally it sounds pretty extreme for that elevation.
Yeah, that's the same engine, I just didn't remember the exact compression but I still think they claimed 8:1 static and 551 HP. WAY long thread with an anti-climatic ending, I would suggest not wasting time reading that one like I did. I'm sure the engine was a decent piece but in reality using the shenanigans that was on the dyno sheet you posted that engine probably made around 200 HP less than what was actually posted in that thread. o No: That's to bad he thought he had to resort to scamming because he got scammed. I would of NEVER been the middle man for something like that unless I had my $$ and hands in the casting process. If the Bulldog guy wasn't such a greedy db and stuck with it he probably could of turned it around and still be in business today. I think Bulldog is still around but under different management/ownership, I believe the Cadillac Bulldog heads are still available IIRC? o No: I guess desperate people do desperate things? Derek
I still don't think it's fair to pass judgement not knowing the whole story or circumstances surrounding why things happened the way they did. Certainly not for anyone who's never had to go through the same things. It's always easy to say what one would have done had one been in that situation, but you never truly know how you'd react until it happened to you. Nothing can change the fact that JB is a top notch Buick builder, no matter what happened. He was the contributor to that article about head porting, and even if those flow numbers were embellished, it was still good work and a good guide. I suppose when someone's lost money, everything he did is going to be crap, so there won't be any saving grace with those people--and understandably so--but the truth is the truth. Didn't those heads make around 390 hp on a Buick 350 and a moderate flat tappet Poston cam/intake? Or was that embellished too?
Take it for what you will, but I ran some numbers on the dyno sim using the numbers I have that give a sneak peek into what a set of aluminum heads are capable of. *disclaimer: No implications intended here for any existing or future products are contained herein. For representation purposes only. Specs for engine are as follows: 355 CID Buick 350 using a high flow single plane intake, single 1000 CFM carb, large stepped-tube race headers, 12:1 static compression, formerly represented (simple, non-tweaked) solid roller cam (.600/.600 I/E lift, 302/302 I/E @.006 and 248/248 I/E @.050 duration with 110/108 LSA/ICL) using aluminum heads with standard 1.92/1.55 I/E "Stage 1" valves (head CFM confidential). Averaged power ratings between .006 and .050 show 496 ft. lbs. @5750 RPM with 643 hp @7500 RPM showing between 104-109% VE at peaks. Potential is there.
My "703"hp Burek engine ran 95mph to the 1/8, more like 550hp, then ate it's self after 3passes and 100miles, paid for $1500 for porting that didn't happen, paid for new heads and were given used ones, paid for new pistons and got used ones ,paid for Billet mains which were installed out of order, so there was no where to bolt pickup too,the list goes on, an on, an on nothing top notch about him or his work sorry. Not trying to dredge up the past and something that has beaten to death and even made a sticky but....
No problem! I also looked up the NOAA's "lowest Barometer ever recorded". this thing must have been tested on the top of mount Everest in the middle of a Hurricane! Correction factors are there for a purpose... To compare against a standard. When I do dyno testing I hate to see a correction factor that is greater than 1.01. I do not like to see a multipier involved in any way! The Dyno cell that I test in cannot compensate for Barometric conditions, but I can set my combustion air conditions. I always use SAE correction factors.
