CC57 Posted July 19, 2011 Author Report Share Posted July 19, 2011 Thanks Chase Link to comment Share on other sites More sharing options...
thumper Posted July 19, 2011 Report Share Posted July 19, 2011 Mr Bishop,are you related to the people with Bishop Engine Parts in Dallas? Link to comment Share on other sites More sharing options...
CC57 Posted July 19, 2011 Author Report Share Posted July 19, 2011 I enjoy and take in all aspects and welcome input from all perspectives: engineering, analytical perspective “based on experienced”, and just plain ‘ol common sense. But the one I look forward to most is the one that finally provides the resolution to the issue, whether it’s perceived or real. So I guess what I’m trying to say, is thank you all for your suggestions and contributions. Link to comment Share on other sites More sharing options...
jwmbishop Posted July 19, 2011 Report Share Posted July 19, 2011 Mr Bishop,are you related to the people with Bishop Engine Parts in Dallas? Not that I know of. I am originally from Southern Ca., was GM at Cylinder Head Service (the owner was a close friend of Bruce Crower and we used his dyno as well as worked on several projects including John Gates's funny car - he scaled down and moved the shop when I left in 95 to pursue current business), before that I was shift sup at McBurnie Coachcraft. The Bishop side of the family are originally from Wyoming. Link to comment Share on other sites More sharing options...
jwmbishop Posted July 19, 2011 Report Share Posted July 19, 2011 But the one I look forward to most is the one that finally provides the resolution to the issue, whether it’s perceived or real. Ain't that the truth. And usually the perception is just a matter of understanding what is actually happening vs what seems to be happening - for example we often interrelate volume and velocity when it comes to fluid dynamic when they are really very separate parts of the overall equation... this discussion being a prime example. If you look back at posts I made a few months back I was totally on board with the theory that the speed of the water gave it more time so advocated a restrictor to slow it down. so what changed? A protracted conversation with a very well qualified engineer who showed me with math (which is ALWAYS constant) exactly what was happening in not only cooling - but ANY heat transfer system - a\c included. Then asked me how could I possibly make a definitive evaluation using T value from only one location - not knowing BOTH low and high temps? Likened it to just relocating the temp guage to the radiator out and telling the driver 140 is the new norm! She kinda made me feel a little "duh" moment. - especially as I too have spent hours trying different restrictors and timing to control total temp! Especially given the goal is to make as much temp as possible (converting fuel to energy). Link to comment Share on other sites More sharing options...
KISS_Racing Posted July 20, 2011 Report Share Posted July 20, 2011 Mr Bishop, Thank you for your willingness to share. I was talking with my mentor Monday and he mentioned "never stop learning and never stop reading". He said many people think they know it all and are not open to learning knew things... <=== (Not pointing fingers just repeating what he said...) I don't always agree with advice I'm given, but do ask around to see if it floats... Mark Link to comment Share on other sites More sharing options...
jwmbishop Posted July 20, 2011 Report Share Posted July 20, 2011 Thanks. And I do apologise to you termite as it appears I am second guessing your well qualified crew chief - I would probably defend him if he were mine as well. And for the life of me I could not find the words that reduced that appearance significantly. just for clarity let me throw out there why I would push the temp up from a 190. the standard temp of 185 was designed years ago primarily as this is well below the boiling point of the coolant at the lowest pressure point (in above post I was bass ackward - heat at sea level to 210 no boil - take that up in elavation and boiling will start due to lower atmoshperic pressure) in all points of normal driving with a margin of safety for elevations, loads and ambient temperature variables. With racing we can throw wide range engineering out the window and target specifics. The second reason was material and clearance issues with excess retained heat in the block/heads even if the coolant is NOT boiling anywhere. Overheating effects parts (materials) in a very specific order - the first to suffer is your rings - they loose tension like any heated spring. Then the exhaust valves suffer stem wear and face/seat pitting. This is stock form using SBC as a mule - way back to gen I. NOW we have high tension chrome moly rings, one piece stainless valves and bronze guides. The op temp of my LS1 is 210 - lowering that will actually reduce the HP output. So how can the LS1 run hotter safer? better materials and cold clearnces that are wider (as the metals are hotter they obviously expand more). this is engineered into a racing engine as well (unless its a street class engine - I would not advise a street engine to run above 190). So why is retained heat a good thing? easy - as the incoming charge enters the cylinder it starts heating up from retained heat (retained heat is directly representative of op temp). That does two things. One starts expanding the charge before ignition. Remeber its not the burn that drives that piston down its the expansion of the air from the heat produced in the burn) so this increases cylinder volume filling (if you put Xcc's of air into the cyl and heat it - X value increases proportionately) and total expansion - as well as starts heating the fuel. Heated fuel ignites better than cold fuel - ask any fireman to explain flashover! You DON'T want the fuel to be heated before mixing in the carb (isolated and insulated fuel line) - and you DON'T want the charge heated until entering the cylinder (air gap style manifold and phenolic carb spacer). But once IN the cylinder you want all the heat you can get. So when you look at a high dollar engine like cup cars what do you see them doing? Increasing A in equation one and m in equation two to a point that removes so much heat the car would run 180 or even lower - then taping off the nose to reduce the value of T2-T1 in both equations and h in equation one. This makes a system that will remove virtually ALL of the heat you can make - but controls optionally how much the actual value of Q is with an external change. Then they set it so that at peak thermal product the equalized temp is around 225. Or you can not mess with tape and run a safe conservative 190 leaving very real hp gains in your coolant instead of over the pistons. I am a competitive person - I want every bit of everything that car has to offer. I do agree this is taking a few more risks - but the more risk the more the reward. The other reason I would push the temp edge in testing is really just a matter of how far can you go. To know where that edge is on the apex don't you have to push it a little (and maybe even spin once or a dozen times?) So if it's going out at 240 returning cool enough to stay there - and no coolant loss, or engine damage is occuring is that even "overheating" in any sense of the word? Nope - just a higher than stock op temp. point is - adding a restrictor reduces m. A reduction on one side of the = sign HAS to be balanced on the other. In other words Q (heat removed) went down. If I remove less heat how am I no longer overheating? Easy. Wasn't overheating to begin with - just making a lot of heat to BE removed. The restrictor did not change Eq temp - just made it less likely to boil at 11,000 ft full load 90 degree ambient! Link to comment Share on other sites More sharing options...
Danielsen Motorsports Posted July 21, 2011 Report Share Posted July 21, 2011 WooW Link to comment Share on other sites More sharing options...
Pacecar Posted July 21, 2011 Report Share Posted July 21, 2011 http://www.stewartcomponents.com/Tech_Tips.htm http://www.stewartcomponents.com/Stewart_faq.htm Link to comment Share on other sites More sharing options...
4cylfordz Posted July 21, 2011 Report Share Posted July 21, 2011 there's no chance that someone over filled that engine with rock block right? Link to comment Share on other sites More sharing options...
CC57 Posted July 21, 2011 Author Report Share Posted July 21, 2011 there's no chance that someone over filled that engine with rock block right? It's a GM "sealed" 602-crate. That would never happen, correct? Link to comment Share on other sites More sharing options...
flyingaces Posted July 23, 2011 Report Share Posted July 23, 2011 I chased and chased a overheating problem in my car, replaced every part i could, replaced heads, ripped the nose piece off (with the help of another car ) and it still overheated. come to find out my timing light went out and was giving it 13 degrees more time then what the dial was indicating. Link to comment Share on other sites More sharing options...
Blue Moon Motorsports Posted July 25, 2011 Report Share Posted July 25, 2011 Not sure why you are having all these overheating issues.....We DID have an overheating problem in races over 40 laps until we went to a triple pass radiator and a 30% underdrive waterpump pully. Didn't have ANY after that!! Link to comment Share on other sites More sharing options...
CC57 Posted July 25, 2011 Author Report Share Posted July 25, 2011 David, I wish I knew why too. It's run hot from the 1st time I took it out at Speedfest (~240 or 250), and on the warm side evey run since then. Link to comment Share on other sites More sharing options...
jwmbishop Posted July 26, 2011 Report Share Posted July 26, 2011 David, I wish I knew why too. It's run hot from the 1st time I took it out at Speedfest (~240 or 250), and on the warm side evey run since then. Have you got a read on the return (lowest) temp yet? Link to comment Share on other sites More sharing options...
CC57 Posted August 21, 2011 Author Report Share Posted August 21, 2011 Well, in case anyone is interested or can learn from my experience... Removed the shroud, sealed off the radiator cap and plumbed in an expansion tank. Results: never got over 200!!! Unfortunately, was caught up in a wreck (someone blew a motor and dumped fluid all over the track) and the 3 race old radiator is trash, and the bumper and .... The bright side is next time out I shouldn't have any overheating issues. Link to comment Share on other sites More sharing options...
HiTech Posted August 21, 2011 Report Share Posted August 21, 2011 thanks for the info ......looks like you cant get a break ...... Link to comment Share on other sites More sharing options...
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