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bhusselbaugh

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About bhusselbaugh

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    NASA racing
  1. Also, you may have done all of that without issue, but did you run the car at Daytona, on a 90 degree day, with a VMP boost pulley and tune (with boost at 12 PSI)? Because I ran the car at Roebling with no issue. I ran the car at Sebring with no issue. It was Daytona - with 30+ seconds of flat out on those banked curves - way more than any 1/4 mile pass - before jogging back through the infield part of the course and then back out on the banked curves - that did the engine in.
  2. I'd be interested to see how the engineers at Ford feel about that comment. BTW - I have been working on engines for over 40 years - started well before I became an engineer. It is possible to have experience and a degree. What I am new to is racing - so the demands put on the engine due to that environment are new to me - that I will admit.
  3. Say what you want - buy what you want. The transmission oil also boiled - that had nothing to do with the viscosity of the engine oil.
  4. Yet another update. I purchased and installed a larger heat exchanger with integral fans as well as a 3X larger coolant tank for the intercooler. I ran and data logged the car today and noticed only 7 degrees F decrease in maximum IAT2 - on a day when ambient temperature was about that much lower than the baseline logging I did. I then re-ran the heat calculations (basically, heat added due to compression of any kind can be calculated by T2 = T1 x (P2/P1)^.28. Just make sure temperature is expressed in absolute (use the Rankine scale if you're working in F). I had made an initial mistake in my calculations on anticipated after compression charge temperatures that led me to believe you could see huge gains even with small differences in IAT2. When I corrected my calcuations, assuming a 9:1 compression ratio engine (which mine is), a 10 degree F decrease in IAT2 represents only a 18 degree F decrease in post combustion chamber charge temperature. Not enough to have much influence over detonation - which is what I experienced today during data logging. (I originally mistakenly calculated a 128 degree F reduction in combustion chamber post-compression charge temperature). I know there are many who swear by swapping out the intercooler's heat exchanger - which is what I did - and I can tell you through data logging that it made a difference - but not much of one. Now that's the measurement of max to max for the same run. The larger capacity heat exchanger may pull heat faster and allow IAT2 to recover faster when you get off boost - probably does. The biggest difference so far seems to be due to the radiant heat shielding - oil temps are down 30 degrees F.
  5. Follow-up. In addition to fine tuning the "tune", I have worked on the primary issue of heat. I have added radiant heat shielding at the rear of the engine to stop radiant transfer from the exhaust to the bell housing (which then gets conducted forward toward the engine and backward toward the transmission), as well as a shield between the exhaust and the very exposed driver's side of the block and oil pan. Interesting thing - you think an aluminum oil pan will help cool the oil, but it also can help heat the oil, which is what is happening. Aluminum is a great conductor of heat and with all the heat being radiated at the back of the engine it ends up picking up that heat and heating the oil. When I had the engine rebuilt, I had Livernois raise the CR to 9.0 and increase the bore - so the engine now displaces 5.88 L. At Livernois' suggestion, I added a 2013 8 quart aluminum oil pan as well as an MMR external oil cooler. I had the Ford dealership install the oil cooler while they built the engine to the long block and reassembled it in the car. I recently purchased a larger intercooler radiator with integrated fans and added that. While I was adding that, I looked at how the dealership had mounted the external oil cooler (they strapped it directly to the air conditioning condensor). The weight of the oil cooler was already starting to bend the cooling channels on the AC condensor - so I pulled ot off the condensor and built an aluminum frame for it. This allowed me to space it away from the condensor. In all a very tight fit up front with 4 different heat exchangers now. Another change I made was a 3x capacity coolant tank for the intercooler. I like the stock look of it. Long ago I had cut out the area in front of the built-in nipples for brake coolers and installed functioning brake coolers. That was my first heat issue - boiling brake fluid.
  6. Not sure why you think I'm throwing the tuner under the bus. (unless maybe you're a tuner) The background story is probably masking what I'm really saying - I paid for a tune that, when I went behind the tuner and looked at what he did, was, in my opinion, hastily slapped together and was not an optimal tune for my car. What's more, he left timing - the starting timing - too far retarded and retarding the timing raises exhaust gas temperatures. He also turned off 16 PCM switches to stop the PCM from reporting various check engine codes - that's downright dishonest in my opinion. In the old days, you could go into a shop complaining of noise in the rear end, and the mechanic could "fix" that problem by putting a banana in the rear. The noise would go away, you'd pay your money and think your problem was fixed. Now, is that honest? Turning of the PCM's ability to thrown check engine codes in response to someone complaining of a certain code is the same thing - just today's way of doing the same thing. That's what I'm pointing out - that these "tune by mail" tuners are all likely doing things just like that - because I can't see how you can tune a car without actually spending quite a bit of time with it. That's the main point of my post - I guess I added too much additional information and that point got lost. As far as why my car engine blew up - I said early on that I believe it was a combination of several factors - and the tune may have been one of those factors. Heat dissipation is another factor I pointed out - and I agree it's the largest - but I know that now (and didn't then).
  7. Good info - thanks. I do now have an oil temp gauge on the A pillar. I also backed the boost down a bit. Plugs have been gapped (but not a colder range - yet). I did put radiant heat shielding (with air gap in places) to protect the engine and bellhousing.
  8. Good points - like I said I only point a partial finger - and that's largely due to the one tune I paid for that I felt was quickly knocked out and caused the car to run poorly- and it was done by VMP (I didn't name them originally, but that is who did it). I agree that better intercooler heat exchange will assist in lower EGTs - maybe even to the point of nullifying the need to address the radiant heat transfer from the exhaust. I have done actual engineering calculations - and I know many who don't have engineering backgrounds tend to dismiss that - but I contend that you can't fully trace a problem to its root if you don't understand the physics and identify and address all of the contributing factors. You may get lucky and/or address a symptom, but the underlying root is still present - so I do attempt to trace all problems to their root. I have ordered a better heat exchanger for the intercooler but I have also added radiant heat shielding under the car protecting the engine and the bellhousing. Ford had two small radiant heat shields - basically protecting the floor so that your feet don't burn I guess. There is no radiant shielding to protect the engine and tranny. And your point about not knowing what I was doing running that car at higher boost levels on the track - that's a valid point. It's only the pain of having blown up that engine and paying to replace it that now has me kicking into engineering and analysis mode to make damn sure it never happens again. Maybe I should have done this analysis earlier - but the motivation wasn't there as I naively thought I had bought a track-capable car from Ford.
  9. The other thing that others should be aware of is that Ford pointed the full finger in that direction. They refused to cover the damage since I had modified the car. Ford was basically suggesting that I go after VMP.
  10. Yes, I'm pointing a partial finger in that direction - as I said I think the root cause of the failure is absorbed radiant heat with no good path for dissipation - and that extended high RPM running - even without detonation - would result in very high oil temps due to that. I was also pointing out that, based on the tune I received, there was significant timing already pulled out in the base tables - so the starting point would yield higher EGTs before the PCM even started any protection strategies. And I was also pointing out wholesale turning off of PCM switches to stop it from throwing various codes - which customers should be aware may be common practice. I suspect you may work for or have some interest in VMP.
  11. Track conditions at Daytona that weekend = sunny, temps in the mid 80s, moderate humidity. Yes, live and learn on the "trusting others" front. I trusted the stuff I got from VMP based on nothing more really than seeing the advertising everywhere and I trusted the dealer to put the OEM oil in it and I trusted that Ford's recommended oil was the best for the car. I even trusted that Ford actually designed that car for track duty (I bought into their marketing). I can tell you now though, having learned the hard way - to the tune of $20K - I run Driven (Joe Gibbs) Racing oil 5W-50. I do my own oil changes. And I now control the tune. As far as did I notice anything - yes my first indication was that the car suddenly seemed slower on the banked curves - but the thought of oil starvation didn't enter my mind. One lap later I heard the rod knock and as soon as I heard that, I limped back off the track and had the car flat-bedded back. As far as the car not being designed to handle what I was doing - the racing school I attended (Miller motorsports) was running stock 4.3L 3V Mustang GTs. We ran those cars hard and they were bullet-proof. I think in my case it was a combination of many contributing factors that, if any one of the factors had not occurred - the outcome would have been different.
  12. They may have, but it is also likely the lesser quality oil experienced sheering due to extreme heat. The lighter components then boiled off. The dealer did say what was left in the car was more like a sludge than oil - which would indicate the lighter components boiled off.
  13. Interesting - so I followed up on this topic and did the thermal calcs for a 9:1 CR (I had the new engine's CR raised to 9:1). At 9:1 assuming 90 F ambient temp, if I can get a 10 F decrease in after-intercooler air temperature that will yield a 148 F reduction in cylinder temps after compression. So there is a strong case to be made for increasing the efficiency of the intercooler's heat exchanger. Having said that and analyzing radiant heat transfer (and observing oil temps as measured in the oil pan exceeding 100 F over coolant temperature - meaning that the top end of the block and heads are running at 100 F (with some obvious variances) cooler than the oil at the bottom of the engine. The only thing that explains that to me is that the oil is being heated from a source external to the engine - and the most likely source is radiant heat from the exhaust. Even if that exhaust is running well under temperatures that might damage the cats, it is still emitting radiant heat energy and that heat is being absorbed and transmitted by the aluminum bell housing, transmission case, and engine block. And, given limited airflow across the back of the engine, the heat has limited means for dissipation, so it builds and the result is increasing oil temps. The root cause solution for the high oil temps is radiant heat shielding near those exhaust downpipes and cats. I hesitate to simply wrap those components as I want them to be able to exchange heat with the air - I just need to block radiant heat transfer to the bell housing and block. However, that significant decrease in cylinder temps that can be had by even a 10 F decrease in IAT suggests that increasing the intercooler efficiency will be well worth the investment. It will allow more timing which allow increased power (and reduced EGTs)
  14. Correct. Although I would argue beefing the intercooler would not have completely solved the problem. EGTs were more affected, in my opinion, by late timing. I have done the thermal calculations on IAT and have concluded the Shelby's intercooler is 72% efficient. Raising that efficiency might result in 20 degrees lower IATs, which would allow bringing in some more timing - so it may assist in lower EGTs - but I suspect based on the tune I have gone through that timing was too conservative in the first place. The real fix, in my opinion, is to introduce radiant heat shielding in the area of the downpipes - to protect the transmission (bell housing is closest point to exhaust) and rear of the block - which I'm in the process of doing. I'll know during the next track session if that makes a difference.
  15. BEWARE WHEN YOU ORDER THAT CUSTOM TUNE – DYNO OR OTHERWISE! This is an important message to read as it exposes what is likely common practice in the tuning industry – and the consequences could be expensive. Before I begin, a little background: I have a 2012 GT500 that I have modified. Originally the modification was a smaller drive pulley on the supercharger and tune by VMP Performance. The original tune was locked by Justin Starkey of VMP and, although I have SCT’s Advantage software, I was unable to modify the tune (and didn’t need to as the tune seemed to work fine). In November of 2015 I was running the Shelby at Daytona in NASA’s HPDE 3 group. On the first session of the second day, the engine developed a rod knock and I had the car flat-bed towed back to St Petersburg, to the Ford dealer where I bought the car. The dealer did what they could, but in the end, Ford refused to cover the damage, even though the car was still under warranty. Before you immediately dismiss considering that they would even think of covering it since I was running it on the track, they actually initially agreed to cover the damage and then refused based on the fact that I had modified the car. They cited extreme detonation (which was not the case, but was more their way of CYA). What did happen is that the engine oil boiled – vaporized and exited the engine through the PCV system. Only 2 quarts remained in the engine when the dealer tore the engine down. There are many theories as to why the oil boiled (Ford’s theory was that the detonation caused the rings to be forced hard back into the ring lands, allowing the oil to pass and be burned). My theory is that it was a combination of events: The dealership possibly put the wrong oil in the car when I had it changed (they were always pushing the cheaper Penzoil) Ford did a very poor job designing heat extraction from that car, and the back of the engine was exposed to extreme radiant heating in the area proximate to the exhaust down-pipes. The aluminum block afforded great heat transfer resulting in high oil temperatures. Keep in mind the ECT was normal during this entire event. Also, the car was covered in the rear with transmission oil – the transmission had gotten hot enough to also boil its oil, which escaped through the transmission vent hole. The tune was too conservative on timing, resulting in higher EGTs, thereby contributing to the radiant heating Now, fast-forward. After spending $20K to have Livernois repair the block and rebuild it to a short block (Livernois does outstanding work), to have the dealer rebuild it to the long block and re-install it, along with adding a larger oil pan and external oil cooling, I paid a well-known tuner for a custom tune (and this time paid extra to get the SCT source file so I can view how the car was tuned and make adjustments). I also paid the tuner to do a dyno tune so I didn’t have to spend the time tuning-testing-tweaking-tuning the car. The dyno tune lasted about 2 hours and consisted of 3 “pulls” on the dyno. The tune started with a tune from another car as the initial baseline, and some adjustments were made as a result of the 3 pulls. That weekend, I ran the car at Sebring, again in HPDE. The car ran 300+ degree oil temperatures. On one session it threw an engine code (Misfire, cylinder 1). I had complained to the tuner that my AFR gauge was showing a rich condition under WOT, but that was explained away as a faulty AFR gauge and wasn’t addressed properly (in my opinion). The main thing was a significant reduction in power from how the car previously performed – naturally aspirated Mustangs were able to catch me in the straights and the car was at least 15 MPH slower in the back straight than the previous time I had run at Sebring. I lost confidence in the tuner and decided to spend the time tuning the car myself. It took weeks – with up to 12 different tunes tested along with driving/logging – before I finally got the car tuned properly (meaning power has been restored, oil temps are down 20 degrees, detonation is gone, and the fuel curve is correct). I then did a compare, using SCT’s software, between my final tune and the tuner’s “dyno” tune. Below are the salient points: Borderline knock tables (used as a starting point for ignition timing) In the area of low RPM – high engine load the tuner had the timing set to 1 degree advance. This resulted in detonation. My final tune has up to 9 degrees retard at the highest load/lowest-RPM point. In the area of low engine load the tuner was very conservative on timing, resulting in sacrificed power (and increased exhaust temperatures). Up to 10 degrees of timing was added resulting in much better low end torque (with no detonation) Even in the mid-range of RPM/load the tuner left up to 6 degrees of timing off the table, again resulting in increased exhaust temperatures and sacrificing of power. The tuner had set the Y-normalizer table to essentially lock the entire range of operation to just a few rows of the table. This seemed to me to be a quick fix – instead of tuning for various RPM-load points. MBT timing table (used as the reference for the best engine timing as determined by the MFR) Much of the table had been scaled back (timing removed) from stock. This made no sense to me as the MBT table is the reference for the maximum timing to demand (theoretically, since MBT represents the best timing in an otherwise perfect world, there should be no reason to change these tables from stock). The MFR most likely spent hundreds hours of test in determining these values. I put the table back to stock values. The tuner disabled clutch protection. This may be desirable for launching hard in drag races, but I had told him I road race the car so launching hard is not an issue. I re-enabled it and put the settings back to stock. I suspect the settings were from a previous tune that was used as the basis for this tune, and were overlooked. The tuner turned off 16 different code switches, essentially disabling the PCM from reporting those diagnostic codes. Such codes as P0175 and 74 (reporting rich conditions). This is, in my mind, one of the most egregious and unprofessional (by engineering standards) things done. I can think of no reason to do this other than to prevent the tune recipient from subsequently calling up and asking for the tune to be fixed because the car is now throwing a check-engine code. This eliminates that from happening but leaves the unsuspecting customer open for possible engine-damaging scenarios that now go unreported. Knock sensor When I was with the tuner during dyno tuning, he said he didn’t trust the knock sensors on my car and, although he did not disable them, he severely limited their operation by entering the maximum retard as 1 degree. I experienced detonation almost immediately upon running the car and changed the max retard to 10 degrees (stock is 6). I also confirmed, through running the car on the street while data logging (1 driver, 1 logger) that the knock sensors work well – that they do indeed show knock when there is audible detonation. Spark retard for ACT and ECT The tuner was conservative in these tables as well – pulling out up to 10 degrees for ACT values of 160 degrees. I did a calculation of expected ACT using Corky Bell’s book called Supercharged (I highly recommend it) and pulled out less timing. While this is a bit of a nit, I point this out as the final timing number is a function of borderline knock, MBT, ACT, and ECT tables (as well as anything the knock sensors might be doing) Anyway, what I feel was done is whatever was necessary to get me off that dyno quickly. The tuner assumed I did not know anything. I did not witness any dialing in of the MAF transfer function – especially in the high load range (at the tuner’s suggestion, I put an ATI 10% overdrive pulley on the engine which brought the boost up to 15 lbs, and I suspect the MAF transfer function was not correct in that range of boost and resulted in higher reading of air ingested than was really entering the engine, resulting in over-fueling.) I also did not witness tuning at various load points – just three full throttle pulls (with data logging). As an engineer, I can’t see how you can properly tune a car without studying it’s performance at various RPM/load points. This may be isolated or it may be standard operating procedure in the tuning industry. Beware if it’s the latter! As I mentioned, this tuner is well known and you will find his advertising in all major car magazines. About me – I have a BS and MS in electrical engineering and I have designed hardware and software for control systems (like a PCM) – so I find the PCM’s operation and the control tables to be intuitive. I have also worked on cars for over 40 years. I am also a member of Mensa. What I don’t have – and what I thought I was paying for – is the “tribal knowledge” that comes from doing this for a living. What I got instead, in my mind, is a quickly thrown together tune that did not result from proper engineering discipline – one that caused the car to run poorly and possibly contribute to the high oil temperatures that caused the original failure. If anyone is interested, I will be happy to share the SCT comparison file between the two tunes. Oh, and by the way, while I’m on the subject of superchargers (again I highly recommend Corky Bell’s book), I see much on the forums about Eaton’s TVS-style roots blowers – comparing them to other blowers and claiming superiority due to flow rate. The real thing that should be compared is thermal efficiency – how much heat will it produce meaning how much intercooling will be required and/or how much timing will have to be pulled out to stop detonation. Roots style blowers – or any blower that does not have an internal compression ratio (meaning they just move air from one side to the other) – have the worst thermal efficiencies. That’s because the compression of the air happens on the output side of the supercharger – so that’s where the heat is added – with limited chance to dissipate prior to the intercooler. Twin screws are superior for thermal efficiency because the compression happens between the screws, allowing the body of the supercharger to help in dissipating the heat before it reaches the intercooler. More expensive but they will allow higher levels of boost without detonation. PV=nRT – pressure goes up and volume and air mass stay the same means the temperature has to go up. Could be TVS has better thermal efficiency than previous roots designs, but it is still a roots-style blower (meaning no internal compression ratio).
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