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CBraden

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CBraden last won the day on September 5 2013

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  1. CBraden

    What fuel pump?

    I have heard good things about the Carter above, as another option, I have had good luck with this one: https://www.amazon.com/gp/product/B000DN7VLK/ref=oh_aui_search_detailpage?ie=UTF8&psc=1 I run it dry all the time and it doesn't seem to mind (can't say the same for the downline Walbro that failed in ~100 hours of use, with only a few supply hiccups when the surge was going dry). YMMV
  2. Based on my small sample size of experience, high rpm (within factory redline) without added power doesn't mean impending doom for an OE engine. Valve springs and lifters have been items which have failed for us in different motors, but now we replace those and don't know what will fail next. Bottom ends have not flown to pieces for us, but we try to run stuff widely regarded as reliable. I am not picking on any makes, but there are some engines that seem less happy with the use case. Interesting links on the topic: bbobynski Joined: Apr 2005 Posts: 79 Detroit, Michigan It is a bit off topic but I will share this anecdote if you are worried about breakin on a new production engine. We did a program back in the mid 90's to determine what sort of engine "hot" tests worked best and to investigate a number of other things. The "test" was done thru Jack Roush's engineering group and contracted on their dynos. It involved taking 150 brand new, 300 HP Northstar engines that had never been fired and running a 2.5 hour hot torture test on them with a post test teardown. The engines were stone green at the start of the test. They were each installed on the dyno and the coolant and lube systems hooked up. Coolant was preheated to 255 F by the test cell equipment and oil was preheated to 285 F. This was done with 50/50 DexCool/water and conventional motor oil...not synthetic. The engine was fired and IMMEDIATELY put at full throttle where it ran at 6000 + RPM at full load with the oil temp controlled at 285 to 300 F. It was harder to get the dyno equipment to live than anything else....LOL. There were no engine failures at all. None. All engines were torn down and judged to be in "like new" condition on all parts. No scuffed pistons, no damaged bearings, nothing. In fact, it was difficult to tell that most of the bearings had even been used as they absolutely looked brand new even under magnification. To say that it was eye-opening to a lot of people was an understatement. The Roush dyno techs thought that we were nuts and would stop after the first few engines blew up....LOL. The only caveat here, is that each engine had the oil routed thru the oil heater and oil cooler equipment which necessitated separate filtration so that any debris generated during the first few minutes of operation that might have bypassed the filter otherwise running at 6000 was caught by the external filtration (it was needed to protect the cooler/heater heat exchangers if there was a problem) so the test indicates performance of fits and finishes of a brand new engine and oil capability at those temps and such but doesn't perfectly replecate a car run immediately to full throttle, 6000 RPM and held there for 2.5 hours..as if you could do that somewhere....LOL. I was the development engineer in charge of this test so I saw it happen, saw the engines at teardown and compiled the results. Anyone concerned about stabbing the throttle during break in can rest easy. Trust me. (above from this thread: https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/129895/2 ) https://www.hemmings.com/magazine/hsx/2009/10/Run-for-the-record---Saab-9000-and-900/2130431.html https://www.motorauthority.com/news/1118232_all-srt-products-undergo-24-hours-of-racetrack-endurance-testing https://www.bobistheoilguy.com/forums/ubbthreads.php/topics/1779600/1 We live in a really nice time to be racing used cars...
  3. Counterpoint: Adding safety in many cases includes adding weight. Not penalizing the decision to choose safety over weight is something to consider. Especially because some will forego additional easy safety features (leaving OE crush structure, etc) in order to maximize weight savings.
  4. CBraden

    V6 F-body point increase in 2001

    How heavy are the Gen II vs the Gen III / Gen IV if you happen to know. Also, I would love to race a Gen II but they are incredibly overpriced around my neck of the woods. A shell with a moldy interior seems to fetch $2500 if the asking prices are any indication. Meanwhile I can buy a running driving e46 330i for less than that.
  5. CBraden

    Time to revisit 2X shocks?

    This makes sense to me. But like everything rules-ish in this series, there will be slippery slope arguments will start very soon.
  6. CBraden

    Official 2018 Harris Hill - Fall

    Such a dangerous claim to make about a racecar, especially before a race. Good luck UA!
  7. CBraden

    Connecting Rod Decision

    Thanks, will not be re-using pistons (block needs cylinders bored/honed). Got it! I will not respond to any more rules type questions here for that reason.
  8. CBraden

    Connecting Rod Decision

    Ideally not more than equivalent power to weight cars. But that is for a different thread...
  9. CBraden

    Connecting Rod Decision

    No because weighing racecars is a mystical dark art that was deemed not feasible for this race series. The calculator assumes that your car weighs less than stock by some % (even though clearly this is a bad assumption for some swapped cars, more so if they choose to swap to a beefier rear end and run wheels and tires 3x the 155x13 OE wheel+tire weight). Since there is already a million page thread on this, let's please not open this quagmire again on this thread - PM me if you care to get into details, it is what it is.
  10. CBraden

    Connecting Rod Decision

    No, it is really just a front running car in this series. The formula in the swap calculator for an Opel GT with over 200 hp is ludicrous, try it for a laugh. I tried to argue that real weight (in this case >2500 lbs) is all that matters, but my arguments did not prevail... the car was designed under the old rules, if I built starting today I would pick a different car that would be faster and have more fuel, and be a 500 point car.
  11. CBraden

    Connecting Rod Decision

    I understand the limitations of powdered metal and hyper-eutectic pistons, and feel good about the safety margins designed into these OE parts in this application/power/rpm level. I think I am hearing a consistent theme of less weight is the more important factor, and that pressed pins are absolutely fine. Thanks
  12. CBraden

    Connecting Rod Decision

    V8, hypereu piston - pin+piston weight is same for OEM pistons (pressed and floating), but I will likely buy replacements and getting pin weights for them before buying isn't easy on all options under consideration (which seems wrong). Crank will get a spin balance after parts are selected (and I will check part to part variance and grind as necessary before that) Thanks.
  13. CBraden

    Connecting Rod Decision

    Sorry I should have clarified, the car is 100% EC (literally over 15,000 points, I am not kidding) so the valuation rules are not part of the decision, only finding the best technical option. Thanks for reply
  14. CBraden

    Connecting Rod Decision

    Both of these are OEM rods, just different year models. The question in my mind is it worth 41 grams to have full floating pins. I don't care what anyone thinks once the engine is built, I want to make the choice that gives the engine more longevity at high rpm use. I have not experienced a failure mode, just building new engine to use an aluminum block and trying to pick the best of the OEM options to go in the new build. I'll count this as a vote for pressed + lighter, thanks. Both powdered metal cracked rods, and both OEM from different years. Thanks
  15. Given the choice to pick between to equal length connecting rods, both of sufficient strength for your application, which of these do you choose: 1) Pressed pin I beam 616 grams 2) Floating pin I beam 657 grams Assume pistons weigh the same. Application is a road course endurance racing engine which will live under 6500 rpm. Piston speed under 5750 fpm. Stroke ~3.27" if it matters. If you care to share... What would you do and why?
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