badboy29 Posted October 13, 2010 Report Share Posted October 13, 2010 I have had 3 motors pop this year worst year ever racing I have beat myself up tring to figure the issue out. I have raced on short tracks 1/4 mile and 3/8 mile track. the motors have been built by 2 differnt motor builders.. the only common domanators are ,fuel pump, fan, and flywheel, clutch and pressure plates, drive shaft, starter, headers and exhaust X pipe. both motor builders have a great reputation and not junk these motor were not thrown toghter. With that said can anyone offer some wisdom for me to make sense...... this season has been expensive and i have wrote this year off but dont wont to put another motor in car I have become gun shy....... The first Motor lasted 6 laps RpM 7000 and oil press 70 and water temp 190 the next motor lasted about 60 laps 6800 rpms same pressure both built by same motor builder the last motor fresh out the shop breakin and 6 hot laps heat race coming to the green flag blew at the flag stand....... any wisdom on this would be greatly appreciated please no BS from the peanut gallery Link to comment Share on other sites More sharing options...
KISS_Racing Posted October 13, 2010 Report Share Posted October 13, 2010 When you say blew... In what way? So, crank, rods, cam, block and etc were all different? So, first things first. Who is tuning your motors?Is carb the same? What kind of fuel filters? Possible gas contamination? Are you running MSD box or Hi-po HEI Dist? If it were same builder I'd wonder if his gauges were off or maybe he had a new guy who was assembling who maybe rushed or missed something? Link to comment Share on other sites More sharing options...
dy97 Posted October 13, 2010 Report Share Posted October 13, 2010 did they have royal purple in em ? Link to comment Share on other sites More sharing options...
Danielsen Motorsports Posted October 14, 2010 Report Share Posted October 14, 2010 What kind of fuel, timing, compression, carb. Just cam breakin at the shop is not the complete proper break in for brand new motor. You need to use track packing, hot laps and heat race as part of the break in procedure as well. How did you break in the camshaft and motor what procedure did you follow? Lastly what exactly broke? Link to comment Share on other sites More sharing options...
badboy29 Posted October 14, 2010 Author Report Share Posted October 14, 2010 I had the same carb, and distributor on the first 2 motors on the last one diffrent carb and distributor... carb were quadrajets, and distributors were HEI. in all three the timing was set at 34 degrees and the breakins were shop break in and hot laps in 2 ocassions I started the heat races and never finished. I have checked and rechecked the fuel train there is no resrictions or blockage I had a inline fuel filter from the pump to the carb. After the first motor to be on the safe side I installed a fuel log on the frame rail with filter to insure that I wasnt having fuel issues. In all 3 motors i was running racing gas 110 octane the oil has been difffrent as well all have been 20w 50. I dont know about the last 2 motor yet but the first motor I dropped a valve. in all 3 motors running flat top 4 valve releif pistons HYP and HObby stock legal motors. The last motor that I had a issue with was all completely diffrent components 30 over motor the first 2 were 60 over motors. ther were no short cuts done on any of the motors. The 2 motor builders have motors running in all classes such as Limited, Hobby Stock, and Pure Stock as well as Street Stock running up front and no issues. Link to comment Share on other sites More sharing options...
Truck99 Posted October 14, 2010 Report Share Posted October 14, 2010 Sometimes things just happen. I know we always want to find the root cause so we don't repeat any mistakes, but sometimes that will never happen. One question about your motor(s) - what type of harmonic balancer are you using and was it the same one on all 3 motors? What broke on the motors? Different parts or a common type of failure? Link to comment Share on other sites More sharing options...
KISS_Racing Posted October 14, 2010 Report Share Posted October 14, 2010 There is a fuel company who has been known to have been having drum issues. Since I don't want to bash that company I wont be posting it's name. I know of a shop in San Antonio that lost 3 - 4 motors and they all had run fuel from two seperate drums. Ultimately the shop owner traced it back to the fuel and the drums. Filter your fuel through a funnel that has a filtering system. Was it an intake or exhaust valve? Link to comment Share on other sites More sharing options...
jwmbishop Posted October 14, 2010 Report Share Posted October 14, 2010 Failure analysis is where I made my mark on the industry and is what directly led to a job offer with a team that could have moved me up into cup engines (which I turned down due to starting a family). It is impossible to do once the engine is all torn down - it must start with removal continue thru disassembly, and cleaning - sometimes even in remachining an invloved part and requires careful comparison to build, assembly and operation notes. Over the net me and everyone else are just tossing out WAGs. best bet would be to let the machinist who built it play with the pieces and see if he can backtrack to what started the failure, as most failures start small and get big fast. dropped valve could be exhaust temp issue which is prolonged lean, oil in chamber (which is always present until fully broke in) wrong heat range spark plug for comp and cam, even the hood of the car creating a vacc at the carb inlet - (acts like lowering the atmospheric pressure !), it could be an oil return problem, rocker geometry, fuel SpecGrav issue, it could be a myriad of things with so many clues there is no way to list em all - most of them you will spot as you go thru it all. Something that looks irrelevant only becomes crucial when it becomes part of the backtracking! Unless you are using very standardized and checklisted procedures the common denominator will rarely be common - you possibly could have made a different mistake each time. Which is precisely why oftene - whether right or wrong - it will just be chalked up to a loose nut on the torque wrench. Link to comment Share on other sites More sharing options...
1955chevy33 Posted October 15, 2010 Report Share Posted October 15, 2010 Its hard to tell whats happening and to give advice if you havent checked the motors to see what happened to them. A valve going on the first motor at 7000 RPM doesnt sound too bad. The second two motors you said you dont know yet what happened to them. All 3 motors could have completely different issues not caused by the same thing. Best idea is to find out what happened to all 3 then look for a solution. JMO and I hope your luck improves. My luck has run about the same as yours this year ! Link to comment Share on other sites More sharing options...
badboy29 Posted October 15, 2010 Author Report Share Posted October 15, 2010 Thanks Guys i will do so It has got expensive to race this year and the consenses local has been the same........... the price tag for this year has been over 10000 or better on motors befroe i invest another dime I will investagate all possibilitys Link to comment Share on other sites More sharing options...
walt Posted December 27, 2010 Report Share Posted December 27, 2010 Compare your timming light with someone elese's Me and a buddy of mine( using the same light) lost our motors due to a snap on light that at what we thought was 34 degrees turned out to be 48 degrees on a hot summer night those motors didn't like that timing . as the saying go's it ran great just before it blew LOL Link to comment Share on other sites More sharing options...
4cylfordz Posted January 6, 2011 Report Share Posted January 6, 2011 sounds like the exhaust valves are hanging up, EQ heads? or oem with new bronze guides. Ive seen quite a few of them stick and usually happens within the first few nights. i figure it has something to do with the poorer quality of material used in guides these days causing them to swell.... double check the valve to guide clearance maybe run a .346 reamer threw them and consider leaving the exhaust seals off next time. Link to comment Share on other sites More sharing options...
poorboy Posted January 7, 2011 Report Share Posted January 7, 2011 Piston to valve clearance is my guess. Did the engine builders build the complete engines or just the shortblocks? Link to comment Share on other sites More sharing options...
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