hi grumpy
i had my first dyno run with my camaro today. it was a brand new 4wheel drive dyno. so they strapped it onto and the guy did the 2 pulls. the engine is a full aluminum merlin-x 540cui, 10.7CR, brodix bb2-x heads with 320cc runners, comp-cams 11-771-8 solid roller cam. desktop dyno and comps cams software both came up with around 680-700 hp/ft-lbs on the engine. i knew that software and real life differs but my dyno run came up with 458HP flywheel and 436HP at the wheels. torque was @500ft-lbs. it has a tremec 5speed with a dual disc clutch. the torque curve jumps up at 1900rpm and is nice and flat but the hp curve falls off from 5400rpm. any thoughts on it? is that just what it is or is something way off? my buddy did a run with his 500cui stroker roadrunner and he was even 100hp/Nm lower than i have been.
thanks,
can you post a picture of the dyno sheet?
you should be making better numbers than 436hp so obviously somethings wrong
i emailed you the sheet as a pdf file
OK, first let me apologize for not getting back to you faster I had a family minor emergency last evening,
(my sons dog got rushed to the VET where he died, we had that dog for 12 years and it kind of side tracked everyone last nite,)
OK,back to diagnosing the issue at hand,I hope you have a second matched engine data sheet, because most dyno results produce more detailed info, like the data sheets Ill provide, here, posted below,as examples, a great deal more info like these posted below helps isolate any problems as would a list of All engine components used, ALL FLUID and AIR TEMPERATURES, BSFC FUEL/AIR RATIO,IGNITION TIMING, ADVANCE CURVE, ETC. If we have that info we can make more educated guess work as to the problem.
ONE THING WAS RATHER OBVIOUS ,LOOKING AT THE POSTED DYNO,
your peak torque is at about 3900 rpm, and on a 540 that seems to indicate, some restriction to flow, your cam might be a bit less than ideal duration for the application,or your intake or exhaust is restricted, both can, be further proven or found to be ok with plenum and exhaust pressure/vacuum readings and knowing your BSFC and ignition timing,port flow , exhaust back pressure etc. thats why having the data sheet helps
your heads intake port size is certainly large enough, but either the intake design or the exhaust back pressure or cam timing could be restricting flow, a properly set up 540 BBC designed for producing max power,should easily produce power to at least 6000-6200rpm
i had my first dyno run with my camaro today. it was a brand new 4wheel drive dyno. so they strapped it onto and the guy did the 2 pulls. the engine is a full aluminum merlin-x 540cui, 10.7CR, brodix bb2-x heads with 320cc runners, comp-cams 11-771-8 solid roller cam. desktop dyno and comps cams software both came up with around 680-700 hp/ft-lbs on the engine. i knew that software and real life differs but my dyno run came up with 458HP flywheel and 436HP at the wheels. torque was @500ft-lbs. it has a tremec 5speed with a dual disc clutch. the torque curve jumps up at 1900rpm and is nice and flat but the hp curve falls off from 5400rpm. any thoughts on it? is that just what it is or is something way off? my buddy did a run with his 500cui stroker roadrunner and he was even 100hp/Nm lower than i have been.
thanks,
can you post a picture of the dyno sheet?
you should be making better numbers than 436hp so obviously somethings wrong
i emailed you the sheet as a pdf file
OK, first let me apologize for not getting back to you faster I had a family minor emergency last evening,
(my sons dog got rushed to the VET where he died, we had that dog for 12 years and it kind of side tracked everyone last nite,)
OK,back to diagnosing the issue at hand,I hope you have a second matched engine data sheet, because most dyno results produce more detailed info, like the data sheets Ill provide, here, posted below,as examples, a great deal more info like these posted below helps isolate any problems as would a list of All engine components used, ALL FLUID and AIR TEMPERATURES, BSFC FUEL/AIR RATIO,IGNITION TIMING, ADVANCE CURVE, ETC. If we have that info we can make more educated guess work as to the problem.
ONE THING WAS RATHER OBVIOUS ,LOOKING AT THE POSTED DYNO,
your peak torque is at about 3900 rpm, and on a 540 that seems to indicate, some restriction to flow, your cam might be a bit less than ideal duration for the application,or your intake or exhaust is restricted, both can, be further proven or found to be ok with plenum and exhaust pressure/vacuum readings and knowing your BSFC and ignition timing,port flow , exhaust back pressure etc. thats why having the data sheet helps
your heads intake port size is certainly large enough, but either the intake design or the exhaust back pressure or cam timing could be restricting flow, a properly set up 540 BBC designed for producing max power,should easily produce power to at least 6000-6200rpm
