evilwrench Posted February 4, 2015 Report Share Posted February 4, 2015 I'm shopping for a Volvo 780 and I want to have it inspected and a dyno pull done by a shop other than the seller. A salesman told me that it should make 78% of rated power or more. Does that seem low? I think I'd be a lot happier with 85 or 90%. What has been your experience? Link to comment Share on other sites More sharing options...
Nigel Posted February 4, 2015 Report Share Posted February 4, 2015 According to Jack's site dyno should be 80 percent or better if I read it correctly. I think you always have some loss between the crank and the rear wheels. http://www.jackdanmayer.com/Selecting%20Your%20HDT.htm#Evaluating%20a%20Potential%20Purchase Nigel 2006 Volvo VNL 430, 2006 smart cabrio cdi, 2000 Triple E Topaz 30' Link to comment Share on other sites More sharing options...
dzlnut Posted February 4, 2015 Report Share Posted February 4, 2015 the hp/tq loss also depends on what elevation your at Link to comment Share on other sites More sharing options...
SunJuniper Posted February 4, 2015 Report Share Posted February 4, 2015 elevation does effect the HP/TQ. do a dyno at 5k feet (like denver) will be different than at sea level.. the blowby from the dyno are VERY important too. Fulltimer Class of 2007 1998 Volvo VNL64T610 Detroit Series 60 12.7 470HP/1650TQ Eaton 18spd 228"WB Tandem2006 40' ToyHauler 3 slides and a 14' Toybox Link to comment Share on other sites More sharing options...
shorts Posted February 4, 2015 Report Share Posted February 4, 2015 dyno numbers can be misleading unless they are corrected to SAE standards for elevation, tempature, humidity and barometer readings, then figure approximatly 10 or 15% for driveline loss. If you get a good 80% corrected number and the blowby is low relative to the factory tolerance/allowance it's probably a good sound engine, just remember it's not new and anything can happen at any time. Link to comment Share on other sites More sharing options...
evilwrench Posted February 4, 2015 Author Report Share Posted February 4, 2015 All good points, thanks for the help. I got stung buying a boat without a survey a few years ago so I'm trying to be a little smarter about this . Link to comment Share on other sites More sharing options...
chevy3500 Posted February 4, 2015 Report Share Posted February 4, 2015 Don't mean to hijack this thread, but whats an average cost to have a truck dyno done? Thanks Link to comment Share on other sites More sharing options...
spindrift Posted February 4, 2015 Report Share Posted February 4, 2015 If a tandem axle, we use a 25% loss factor. If a single, we use 20%. A basic dyno run will cost $375.00 2012 F350 KR CC DRW w/ some stuff 2019 Arctic Fox 32-5MCindy and Tom, Kasey and Maggie (our Newfie and Berner) Oh...I forgot the five kids. Link to comment Share on other sites More sharing options...
Recommended Posts
Archived
This topic is now archived and is closed to further replies.