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Steve Tinker · 08-17-2009, 05:23 PM

I love these discussions.....
I'll go along with Pedro on dyno's & their operators.
My experiences with dyno runs (mostly with motorcycles I must admit) is they are basically to give you just that - a baseline. Thats why SEVERAL runs must be made on the same day, preferably @ the same atmospheric temperature and humidity and (of course) on the same dyno.
On road engines (but not race engines) the first run nearly always shows the lowest HP and torque figures because a) the fluids are not always up to a highe enough temp (especially the transmission oils) and b) the engines have usually a lot of carbon and oil buildup in the rings and valves from normal day to day running.
Owners look shocked when they see chunks of carbon and soot emitting from the exhaust as their engines are opened up for the first time, quickly followed by the pall of oil smoke on the overrun after the first dyno run....
But its the 3rd or 4th hard run that gives you the baseline from which to compare engine outputs that really mean anything - that's when the engine is fully warmed up and the combustion chambers are cleaned out.
Pedro may well be fine tuning the basic Porsche design and for the cost, it won't break the bank (Christmas is not far away...)
I wonder if he has de-snorkelled his car as well as fitted the TechnoTorque splitter?

08-17-2009, 05:23 PM	#12
Steve Tinker Registered User Join Date: Dec 2008 Location: Queensland, Australia Posts: 1,522	I love these discussions..... I'll go along with Pedro on dyno's & their operators. My experiences with dyno runs (mostly with motorcycles I must admit) is they are basically to give you just that - a baseline. Thats why SEVERAL runs must be made on the same day, preferably @ the same atmospheric temperature and humidity and (of course) on the same dyno. On road engines (but not race engines) the first run nearly always shows the lowest HP and torque figures because a) the fluids are not always up to a highe enough temp (especially the transmission oils) and b) the engines have usually a lot of carbon and oil buildup in the rings and valves from normal day to day running. Owners look shocked when they see chunks of carbon and soot emitting from the exhaust as their engines are opened up for the first time, quickly followed by the pall of oil smoke on the overrun after the first dyno run.... But its the 3rd or 4th hard run that gives you the baseline from which to compare engine outputs that really mean anything - that's when the engine is fully warmed up and the combustion chambers are cleaned out. Pedro may well be fine tuning the basic Porsche design and for the cost, it won't break the bank (Christmas is not far away...) I wonder if he has de-snorkelled his car as well as fitted the TechnoTorque splitter? Last edited by Steve Tinker; 08-17-2009 at 05:26 PM.