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Not looking for max power, although I disagree. My car has dyno'd on an inground dynojet from Georgia in Georgia and a portable dynojet from California in Ga in the same week, same conditions, same correction factor within 4 whp, and one was heat soaked right off the track, sat running for 20 minutes with no fans. It has also within the last 8 years always dyno'd within 4-5 hp on different dyno's. Repeatable results are what matters to me, what that means as far as speed is completely debatable though and doesn't really matter (to me).
What I look for is more detail, how much does hp fall off as car heats up. How quick are you reaching power, how is power holding to redline, how steep the torque/hp curves are. As a road racer I have to look at much more than that as 60-130 is only a few seconds out of a lap for me.
Yes I agree and I hear you and I did say dynos are good for TUNING. I will do up a chart calculated from the vbox verify which will show a chart like a normal dyno. What I am saying here is my power across the board is up in every gear. Instead of spooling above 3000 rpm I now get boost as low as 2200 rpm and apart from 6th gear (what is that for again ?) Tim has tuned it to be better across the board.
I should add from datalogs my IATs are barely rising at all because I have ETS Intercoolers which have been shown in threads here to be epically good. When I drive my car on these high speed runs it is not a one off. I do about 100 miles a day when I do them and rattle them off one after the other, no cool down, no data manipulation. I was doing 0-150 mph and then a hard thrashing on a few dedicated 60-100 and 60-130 and the times were similar and the vbox acceleration charts show similar power at similar speeds.
I do not track this car yet and will not until I get an LSD and feel 100% comfortable with what I am doing.
If I weaken I will take her and get a dyno (I feel jinxed cause I have only seen 2 cars dynoed, one was mine which broke and the other in UK actually took off)
Here is one datalog where I aborted at 5000 rpm in 3rd gear because of traction
I would think there are other factors in place that will effect acceleration and make horsepower difficult to measure in road conditions.
Air resistance and tire traction.
Read what I wrote, you measure it many times many many times but my times are indicative of what they are.
I should also add that I have programmed in other dyno charts from a lot of the vbox verify charts here at 6speed and at dragtimes and used those to calculate power on cars like the SpoolBus, BHT, Fikse's McLaren 12C, Xbox's 997.1, Mikes A28 996 Turbo, some of Emre's Porsches and some others. Some cars are within a few % of my calc based on their dynos and some cars show dyno whp which are 200 hp higher then their best ever recorded accel times and calculations. Ironically, the latter usually show times which reflect the lower vbox verify horsepower than those off their one of dyno pulls, ie their dyno nos were bulldust.
Last edited by wolfhedge; Oct 30, 2014 at 10:00 AM.
My table above is what the hp calculated from specific runs based on the vbox data.. there are anomalies but over an average will give a good guide. Tim's car dynoed at 1288 whp and on his 227 mph Texas run early this year showed actually a lower expected output. Mine shows anywhere from 680 crank to 750 crank (allowing for the 10Hz sampling rate of the sat and vbox there will be errors) but across a statistical sample it will give a very close guide. Another measure is to datalog your actual load % against rpms and do the old
HP = Torque x RPM ÷ 5252 which for mine shows around 700-720 hp crank at 6000 rpms or so
Switched back to 93 octane when I got back to my house today as I thought the extra spool and power from the E85 was dangerous given my tire slip... nope slips like hell in 3rd, 2nd and even 4th gear sometimes... just waiting on my Toyos or PSS2's, whichever they get in stock out here 1st but
I did another 4th gear run with a very low 100-200 kmh on just E20 (mainly 93 octane and a teensy 1.5 gallon left over ethanol).. implying a 6.7-6.8 sec 60-130 mph time on only E20. I will post it up when I get the vbox from my SD card.... I think with new tires and my E85 tune we can go 6.4 seconds on my -2% slope... once the deer get killed off before Dec.
The times for my 40-80 mph with the 93 octane tune are much slower with the spinning tires = 3.3 secs instead of 2.97 secs (spinning tires as well).
The 93 octane tune Tim941 did with the Eurodyne is perfect... I just got the tank down to empty, added the 93 Hess and reflashed the car in all of 3 minutes..
I have about a 1000rwhp and did 4.21 sec with 1 shift on a 3.6L...
__________________ 2001 996TT3.6L and stock ECU
9.66seconds@ 147.76mph 1/4 mileclick to view 160 mph @ 9.77 seconds in 1/4 mileclick to view 50% OFF ON PORSCHE ECU TUNING BLACK FRIDAY SPECIAL
Maxxed out turbos and clutch and tires so now time for the next slippery slope.... oh it is a never ending web we weave.... switched back to 93 octane on Fri but tires still spin like crazy... was going to put on PS Cups or Toyos as I can get those now but the temps here are already in low 30's in mornings and sub 50's during day...meh because I hear neither of those tires is any good under about 50F so I doubt at 40F and below we could get enough heat to warm them up.
Should I just get another set of stock wheels and add some all season tires for winter ?
Last edited by wolfhedge; Nov 9, 2014 at 07:21 AM.
Maxxed out turbos and clutch and tires so now time for the next slippery slope.... oh it is a never ending web we weave.... switched back to 93 octane on Fri but tires still spin like crazy... was going to put on PS Cups or Toyos as I can get those now but the temps here are already in low 30's in mornings and sub 50's during day...meh because I hear neither of those tires is any good under about 50F so I doubt at 40F and below we could get enough heat to warm them up.
Should I just get another set of stock wheels and add some all season tires for winter ?
turn the power down, run 93 oct and use winter tires on pos rims for the winter. save the power tires and money for the spring. btw toyo r888 aren't made in 315 any more
