Bobbeh Posted November 18, 2005 Share Posted November 18, 2005 Im not knocking the hub dyno at all I've used Thors and I was impressed with the service, difficult to really compare with other systems, probably best to stick to a system and keep going to it when you make mods to really see the difference on the same system. Quote Link to comment Share on other sites More sharing options...
Pete Posted November 18, 2005 Share Posted November 18, 2005 Ok - easy answer to this one. Get a dyno tester that's calibrated somehow. Find a standard Supra and dyno it. Then take the engine out and bench dyno it. Compare the results to determine transmission lost. If you've done it great - tell us. If not, then stop wasting time guessing numbers. Has anyone done this? Is there a way of calibrating a dyno? Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted November 18, 2005 Share Posted November 18, 2005 All none inertia rolling roads and all engine dynos are easiliy calibrated 9and just as easily fiddled to give the figures the dyno operator thinks you want to see... I assume hub type ones have some sort of calibration method too, of course. Strain gauge types have a lever of fixed length that is inserted into the strain gauge mechanism and a known weight hung on it, and a potentiometer is used to make the starin guage show a particular voltage at that torque (dynos measure TORQUE, not BHP, the BHP is extrapolated from the torque figure). My Skyline engine gave X bhp on various rolling roads, and a LOT less than X BHP on a proper engine dyno... A hub type dyno, brand new, with the operator not putting in ny fudge factors got closest to the real figure, but not impressively close. Inertia type rolling roads are the most inaccurate, IMO. Strain guage torque loading tyre driven ones are more accurate, hub driven ones are OK, engine dynos are the real McCoy. Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted November 18, 2005 Share Posted November 18, 2005 Ok - easy answer to this one. Get a dyno tester that's calibrated somehow. -DONE Find a standard Supra and dyno it. - DONE Then take the engine out and bench dyno it. - it aint gonna happen. Compare the results to determine transmission lost. If you goto a dyno day where people are all driving supras then everyones gonna get lame figures if you think someones fiddling with them. Yet back in 2002 when about 12 of us got dyno'd at G-Force I dont think there was a single person questioning what was put out. Quote Link to comment Share on other sites More sharing options...
dangerous brain Posted November 18, 2005 Share Posted November 18, 2005 Our dyno at work had to be calibrated once every couple of months which was a pain as the weights we had to put on were 20kgs a pop and there was wedges of them. On and off 3 times usually to ensure that adjustments made at the top end didn't affect the readout at the bottom end. Our dyno was rated up to about 5000 shaft horse power That baby got so hot we had to have a huge cooling tower for it Strap your supe engine on there and watch that dyno yawn lol. Quote Link to comment Share on other sites More sharing options...
Gordon F Posted November 19, 2005 Share Posted November 19, 2005 The answer to the original question is 250rwhp for a J Spec TT. Mine was 249 and Brian Duffs (which was standard at the time) was 251. Done on a rolling road in Norwich around 2002. Matt Harwood brought his car and got exactly the same result as he had got at G Force in Aylesbury a week or so earlier. Quote Link to comment Share on other sites More sharing options...
Class One Posted November 19, 2005 Share Posted November 19, 2005 OK I got 262rwhp at Surrey Rolling Road with auto transmission. The only "mod" i had at the time was a foam green HKS panel filter. Everything else was stock. Quote Link to comment Share on other sites More sharing options...
Guest gzaerojon Posted November 19, 2005 Share Posted November 19, 2005 i got 328rwhp, as far as i know i got a filter, st'less exhaust with both cats and fmic (which i doubt would be working as it should with a couple of thors fans sitting in front) Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted November 19, 2005 Share Posted November 19, 2005 Thats not RWHP gzaerojon, thats hub dyno, which isnt the same as a rolling road. Its a shame about that panel filter doug, as it doesnt make the reading one for a stock car as much as you'd want it to be - its a good figure never the less Quote Link to comment Share on other sites More sharing options...
Tom Posted November 19, 2005 Share Posted November 19, 2005 321bhp and 255rwhp cat back exhaust running 0.75 bar(stock boost) manual. Quote Link to comment Share on other sites More sharing options...
Peter10654 Posted November 19, 2005 Author Share Posted November 19, 2005 Thx a lot again !! Peter Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted November 19, 2005 Share Posted November 19, 2005 321bhp and 255rwhp cat back exhaust running 0.75 bar(stock boost) manual. Is that a stock car, or a car with mods but running stock boost? 255rwhp is more like 310bhp. Quote Link to comment Share on other sites More sharing options...
Guest gzaerojon Posted November 20, 2005 Share Posted November 20, 2005 Thats not RWHP gzaerojon, thats hub dyno ok now im confused.. im new to all this dyno stuff and its the first one i've ever had.. i would've thought as the machines were hooked up to the hubs that would be the same as the rear wheels? i have no idea now:shrug: Quote Link to comment Share on other sites More sharing options...
Tom Posted November 20, 2005 Share Posted November 20, 2005 stock car bob, not for long though I hope! Quote Link to comment Share on other sites More sharing options...
Matt Harwood Posted November 20, 2005 Share Posted November 20, 2005 If you goto a dyno day where people are all driving supras then everyones gonna get lame figures if you think someones fiddling with them. Yet back in 2002 when about 12 of us got dyno'd at G-Force I dont think there was a single person questioning what was put out. The answer to the original question is 250rwhp for a J Spec TT. Mine was 249 and Brian Duffs (which was standard at the time) was 251. Done on a rolling road in Norwich around 2002. Matt Harwood brought his car and got exactly the same result as he had got at G Force in Aylesbury a week or so earlier. Yep, mine made 298 at G-force in Aylesbury, then 297 in Clive Atthowes in Norwich. That was running 1.2 bar, with FMIC, HKS exhaust, decatted etc. etc. That was with the auto. Then, a couple of years later, I put the manual on the rollers, (Same type as G-force in Aylesbury, but this time done at CPL racing in Sheerness). This time I got 348 running the same mods but with 1.3 bar and 650 injectors and E-manage. So 50 more rwhp for a manual transmission and slightly more boost/fuelling. Quote Link to comment Share on other sites More sharing options...
Chris Wilson Posted November 21, 2005 Share Posted November 21, 2005 ok now im confused.. im new to all this dyno stuff and its the first one i've ever had.. i would've thought as the machines were hooked up to the hubs that would be the same as the rear wheels? i have no idea now:shrug: The tyre deformation running on TWO contact patches in between the rollers adds further power losses, so that type of dyno gives a lower figure than one that bolts directly to the rear hubs. Quote Link to comment Share on other sites More sharing options...
Bobbeh Posted November 21, 2005 Share Posted November 21, 2005 stock car bob, not for long though I hope! I presume the info in your sig is not what you had when it was dynod? Quote Link to comment Share on other sites More sharing options...
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