Dyno sheets and discussion for UK Rotaries!

[scooby_si]

but as mentionned previously all we have from the Nobles RR day is ATF & i\'d rather rely on there accurate figures (yeah thought i\'d start a dyno accuracy debate with that wording lol) rather than just using a standard theory/formula to work out RWHP possibly with more inaccurracies......http://www.smileycentral.com/?partner=ZSzeb008_ZNxdm46052GB\' target=\'_blank\'>http://smileys.smileycentral.com/cat/29/29_1_5.gif\' border=0>
Ho hum no fun if it\'s easy should be our moto :rollin
Si

[Smifta]

Originally posted by scooby_si
rather than just using a standard theory/formula to work out RWHP possibly with more inaccurracies......
Correct me if I\'m wrong, but surely Noble\'s only came to your figure by using a standard theory/formula.

Perhaps someone should find out \'what\' formula they used? (unless I\'m talking out my botty, and they use the run-down method).

[scooby_si]

they told me the figures were using the -ve load kinda thing which i presume is the "run-down" method & that they couldn\'t caluclate it back with a standard formula as they vary from car to car. Seemed a little weird they couldn\'t just whack the actual power at rollers on too but hey only going on what i was told & i still like my lill graph either way.....
Si

[RE:Worx]

What dyno is Pip getting? I vaguely recall Dom from Dyno Dynamics mentioning Pip so may be its a DD too? would be nice if there was a DD up that way...

[gsb876]

Not sure which Dyno Pip is getting, once i\'ve been i\'ll let you guys know.

[Carl]

Pip is getting the Dyna pack hub dyno.These are a very good tool and very kind to your car,they use windows software,and are not Dos based.
Regards
Carl

[20B_boy]

Yeah, Geff said yesterday, DD were abit slow with the hard sell apparently

Windows software - hope the IT geeks arent reading this! :rollin DD will soon be susceptible  to the Windows patented \'blue screen of death\' too as they have Windows software being finalised atm. Hopefully it wont be a compulsory \'upgrade\'! ;-)

Every one has a preference I guess, Geff and Phil have used Abbey and CPL more than most here and decided the Dyno Dynamics was theirs. Geff was introduced to the DD when he went to Aus with MicroTech in 2003 and was very impressed. He used Jon at RX Engineerings Dyno Dynamics. Either way, a dyno is a very useful tool to have in your workshop as you say Carl...

Other people who use Dyno Dynamics (extracted from our website) just for the sake of it:

Maztech
Mazfix
Dalton Automotive
Dyson Rotary
Rotormaster
Selectmaz

Be very happy if we get any where near replicating any of those guys achievements in the future, LOL!

[g11ary]

Just flicking through here the other day and Ive been moved down to 9th but should be in 5th just above Ant, some pages ago my dyno at the hubs was 365
And Gurj in 6th is at the fly?

[20B_boy]

My attempt is temporary but is easy to update so if any one wants it changed then just let me know.

Gary - no offense - I\'m sure a few of the entries are wrong! I\'ve moved you back up to numero 5. The reason Gurj is their with FWHP is that no one seems to want to agree on a conversion factor between W/F/H power - so I just listed them \'as recorded\' and indicated whehter W/F/H...

[sdminus]

It all looks very good but weather its fly or wheel seems irrevant really. It should all be on a even keel either fly or wheel not both. Also i would think that dyno figures should be backed up with accurate graphs from calibrated dynos to count.

May well be wrong but just my feelings.

[g11ary]

can see where the confusion is, I think Glen converted my hubs to wheels as I think thats what he wanted to get to, now is a mixture, fly obviously lower thats why I noticed it. Regardless of conversion factor if its wrong everyones would be wrong by the same amount but should probably convert everything to fly as must use it (and its bigger)

I think all figures on  here have been provided by sheets via the owners or the tuning companies doing them.

[PETE SMITH]

"dyno-dynamics" and "Flywheel" seem popular-converting the rolling road "at the wheel" to "flywheel" seems ultra simple if you\'ve got the right equipment.
Though i agree boost bar IS a major factor when comparing RXy\'s.
Pete:)

[20B_boy]

Its easy to just use a deemed loss to convert from wheel to fly (for e.g.) - its a matter of agreeing what the conversion is tho or half those on the forum will be unhappy - you lot decide! We used to use a fixed 18% loss to convert from wheels to fly power, but that may or may not be accurate (unlikely) - and for a fact some will disagree strongly. You\'ll find umpteen different opinions as to how wheel/whatever power etc relates fly/whatever power.

Far be it from me to decide whats \'right\'.

[PETE SMITH]

IMHO,
It\'s fairly clear from the list that the significant factors seem to be:
1-whether it\'s ported
2-Is it a Phallic Toe-HKS or maybe the BB Garrett?
3-Non sequential Twins have a part too
4-If your Rexy is for straight 1/4 mile burn\'s, reliability is less of an issue
Unlike piston/conrod/cam non rotary engines, the reasons for differences in performance is simpler to see.
Maybe i\'m talkin a load of testicles:D :rolleyes:
Pete

[banned advertiser]

Originally posted by petemillis
Most consistently reliable conversion factors I have found for a rear wheel drive are as follows.

RWHP +10hp to arrive at ATH HP then take into account 12% loss from fly to hubs by dividing by 0.88.

So, 250 rwhp + 10 hp  = 260 ath hp
      260/0.88 = 295 atf hp

Going the other way 295 atf hp - 12% = 260 ath hp
260 ath hp - 10 hp = 250 rwhp

Rich, you are the number cruncher.
can the sums above be worked out into a percentage, or just use whats a simple calculation like this one if it is the accurate.

Then can we all argree that figures to be quoted are fly.

If others disagree later, well tough you could change things constantly, were not looking for accurate we want something comparable. The other important items also that Pete put forward such as porting, psi, turbos etc can also be added .

At the end of the day it should be more fun than anything else.

The biggest bhp may rebuild every race, but bhp blown up on the dyno dont count, it must at least drive home or somewhere. Its all pub talk (where\'s danny when you want him)