Dyno sheets and discussion for UK Rotaries!

[J4P RX]

Presumably a real 170 is also going to be very different to a stationary 170 though, unless you have enough fans to produce that sort of windspeed?

[jonyb]

All down to the tuner i suppose, although i can see where you coming from.
As it was group dyno got to the numbers and happy to drive home.

Carl,

Andrew with the 02 spirit ( i think you serviced it for him) got 255@hubs (ex factory 280fwhp) ....he was happy with that i think. Just for info.

J;)

[Carl]

Originally posted by jonyb
All down to the tuner i suppose, although i can see where you coming from.
As it was group dyno got to the numbers and happy to drive home.

Carl,

Andrew with the 02 spirit ( i think you serviced it for him) got 255@hubs (ex factory 280fwhp) ....he was happy with that i think. Just for info.

J;)

But remember that the 280hp is the agreed limit from the japanese manufacturers,so in all likelyhood the spirit has more than 280 flywheel.
Andrews car is on a stock ecu still too.
regards
Carl

[20B_boy]

Originally posted by Carl
Well your car should be reliable since it has been mapped at ReWorx.
The reason that we map to a high speed should be pretty obvious really,the car is not limited to only 120mph so the tuning should be done at the limits of the car and not the dyno whatever the hp you require.After all,how many people only drive their car to the redline in 3rd gear?especially on track days.

The dyno hub puts plenty of load on the engine but enables all of the gears to be properly tuned,if the engine is only tuned in 3rd gear then the turbo will come on boost differently from 4th and 5th and in those gears the tune may not be as safe,But I would have thought that any good tuner would know that.
Regards
Carl;)

In case it isnt evident I dont do any tuning for RE:Worx! :confused:

Carl,

I dont see how road speed correlates to load and thus why you need to tune maximum load at 170mph. My understanding is this (ltd I grant u!): the ECU determines ignition and fuel settings at any given time by looking up the current engine load (which it uses the MAP sensor to measure) and referencing it to engine rpm. How does the amount of timing or fuel required at a certain engine load vary with road speed? isnt the timing and fuel the same for a given load, whether you are in 2nd or 5th? the boost pattern will vary loads but the ecu will look at the same values in the MAP to determine what it does - theres no gear or road speed correction? so what does it matter which gear u tune in as long as all your loads sites are covered - which they will be - ? I\'m confused. I will ask Max later, I\'m sorry if I\'m missing some thing.

Hopefully some one else finds this interesting too!

R.

[88GT-R]

Originally posted by 20B_boy
In case it isnt evident I dont do any tuning for RE:Worx! :confused:

Carl,

I dont see how road speed correlates to load and thus why you need to tune maximum load at 170mph. My understanding is this (ltd I grant u!): the ECU determines ignition and fuel settings at any given time by looking up the current engine load (which it uses the MAP sensor to measure) and referencing it to engine rpm. How does the amount of timing or fuel required at a certain engine load vary with road speed? isnt the timing and fuel the same for a given load, whether you are in 2nd or 5th? the boost pattern will vary loads but the ecu will look at the same values in the MAP to determine what it does - theres no gear or road speed correction? so what does it matter which gear u tune in as long as all your loads sites are covered - which they will be - ? I\'m confused. I will ask Max later, I\'m sorry if I\'m missing some thing.

Hopefully some one else finds this interesting too!

R.

Hi Rich,
Load points in 4th gear will differ to load points in 5th gear, same as the difference between 3rd and 4th. Part of this is due to the time difference taken to cover the effective rpm range, and the amount of load asserted over the same area.
For instance, say an engine´s peak torque is found to be at 6000rpm. Peak torque being the highest load point, and most probable point for detonation. As the engine accelerates through this point, a tuner might not notice an increase in Knock or hiccups in fueling. If he were to tune the car in a higher gear, the time spent over this range will increase thus improving the chances of tuning out any anomolies.
The tuner may wish to hold the dyno load at this point to simulate this effect in a lower gear, but ultimately will not give a true representation of the load characteristics experianced in the higher gear. Chassis dynos should be used to suppliment ones tuning methods, not determine them.
Most common enviroments for tip failure are on the road and in the higher gears, accelerating through the engine´s peak load point.
Sorry for the long winded reply, i hope that it may be of some help.

John

[Carl]

Originally posted by 20B_boy
In case it isnt evident I dont do any tuning for RE:Worx! :confused:
R.

It is,don\'t worry.

See what John has said.
Thanks John for explaining the reasoning.Also if you map only in one gear then you are likely to end up with parts of the map that have not been tuned,eg a high gear at low rpm will end up in a part of the map that a mid gear will not.You still have to input the data to control the event correctly so that when the ecu detects those parameters it knows exactly what to do.
Regards
Carl

[maximtaylor]

Yup, just found this thread. I agree that the longer you spend going through a cell, the greater degree of finesse you can apply. A/F correlation to the cells in question is more accurate, and so is the volume of information you get in feedback.

The cells you pass through also vary slightly, a slower pull goes through into boost cells far earlier than a regular shootout power run, although once you hit the peak average boost cells, the journey across the rev range is as before.

This can be mimicked on many dyno\'s by adjusting the ramp rate manually, effectively giving the same slow rate of acceleration and loading that a higher gear would give. Two ways of reaching the same result.

Good cooling fans are a necessity for this!!! The extra load turns the rotary engine into a very effective kettle

Off to play fireman now, cheerio!

[20B_boy]

Thanks guys - I like to learn

So you can achieve the same thing by adjusting the ramp rate - I figured that if my knowledge and logic failed that there must be some way of replciating the afforementioned conditions or some of big guys who tune on DD\'s, err, wouldnt!

[PETE SMITH]

Ooo, this is a bit technical for my addled brain!
It reminds me of Treadmill tests for people with dodgy hearts!:eek:
The correlation for the RX is scary!
Most people with Angina are smokers-BUT ALOT ARE GENETIC LINKED- they give out lots of emissions from there Tabs...a bit like an RX....And they both eventually need a rebuild!..I suppose Coronary artery grafting is a good quality Port!!:p
Pete
BTW, i smoke cigars..:o

[John Yorke]

[
Pete
BTW, i smoke cigars..:o [/B][/QUOTE]

Tut tut Dr Pete:D
How can you face your patients having partaken a lar-de-dar:bandit

PS Find this part of the thread very interesting

[PETE SMITH]

Mints and aftershave!:p
though, you must remember some people we see, don\'t alf honk!
Pete

[MikeLMR]

how do these different types of dyno\'s work then ?

I know some use a rotating mass and just work it out by how quickly it can be accelerated but then I imagine thats not the best thing for actually mapping an engine ?

I\'m not 100% sure but the  water brakes we use at work vary the load to hold the engine at a constant speed and calcuate the power from that.

And how do you calibrate a rolling road ? I can see how you can make sure the rotating mass ones a pretty much spot on by making the flywheel arrangment accurately but the brake type would require somthing of know power output to calibrate it

[maximtaylor]

The dyno dynamics type uses a system similar to a Telma (electromagnetic retarder) on a LGV Mike.

How it is initially calibrated, I\'ll find out.

I think the Dynapak uses fluid?

[g11ary]

Originally posted by 20B_boy
Thanks guys - I like to learn

So you can achieve the same thing by adjusting the ramp rate - I figured that if my knowledge and logic failed that there must be some way of replciating the afforementioned conditions or some of big guys who tune on DD\'s, err, wouldnt!

So do all the DD\'s have the same limitations or are the big boys using bigger better DD\'s.

Is that like comparing it to a folk lift, and a ramp
both will lift the car, only one better and possible without damage.

[Carl]

Originally posted by maximtaylor
The dyno dynamics type uses a system similar to a Telma (electromagnetic retarder) on a LGV Mike.

How it is initially calibrated, I\'ll find out.

I think the Dynapak uses fluid?

Hi Max,
The type I used the other day works similarly to the DD,but there is no "flywheel effect" from the weight of the rollers themselves that can affect the way that the rollers act upon the rest of the car when going through the gears.Of course when holding a point then that will alleviate that.

Hey Rich,
Come on,I am sure that you know how your equipment operates,and don\'t need Max to explain it on here since he is working for you.
Regards
Carl:rollin