my friend wont accept the potential of any car thats been set up on the roller, he says only cars set up on engine dyno's are fast, he rekons they cant spread the power when setting up on a roller! he has a problem with cars that produce peak power towards the end of the rev range!


is he talking shit? as im no good with all the setting up business i cant really disagree with him but always think hes wrong!

can you set up an identical engine the same on the rollers as a cell dyno?

he also only aknowledges flywheel power as rollers are rubbish, i dont agree with that at all, i only want to hear about wheel power!


cheers

 

Oh dear. I'll grab the tea and Hobnobs.

 

yes he's talking shit

 

FUCK... i knew it, just never disagreed, just told him i think he's wrong!!!!

 

shit, what have i done..... lol

 

he's obviously heard someone talk about it down the pub, misunderstood it, added his own brand of bullshit, then tried to explain it badly

rolling roads do have their limitations, but not being able to make a car go fast and having power in the wrong places is NOT one of them

 

he's basically heard something from one of his mates whos got a rs500 set up on the engine dyno by mountune and added his own shit!

 

both are not as good as a live map on the road imo

one of the main reasons being airflow its hard to get a fan big enough to feed the air to the intercooler so more likely to det, my own car made 22 bhp more just by being live mapped and that was by the same mapper

 

hmmmm and then theres a live map!!!!!

i've always prefered live map too! just from what i've read.

 

the only difference between a decent engine dyno and a decent rolling road are the transmission parts inbetween, ie the wheels, drive shafts transmission and clutch they both measure torque and power in the same way and assuming they are correctly setupo and calibrated there is no advantage of one over the other.

 

COMPLETEY DISAGREE, on the road you can not hold the load points very easily. Both an engine and chassis dyno can do this and REPEAT each point and CHECK for any losses or gains.

On the road, how do you know if you have made ANY improvements (unless of course you have "The King's" Arse Dyno ).

In my opinion, the car has to be set up accurately on a dyno (chassis or bench) and THEN checked on the road with the correct airflow etc to make sure all is okay (unless of course you have a chassis dyno that can accurately represent the airflow achieved on the road) .

 

nail on head rain bum

 

Mike sorry l had to edit it

 

thought you were only here to view Dave - not comment rofl

 

agree with the above about dyno vs road mapping. mapped on dyno checked on road.

loving the 'ass dyno' comments, would save us a fortune in my line of work, wonder if it has ISO 9001 approval??

 

View l could do without account, but needed to send pm's so hence this account. But will post every now and then and it looked like the time to post

 

it was on the rolling road before then perfected on the road

im not saying they don't have there place he got 22 bhp more on the live map than on the rollers main reason being no det

 

Why don't you just change your name back to what it was, so everyone knows it is you .

I know it makes a mockery of you spitting your dummy out and leaving, but hey hoe .

 

That's one accurate arse dyno, knowing exactly what was gained .

I think you're just confusing shit companies that haven't got a clue, to the usual top suspects .

 

If he got 22bhp more then he must have done a shit job to start with, so why if he is so good did he not just say rollers are pointless lets do it live map, more to the point why does he even have a very expensive rolling road when live map is better for him.
I'd go with rollers anyday as conditions can be set and engine listened to much better, cell temp can be what you want, so he set it for peak power on the road on a cold winters day, and a hot summers day you kill your engine with det or is that better.
Rollers have the REPEATABILITY that no one not even msd can match on the road, and can hold set rpm or speed or load, or mix all three, adjust temp to what you want, can't do it live map, live map optimised for that one days conditions, and nothing else, not at optimum, rollers are a average of ideal.
Most fans can produce 60mph with ease for the cooling.
tabetha

 

No Mad Yum is finished but might change my trident name

 

MAD Dave .

 

MAD Trident?

 

but you'll only get an "at the wheels" power figure on a rolling road
the same as you'll only get an "at the flywheel" figure on a dyno
and the same way you'll only get a "it feels like 500 bhp weeeeeeeeeeee!!!!!!!!!!!!!!!" down the bypass

 

Think it should be (Just Dave)

 

Or perhaps "Boomerang Dave" ?

 

with or without the brackets?

 

Without

And mike, dont know what you meanonly been once

 

the brackets wil make you stand out

although i'm not sure that would be a good or a bad thing

 

they are all just tools to get the job done!

 

Thing is, an engine dyno for example, is more accurate than you could typically show with any aftermarket ECU.. so the question of "can you set them up the same on an engine or chassis dyno", the answer would have to be yes.. (assume a steady-state chassis dyno)..

Ultimately though, an engine dyno is better. It's a much more controlled environment and is ideal for R&D & mapping.

As above though, everything should be checked thoroughly on the road too.

 

thanx!

this is what i wanted to know!

 

has anyone got a power graph of an engine measured on a engine dyno?

when you do a power run will the reading be similar in the sense that the peak power will be made and dropped of at the same..ish revs? (taking into consideration power is measured at differnt points so final power will differ)

 

Engine dyno for developement and measurements

Rolling road for set up in safe environment

Road for driveability and final real life adjustment

The way 100% of manufactures carry out their powertrain development!

 

 

so please tell me, what would the same cars power graph look like if it was run on rollers for a power run?

 

Peak power could actually be lower as the gearbox efficiency changes with speed and load.

If the friction rises with speed to quickly in a transmission then the power towards the higher RPM sites can read low.

 

when you measure power at the flywheel you have only the internals of the engien that cause a sapping of the pwoer

when you measure the pwoer at the wheels, you have to take into consideration a lot of losses through the transmission as in the clutch, the internals of the box, the prop, the diff, the cv joints and even the wheels all need power to make them turn, they don't just transmit the power wihtout requiring some of it to turn themselves so it's mroe of a guestimate at what the engine is actually producing

 

nice one!

with the graph above can the same power curves be achived on a rolling road? the answer to that could be the end of my thread.lol

 

And it is easy to cheat a power run and have a high reading.

An engine at full throttle doing a quick power sweep up the rev range reads differently to an engine having steady state readings.

Its easy to get another 30% more torque on engine dynos by simply using the dyno to load the engine up to slow it down. Not only does it read the engine torque but the torque required to slow the engine down.