I remember reading somewhere on this site, that most tuners map the top end out on the road and not on the dyno...Im just curious to why that is??

 

* gets ready for 10 pages *

 

It's usually because the people concerned do not have a dyno.

 

I think you are getting confused with "mapping" and "checking".

Mine was mapped on an engine dyno, and then all the low speed / cruising maps were done on the road (on the way to and from Bruntingthorpe), where the fuel / ignition and boost maps were checked and adjusted as necessary whilst running absolutely flat out in fifth gear. Now considering the speeds reached (175mph), I certainly would NOT want to being checking that out on the road .

 

Pussy!!!!!!!!!!!!!!!!!!!!!!!!!

 

some dyno's don't 'load' the car enough, its always worth checking/readjusting on the road.

 

I find your comment ironic considering your post about Russel Brand / Jonathan Ross . It's all about respect for other people's lives .

 

if your doin speeds like that on a public road then sorry but your a accident waiting to happen lets hope you don't take some innocent person with you

 

Where did he say public roads you fooking do gooding nancy boy.......I'll bet my ass Rod's is mapped at Brunters or similar

 

this leads me to think that and read what i said i put IF

and why am i a do gooding nancy boy

 

What? I think you have that a bit backwards. Engine dynos load the engine fully, this is how they hold them at a given speed.

As Mike Rainbird says, they're generally checked on the road, as things can change from the dyno to the car (eg, the installation) and any fine tuning to the maps can occur.

 

I think Guzzler refers to rolling road as a dyno - as in "Chassis Dyno".

 

Well even a steady-state rolling road (chassis dyno) is effectively an engine brake so produces maximum load. Only inertia style rolling roads may not.

 

not in all cases

 

you better buy a new one then!!!

 

i never had that problem, spoke to a few people who have though

 

 

Another plus on the engine dyno side is all the temps are constant oil water intake ect ect , plus as said before if anything does go skyward its better it on the dyno that up and down the local bypass you pays your money you take the choice

 

When i said `dyno`, i actually meant to say rolling road.

No i did mean to say mapping. Ive heard some tuners say they do most of the map on the rolling road then the very top end(high rpm/max boost) is done on the road while flat in fifth!
I would have thought that a good rolling road would have enough braking effect to load the car enough at 175mph. Is it due to lack of airflow on a rolling road to keep temps down?

 

Most rolling roads have a limit for maximum speed - it's becase of the balacing of the rollers etc. For example the one we have at 4Turbo is limited to 220kph (from memory). It does not mean it won't work over that speed but it isn't entirely safe to do that. Still it's not a problem as you can map the car in 4th or even 3rd with enough load to simulate driving to the top of 45 degree slope in 5th flat out.

The thing is you will still want to check the performance and data in real world. Sometimes it can hit some peculiar point in the map only on one track, road or in one situation and give a problem. We had this with one Evo 9 which was getting knock on road fuel only on one particular circuit and this was not possible to replicate on rollling-road or highway. We never got opportunity to track it down completly but it seems it was due to immense heat soak on the track on a hot day with several consecutive fast laps.

 

Well ive not actually had a fast car for three years but yes guilty of crazy speeds in my time. Admit to speeds approaching the magic 2 some time back as a few on here can testify. My comment to Mike was a joke as he very well knows , my car is checked at Brunters, but is rechecked under public road conditions when of course we never exceed 70mph .

 

oh god here come the do-gooder comments from people who toodle about at the speed limit

 

my cars mapped on the road at a good 170...............and i must say it's VERY easy to do those speeds on the road.............kph for the "i never go over the limit" possie.....

 

If the DYNO you are using does not apply enough load for the engine then you need to use a better one