Dyno chart and shift lights

[jerrytlr]

Hi all, had a thoroughly good blast in the T350T yesterday :-)

Was wondering if anybody had a dyno chart for a standard car that I could use to set sensible values for the shift lights? I was thinking something along the lines of:

Green - about 500rpm below peak power, get ready....
Amber - about 500rpm past peak power, best to change now!
Red - about 500rpm before limiter, what are you playing at??!!

However the 500rpm is a guess, I would like to see where peak power really is and what the shape of the curve is before choosing the best values to use


TIA for your help

Cheers,

Jerry

[madbadger]

My peak is at 7390.



I've got the red at 7400, so about 1000+ from the limiter.

My amber is 6900 and green at 6000.

[t40ora]

Haven't dyno'd mine, but Phil at Racing Green said that peak is usually about 5800. So my lights were set at 4800, 5800 and about 6200.

He reckons (and as he's a racing driver I believe him) that is the best band to be in for very quick progress.

BUT....as I said, haven't had mine dyno'd.

Edited by t40ora on Sunday 10th December 11:58

[madbadger]

Seems low. Did he mean Torque?

As I understand it you can rev up to the peak bhp. Don't see the point of going up to the limiter as the power drops off before then.

IMO at 5800 you are missing a world of giggles. I'd more see the point at 6800 when the Torque is done.

[Fly Boy]

I think he meant torque

Don't forget the old adage

Horsepower sells cars, torque wins races....


I have my green set at 4000- fr when the oil is still cold

[madbadger]

Fly Boy said:

Don't forget the old adage

Horsepower sells cars, torque wins races....

It's good to torque.

[jerrytlr]

madbadger said:

My peak is at 7390.



I've got the red at 7400, so about 1000+ from the limiter.

My amber is 6900 and green at 6000.

Many thanks for posting this - exactly what I was after - although it is a bit odd that the dyno operator didn't run the test a bit higher up the rpm range so we could see what happened to the power post-peak. This is important as if it drops off very suddenly it is best to change gear at the peak, if it stays high for a while post-peak-power then it is best to hang on to the gear until you are past the peak - the idea is to get maximum area under the graph for each successive gear, to do this you need to know the shape both before and after peak power...

I once had my bike dynoed and the operator did a 2-3-4-5-6 gear run which was really interesting, as it showed this principle perfectly. The bike was a TL1000R which hit peak power at about 10K rpm (120bhp at the wheel) but was still above 115bhp at 11K rpm. To get maximum acceleration (ie max area under the graph through all gears), you needed to change at about 11K - which meant disabling the first stage of the rev limiter :-)

BTW what is the rev limiter set to on the T350?

Cheers,

Jerry

[madbadger]

I was a bit surprised he stopped there too. I think he was worried he would go deaf. It doesn't look like it is about to plummet.

I think the limiter kicks in at 8800.

[targarama]

I didn't have mine run too high, but as you can see HP was still chugging along nicely where the graph ends. Torque peaks earlier though at 6456rpm - so just after this would be the optimum shift point. My shift lights are set at something like 6,000 then 6,500 then 7,000. I rarely see the red light, especially at this time of the year.

I'm considering buying something like a Fiat Panda 100hp thing for fun as it is virtually impossible to use all of the TVR's performance on a public road in the South East of England. Obviously as an extra car, it wouldn't replace the TVR.



Edited to say, yes my torque figures are extremely high - too high to be right maybe, take some off if you like, the car still goes like stink.

Edited by targarama on Saturday 9th December 17:26

[jerrytlr]

targarama said:

I didn't have mine run too high, but as you can see HP was still chugging along nicely where the graph ends. Torque peaks earlier though at 6456rpm - so just after this would be the optimum shift point. My shift lights are set at something like 6,000 then 6,500 then 7,000. I rarely see the red light, especially at this time of the year.

I'm considering buying something like a Fiat Panda 100hp thing for fun as it is virtually impossible to use all of the TVR's performance on a public road in the South East of England. Obviously as an extra car, it wouldn't replace the TVR.



Edited to say, yes my torque figures are extremely high - too high to be right maybe, take some off if you like, the car still goes like stink.

Edited by targarama on Saturday 9th December 17:26

Thanks Targa - Looks like keeping it between around 5.5Krpm and 7.5Krpm would be best for max acceleration - not sure what the gearing is like but would expect that changing at just over 7K would work well, so that's where the orange light should go IMO...

Cheers,

Jerry

[targarama]

To be honest, a few hundred revs here or there won't make much difference unless you're on the track, these cars are more than quick enough for the road without worrying about gearshift technique etc.

[T66ORA]

targarama said:

To be honest, a few hundred revs here or there won't make much difference unless you're on the track, these cars are more than quick enough for the road without worrying about gearshift technique etc.

Agreed, i take it, Jerry you don`t own a S6 yet? In the real world changing up at approx 6k rpm is enough to destroy 99% of cars on the road, including all RV8 Tivs
For what it`s worth my car`s max power was at 6600rpm and max torque at 5250,the rev limiter is set at 7800 rpm, which you will probably never hit regularly, the torque graph is almost flat from 5k to 6500 rpm, my figures where taken at the WHEELS at Pauls (Austec) new rollers, the old ones where a little optimistic apparently

[jerrytlr]

T66ORA said:

targarama said:

To be honest, a few hundred revs here or there won't make much difference unless you're on the track, these cars are more than quick enough for the road without worrying about gearshift technique etc.

Agreed, i take it, Jerry you don`t own a S6 yet? In the real world changing up at approx 6k rpm is enough to destroy 99% of cars on the road, including all RV8 Tivs
For what it`s worth my car`s max power was at 6600rpm and max torque at 5250,the rev limiter is set at 7800 rpm, which you will probably never hit regularly, the torque graph is almost flat from 5k to 6500 rpm, my figures where taken at the WHEELS at Pauls (Austec) new rollers, the old ones where a little optimistic apparently

Erm - yes, I do own a T350T - and in the 500 or so miles I have driven it so far, I have NEVER driven it flat out - so my questions are a bit academic - I just like to get things set up properly. I know that's a bit nerdy, but there you go :-)

Thanks for the definitive answer on the rev limiter as well.

Oh, and before buying the 350, I was torn between it and an immaculate, late model Chim 450. I test drove both back to back and, even without really ragging the 350, it was abundantly clear which was the faster car :-) The Chim was great, a fantastic experience, but nowhere near as much of a drivers car as the 350....



Cheers

Jerry

Edited by jerrytlr on Saturday 9th December 18:57

[T66ORA]

jerrytlr said:

T66ORA said:

targarama said:

To be honest, a few hundred revs here or there won't make much difference unless you're on the track, these cars are more than quick enough for the road without worrying about gearshift technique etc.

Agreed, i take it, Jerry you don`t own a S6 yet? In the real world changing up at approx 6k rpm is enough to destroy 99% of cars on the road, including all RV8 Tivs
For what it`s worth my car`s max power was at 6600rpm and max torque at 5250,the rev limiter is set at 7800 rpm, which you will probably never hit regularly, the torque graph is almost flat from 5k to 6500 rpm, my figures where taken at the WHEELS at Pauls (Austec) new rollers, the old ones where a little optimistic apparently

Erm - yes, I do own a T350T - and in the 500 or so miles I have driven it so far, I have NEVER driven it flat out - so my questions are a bit academic - I just like to get things set up properly. I know that's a bit nerdy, but there you go :-)

Thanks for the definitive answer on the rev limiter as well.

Oh, and before buying the 350, I was torn between it and an immaculate, late model Chim 450. I test drove both back to back and, even without really ragging the 350, it was abundantly clear which was the faster car :-) The Chim was great, a fantastic experience, but nowhere near as much of a drivers car as the 350....



Cheers

Jerry

Edited by jerrytlr on Saturday 9th December 18:57

Good choice IMO It takes a few miles to really appreciate the cars capabilities, and at this time of the year the rev limit is normally 4000rpm Be careful, third gear fish tails can occur with out restraint of the right foot.

[t40ora]

T66ORA said:

targarama said:

To be honest, a few hundred revs here or there won't make much difference unless you're on the track, these cars are more than quick enough for the road without worrying about gearshift technique etc.

Agreed, i take it, Jerry you don`t own a S6 yet? In the real world changing up at approx 6k rpm is enough to destroy 99% of cars on the road, including all RV8 Tivs
For what it`s worth my car`s max power was at 6600rpm and max torque at 5250,the rev limiter is set at 7800 rpm, which you will probably never hit regularly, the torque graph is almost flat from 5k to 6500 rpm, my figures where taken at the WHEELS at Pauls (Austec) new rollers, the old ones where a little optimistic apparently

So maybe I got the numbers a bot wrong, but just to confirm - ragging it to the red line is not necessary then? Tony, you reckon red light just beyong 6600 will do, maybe less than your 7800?

If I want to be negative about myself, I'm a bit overcautious. In positive speak terms, I have lots of "mechanical sympathy"! I want to get the best without being silly.

So where do you recommend green and amber lights to be set?

[willyworm]

Amber 6000 and red 7000, you will find little extra performance for road use if you go any higher, and it
does give the engine a bit of sympathy. Sometimes you will need the extra revs to beat another car but very rarely.

[t40ora]

willyworm said:

Amber 6000 and red 7000, you will find little extra performance for road use if you go any higher, and it
does give the engine a bit of sympathy. Sometimes you will need the extra revs to beat another car but very rarely.

Makes sense. And green set either low during the winter as a number of peeps have mentioned, or about 5000. Dunno if it's just me, but 500 revs whiz past damn quick so I need a gap of 1000 else it's all a bleedin' blur of coloured lights....