DYNO RUN STD CAR

[Spike]

Lots of interesting comments coming out, also lots of thoughts of dyno shoot outs and power figures.
an interesting point though i will make about dyno sheets and dynos. the sheet that TRW1 has posted is the sort that i would avoid like the plague ( sorry and dont take it personal) if you look at the figures and do the calcs this dyno sheet is actually correct, however, the scales on either end do not corespond in number value! this gives an odd looking graph to anyone with a trained eye as the torque and horsepower DO NOT cross at 5252 rpm. now let me say again that i have looked at this and run the numbers and it is correct, and impressive but is showing just another way to cloud the issue with a dyno sheet.
the numbers are of course: horsepower = torque multiplied by rpm divided by 5252.
by using different scales the comparison against dynos that do use the standard layout gets confusing and is open to some folk to falsify the results by manipulating graphs, as i said, this has not been done here.
another way of falsifying the results is to hike the dyno electronics temp up, this gives the sae calculation the wrong temp as to mis quote at the standardised temp (20 degrees c)
also some dyno operators alter the drum weight within the computer programe data, telling the computer the drum is heavier calculating the horsepower UP!
all these things are happening and are at various places i am not prepared to divulge but are known as SMILEY DYNOS, buy us in nottingham.
i will say again though impressive figures just with a sniff!

It's always bhp people look at but I'd rather have more Torque.
Tim's 240ft/lbs is impressive against what standard cars really make and is why it's so 'quick'
Generally, bhp will improve your top speed and torque will improve your acceleration.

When I had a 50bhp nitrous shot my peak torque was 332ft/lbs@3200rpm. [smilie=icon_eek.gif]

Graph shows figs at the wheels.

 

[TRW1]

I agree Spike, an operator can write his own ticket, literally.


In this case a "sniff" of laughing gas perhaps?

 

[Spike]

I agree Spike, an operator can write his own ticket, literally.


In this case a "sniff" of laughing gas perhaps?

i only need to convince the other 1000 or so.......
yes a real laugh!!!!!!!!
i assume these figures were at the wheel, what sort of dyno is it?
and did it use eddy current in any way?
also, how bog stock was the motor? makes mine look sick!

 

[TRW1]

I'm not sure on the specifics of the Dyno Spike, that's starting to go over my head........
Figures were at the wheels, so approx 186 for a Mk1 as opposed to your 207 for a Mk2.
(for the layman) Figures quoted in print were those derived from calculations as discussed earlier in the thread, the headline 232.1 was on gas at the wheels......
Motor was standard at that time except for pipercross and quicksilver backbox.

It's a very good point about the Bhp and torque scales by the way.....something I'll know to look out for in the future.

 

[Spike]

I'm not sure on the specifics of the Dyno Spike, that's starting to go over my head........
Figures were at the wheels, so approx 186 for a Mk1 as opposed to your 207 for a Mk2.
(for the layman) Figures quoted in print were those derived from calculations as discussed earlier in the thread, the headline 232.1 was on gas at the wheels......
Motor was standard at that time except for pipercross and quicksilver backbox.

It's a very good point about the Bhp and torque scales by the way.....something I'll know to look out for in the future.

yes, as for the scaling its just a way of making things difficult rather than easy, as for your power figures, these really do substansiate my 207, as 186 is a good start for a std mk1. if you look at the torque figure thats not far behind at the same rpm, i figure the extra comes from the shorter manifold pushing the torque in the upper rpm, something you would expect, however this will be at a loss from the bottom end, as also is usual.
i wonder how the backbox affected the torque figure, how did it feel?

 

[ed_harland]

oh some sense at last - refreshing chaps.

:approve:

 

[Ali]

Never had an "ATW" run done. Mine rap 255 and 253 on different rollers. Pretty good going!

The figs you have there are "calculated" from the figure At The Wheels.

Yeh. seems fairly accurate tho!...He says.

 

[renaultalpine]

Some of the results (flywheel) for the mostly standard cars we ran with the racelogic gear.

Ph1 230.2
Ph1 227.5
Ph1 210.1
Ph2 239.7

Transmission losses were all less than 20%.

We ran Captains Ph2 as well but have mislaid the figures. He may still have them.

 

[Spike]

Some of the results (flywheel) for the mostly standard cars we ran with the racelogic gear.

Ph1 230.2
Ph1 227.5
Ph1 210.1
Ph2 239.7

Transmission losses were all less than 20%.

We ran Captains Ph2 as well but have mislaid the figures. He may still have them.

again, how were the flywheel figures calculated? or were these on an engine dyno?

 

[ray]

race logic is a gps in car logger ph2 239bhp hmm fly wheel hmm i think those figs are a little misleading

 

[ray]

let me spell this out for you all A COUPLE OF CONTROL CARS AND THE MODIFIED CARS ROLLING ROAD SHOOT OUT ONLY WAY TO COMPARE

 

[TRW1]

i wonder how the backbox affected the torque figure, how did it feel?

So long ago now it's hard to recall......probably such a subtle difference you wouldn't really notice though I think the great sound of a new filter and exhaust convinces us all the car must be quicker........even if sometimes the opposite is true.
Back then I was probably happier going slower but sounding better.

 

[phillv6]

let me spell this out for you all A COUPLE OF CONTROL CARS AND THE MODIFIED CARS ROLLING ROAD SHOOT OUT ONLY WAY TO COMPARE

Couldn't agree more Ray [cmilie=iconcheers.gif] also as another note no-one has mentioned the effect ambient temperature and air pressure has on the way an engine runs, therefore comparisons are only really valid taken on the same rolling road on the same day I'd say.

Phill

 

[ray]

correct thats why we need a control car once that has been run it dosen t matter as it will be the percent between that and the other cars that will be measured i always find this odd a tuner can tell you to a thousand of an inch mills what ever the clearance in your engine but when it comes to how much power etc you have it all gets a bit of a guess hows that work then?

 

[TRW1]

I believe climatic conditions can be input into the dyno operators calculations to give a supposed level playing field figure but obviously it's just another variable open to their "interpretation" and more margin for error.
As Ray says, same dyno same day is best.

 

[Spike]

i wonder how the backbox affected the torque figure, how did it feel?

So long ago now it's hard to recall......probably such a subtle difference you wouldn't really notice though I think the great sound of a new filter and exhaust convinces us all the car must be quicker........even if sometimes the opposite is true.
Back then I was probably happier going slower but sounding better.

It's no good having nice wheels if you are going too fast for everyone to see them!

 

[TRW1]

It's no good having nice wheels if you are going too fast for everyone to see them!

Amen

 

[Spike]

LOW BALL HERE:
the only problem with the dyno shoot out that ray has suggested has already been mentioned a couple of posts ago, ambient temp and pressure. might sound picky but have had problems with readings on the same bike after its gone from a stormy to sunny day, both pressure and temp changes, so you do your mods and find there is less power!!!!!!!! :evil: also dynos allways read best first thing when the cell is cold and the air is crisp.
i dont want to be the last man in, thats all! [smilie=icon_eek.gif]

 

[TRW1]

No problem......we book the dyno for 02:00 in the morning...I'm first, Spike can go second and so on, all done by 06:00 and back to sleep.

 

[Spike]

No problem......we book the dyno for 02:00 in the morning...I'm first, Spike can go second and so on, all done by 06:00 and back to sleep.

me first, baseline 207!!! [smilie=icon_eek.gif]