[Sweet]

Have I missed it or did you not try a tuning box prior to the remap?

[Shaunee]

Have I missed it or did you not try a tuning box prior to the remap?

That was the original plan, but on the day I decided to get stuck into a proper Stage 1 ECU tune.


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[terminator x]

So did anyone say anything about a gearbox "map" now that you're running more power?

 

TX.

[Sweet]

That was the original plan, but on the day I decided to get stuck into a proper Stage 1 ECU tune.
Sent from my iPhone using Tapatalk

That's a shame, I was looking forward to the graphs as I'm thinking of going this way myself.

[Shaunee]

So did anyone say anything about a gearbox "map" now that you're running more power?

 

TX.

 

Did discuss it but only in passing really.

 

I'll look into this in the near future, but the gearbox OEM mapping seems fine at the moment.

[Shaunee]

That's a shame, I was looking forward to the graphs as I'm thinking of going this way myself.

 

Yeah sorry.... it was just going to push out the timeframes.  Obviously there would be the additional cost to me as well.  I just wanted to crack on as I have so much more I want to get done and I'm trying to get it all done by the end of this year.... which will soon fly by. 

[TD757]

i'm keen to know how you actually change the values through the OBD port, software you use, which values to change etc.

Will there be more on this aspect when you get time?

Is it possible to have a copy of your latest map?

[Shaunee]

TD757,

I didn't physically change anything myself in the code.... that's what the guy with bigger frontal lobe sitting next to me did.

 

You'd need to speak to Litchfields about getting access to this map file.

[Shaunee]

Performance Testing - Stock vs Stage 1

It’s alright having dyno graphs but this is all about (in my opinion) how any power relates to performance on the black stuff.

 

I don’t tend to drive my car on the dyno to work and back, so it’s always good to use other forms of reference to measure changes.

 

Something I will do throughout this project is give you the good, the bad and the ugly.  This is all about a journey and things won’t always go to plan etc…. That’s life especially with car tuning.  Hopefully negative things will be infrequent though.

 

So what are we going to use to benchmark performance at this level of tuning…. Acceleration runs, specifically down the quarter of a mile.

 

I’ve already mentioned about using a VBOX to measure acceleration, so that will certainly be used and I’ve also ran the car down Santa Pod dragstrip when it was stock.  So we’ll use that as another means to judge performance.

 

VBOX Data

Some of you may take the data I will provide in this update and immediately compare it against other data available on the net.  Whilst it is fine to do that, you do need to be very careful that you’re comparing apples with apples.

 

The fact is that you can get VBOX data from any location you choose.  Some of those locations maybe uphill or downhill.  Some of the data captured may actually be corrupt.  When you use a VBOX and look at the screen for the results gained, that won’t tell you ANYTHING about the integrity of the data and run.  I know it’s 100% possible to log a run on a VBOX that is both downhill and has dropped satellite connection part way through the run….. Both of these elements can GREATLY influence the figures given by just using the onboard screen of the VBOX.

 

How do you verify that the data and run is pucka?

 

You must ensure a memory card is in the VBOX to store the logs and check the data validity on both the desktop software that comes with the VBOX and using an online tool called “VBOX Verify”.

 

VBOX Verify will do just that….. It will check the data file is clean and that the run is performed within an accepted “slope” tolerance. What the later means is that it will measure the slope of the road (height data is captured all the way through the run), by ensuring that it remains within a certain % allowed throughout the run.

 

However…. There’s even more to it than this.

 

Whilst there is a slope check you can still gain acceleration performance by running on a road ,that whilst still falls within the acceptable slope (downhill for instance), does give the run an advantage.  That’s physics!  When you’re looking to compare figures that are coming down to 10ths of a second difference…. It can all help to make that difference.

 

The other area is road surface.  Due to the makeup of the asphalt on normal roads you will almost certainly have less tyre drag on a public road, then you will on a proper (not airfield!) drag strip.  Drag strip tarmac is a much denser compound than road tarmac and doesn’t absorb water like road tarmac does.  This is why when it rains it takes them so long to dry the drag strip track out.  What this ultimately means is that there is more tyre drag on the drag strip (along with the glue prep they spray on the strip to aid traction).  This will normally cause slower acceleration figures on drag strips and reduced terminal speeds.

 

This sounds all really anal…. But again, when you’re comparing down to 10ths of a second, it can make an impact.

 

Context and accuracy is king in my opinion and you need to be as like for like as possible.  So be very careful when you compare data you’ve attained against others.

 

Dragstrip accuracy - surely that’s a give then?

If it’s a proper dragstrip then at least you be assured that the timing slip will be accurate, however, there is more to it than this.

 

Just because you run on a dragstrip it doesn’t mean your performance data (time and terminal speeds) will not vary between different dragstrips.  You also can’t guarantee that each time you run, your car will absolutely run the same times.  

 

Assuming your car is healthy, so much can influence a drag run when you’re hunting those small 10ths of a second.

 

Preparation of the track can make a difference (grip and drag).  Weather conditions can make a difference.

 

In my opinion the environment and weather can have the biggest impact when comparing data.  Some cars may be impacted more than others.

 

Just don’t take everything literally.  It’s not that black and white.

 

Vehicle Weight

Vehicle weight can also influence acceleration times, as the power to weight maybe different.  If your car is fully loaded with the “fat” options, there is every chance that a lighter specced car will perform better.  Based on the options available I think the difference in times will be small, but every little counts when you’re getting the magnifying glass out on performance figures.

 

Again….. Something else to be aware of.

 

Mine is a full fat version, but I do need to get in on the scales to find out exactly what that means.

 

Conditions on the day

The ambients were good being in mid teens.  The cooler the air the better it should be for turbocharged cars.

 

Track preparation wasn’t the best.  Due to rain the previous day and earlier that morning, together with the cooler air, grip for me was an issue.  Something I never experienced a few months ago…. However, I’ve also got more grunt now, so that certainly wouldn’t help with the standing starts.  It is what it is though.

 

There was also quite a strong crosswind.  Again that isn’t going to help matters.  Although it’s better than a direct headwind!

 

There were LOADS of cars running.  So much that we were queuing out the end of the fire up lane.  It was a good 30mins between runs.  This means that whatever heat you’ve built up in your tyres will dissipate by the time you get to the start line (less grip), and you also have the added awesome feature of heat soak due to queuing! The OEM intercooler is starting to struggle with a remap on the RS3, so any additional heat build up isn’t going to help matters.

 

You can only run in the conditions that are apparent on the day though.  Such is life.

 

First run 12.14 @ 114.33mph

I wasn’t expecting today to go well if I’m being honest, as the conditions weren’t the best.  This first run gave an indication to how the day was possibly going to pan out.

 

Grip wasn’t good.  Wheelspin at the start together with axle tramping.  That isn’t good.  More grunt and not enough grip on a standing start.

 

I also noticed the gearbox appeared to stutter from 1st to 2nd and 2nd to 3rd.  3rd to 4th was fine.

 

Second run 12.08 @ 114.63mph

Still had traction problems and gearbox stutters, but at least the time was coming down.

 

Third run 11.98 @ 113.63mph

This run had a better launch, but still span the fronts wheels up.  No axle tramp and the stutters weren’t appearing on the gear changes.  The track felt like it was starting to improve (this was just after 2pm).

 

 

Positives

I’d be lying if I stated I wasn’t hoping for more, however, that was in relation to the ET’s and I was hoping for an 11.8x.  We’re talking about a 10th of a second here and considering the grip issues I had experienced, the 11.9x achieved is a solid measure.

 

My car clearly has more grunt now than it did before when stock. If we look at my best from the previous stock figures at Santa Pod, to these runs, the differences are marked in both ET’s and terminal speeds:

 

Stock

12.34 @ 111.25mph; 60ft in 1.83s; 330ft in 5.13; ⅛ in 7.92 @ 88.75

 

Stage 1

11.98 @ 113.63mph; 60ft in 1.84s; 330ft in 5.02; ⅛ in 7.69 @ 92.89

 

Taking into account my other two runs from yesterday were seeing terminals @ 114mph, this backs up the dyno after figures with the increased BHP at the top end.  The car is quicker down the strip because of this.

 

At the level of Stage 1 on these cars you’re not going to see massive decreases in times, as the top end BHP isn’t being lifted that much over the stock figures.

 

Also the extra torque this Stage 1 now has won’t be benefiting the drag runs as much as they benefit the car on the road in normal driving conditions.  The mid range will only be utilised through the first gear, where this can impact grip anyway.  There is also less load in 1st so the benefit of the mid range is limited.  Drag runs are really about the upper rev band.

 

Negatives

The biggest negative is overall grip on launching.  This is probably a combination of the track conditions and my hefty torque in the midrange on that 1st gear pull from a standing start with launch control.

 

I’m also on the thinner 235 section tyres at the front.  Most owners will have the 255’s on the front.  This should theoretically aid traction from a launch.

 

Whilst run stability improved on the third run, I never saw a 60ft in the 1.7’s, which is absolutely possible with these RS3’s.  Assuming the rest of the run is clean, it is absolutely possible that every 10th you decrease your 60ft time by, you can double the reduction at the ET. When my car was stock I saw a 1.75s 60ft…. And I’m not the only one.

 

We’re getting quite anal here and this car is not being modified to be a drag monster…. It’s a road car and is setup as such.

 

What’s next?

The next dragstrip event is at Shakespeare Raceway this coming weekend.  I’m going to try and attend and see if I can get the car in 11.8’s.  I’m not going to change anything on the car, but may play with tyre pressures to see if I can stabilize the grip more on launching.  Lower pressures normally aid grip, but that will increase the drag and decrease my speed….. So it’s a balancing act.

 

Apart from this it’s on to Stage 2.  Intercooler and remap again! Then hopefully back down to strip to see if this helps my overall performance figures.

 

Talking of performance figures

What about my VBOX data from these runs!..........

 

Here is the verified VBOX data from the above quickest drag run at Santa Pod.  Remember this is from a drag strip run…… not a road log:
 

0-60mph in 3.50s

 

60-100mph in 5.31s

[/URL]

 

0-100mph in 8.81s

 

If you wondered how accurate these VBOX’s are…. Look at this VBOX log taken on my quickest run.  Pretty close to the official strip timing for a box that costs a few hundred pounds!

 

 

Here’s the quickest run on video:

Edited by Shaunee, 18 September 2016 - 01:53 PM.

[terminator x]

Anything that can get to 100mph in well under 10s is properly mental!

TX.

Sent from my STV100-4 using Tapatalk

[Eigdoog]

Very good write up Shaun. You are right about the grip as i got a 1.7 in the 60ft. Not as low as 1.75 but still helped me get my car in the 12.1's. 

[Alex]

Amazing write up Shaun's, this is a real credit to you.

[RS3Pilot]

It would be interesting to see if shifting gears earlier would benefit 1/4 times, the extra torque from the map drops away after 5k rpm and the shift points are well above 6000... Acceleration is about torque between tyre and road, which includes engine and gearing and often means holding a gear longer because of the higher 'tarmac' torque, but in the mapped cars with higher low engine rpm torque it could be beneficial keeping the engine there by shifting earlier?

[Shaunee]

Thanks again guys for your positive comments!

 

Only two weeks to go until I start progressing with Stage 2! Stage 3 is also being planned to follow on shortly afterwards.

 

RS3Pilot,

I've tried this before but admittedly not on the RS3, and the car was slower down the strip.  I'll have a play if I can and report back on any benefits. 

[RS3Pilot]

probably best trying the short shifting with your vbox on a bit of deserted road just to see if the principle works rather than experimenting on the drag strip, what hardware are you doing at st2 and 3? Great project by the way, I've never seen anything like this detail of explanation and the rigour in executing the test runs is exactly what you need if you're going to determine the individual gains of each modification, thanks for posting!

[Shaunee]

RS3Pilot,

Stage 2 will be intercooler and remap

Stage 3 turbo time

Stage 4 we'll have to wait and see (although I do have a goal, but I'll talk about that in the future)

 

I went back to the drag strip today...... update will be inbound tomorrow.

[Shaunee]

Performance Testing Stage 1 - Round 2

I did say on the last update that I would be attending the next dragstrip event at Shakespeare Raceway… so here we are!

 

I was adamant that the conditions at Santa Pod last weekend were not the best, and for me, caused issues due to poor grip levels.  Like we all say though…. The bullshit stops when the flag drops, so I was eager to try again under better track conditions.

 

Conditions on the day

The ambients were warmer today than last weekend high teens starting off, which quickly moved to low 20’s.

 

Track preparation should be better as the weather leading up to today wasn’t that bad.  It was at least dry the day before and no rain had fallen overnight.

 

As soon as I got to the track they were already out prepping it which is always a good sign!

 

Another good thing (from a run / heat management perspective) is that there were no where near as many runners here today as Santa Pod the week before.  Which should mean I can better manage my runs, rather than being dictated by the traffic.

 

 

First run 11.99 @ 114.64 60ft 1.87s

 

I’m going to start and quote the 60ft in the title.  This is very important to me now as you’ll see further on.

 

Balls….. It’s lighting up the front tyres again and still axle tramping.  Car feels really light going up the rest of the track as well.

 

This is the first run though and I was first on track….. I’m hoping things will improve as the track gets more rubber and heat into it.

 

I’m going to get straight back on, back to back!

 

Second run 12.06 @ 114.82 60ft 1.94s

 

Holy moley…. What happened on that run.  Look at that 60ft!

 

Front grip was atrocious! Still feels like it’s struggling for grip over the rest of the track as well.  It’s 4WD…. What’s going on! lol

 

One more run, but something to try first to improve grip….

 

Tyre Pressures

I’m adamant this is all about grip and not because my tune hasn’t got the power.

 

I normally, as a matter of course, pull tyre pressure down on the fronts for drag runs on a Haldex type setup and all round if it’s permanent 4WD.  This is assuming I’m having grip problems and I want to try and help with this.

 

The downside to pulling out tyre pressure is that this normally negatively affects the speeds you attain.  This is due to increased tyre drag, with more of the tyre (as it’s effectively flatter) spread on the tarmac.

 

In my opinion if you’re not having grip issues don’t mess with your tyre pressures.  One of the guys running his stock RS3 at the pod last weekend did this.  He wasn’t having grip issues, but with him pulling his tyre pressures down it reduced his terminal speeds by a couple of MPH.  His ET’s were not really affected, but this is what it normally does.

 

Checking my pressures I was still running stock levels for 235’s on the front, which was 39psi.  I pulled these down to 32psi at the front and left the rears stock.  It’s the fronts that are having to cope with all the work in reality.

 

Third run 11.98 @ 114.86 60ft 1.85s

 

This is just as bad as Santa Pod…. I just don’t think I’m going to get anywhere today.

 

At this point I decided to rest the car up and take stock (and cry!).

 

After just over 30 mins I headed out for the next run.

 

Fourth run 11.97 @ 116.17 60ft 1.93

 

The track had been running for just over an hour by now and it’s amazing how quickly a track can evolve as more cars run, increasing track temp and rubber laid down to increase overall grip.

 

OK, the ET and 60ft were still crap but look how the terminals have picked up.  The car felt much better after launching then the previous runs.  The strip on the whole was starting to feel quicker and the car was more stable after launching…. That increase in terminals backs that up.

 

If the car was now achieving that ET with that 60ft and terminal speed, things were looking a lot more positive now. I’ve just got to try and get a better launch in.

 

Something I noticed was that the inlet temps were very high after each run, so I decided to take the approach of letting the car cool between each run for at least 20mins.  In my opinion this isn’t the best thing, as you tend to lose heat from your tyres (grip) and from your downpipe and turbo exhaust housing.  It’s really good to ensure your exhaust housing and downpipe are red hot to ensure gas speed (power output) is optimum. Fine line here though as you don’t want heat soak.

I can’t wait to get this intercooler swapped out!

Edited by Shaunee, 25 September 2016 - 12:48 PM.

[Shaunee]

Fifth run 11.87 @ 116.03 60ft 1.87

 

We’re in the 11.8’s!!!!  Still maintaining terminals but still struggling off the line.

 

At this stage I also took another 2psi out of the fronts.  We’re now down to 30psi at the fronts, whilst the rears are still stock pressures.

 

Sixth run 11.80 @ 116.10 60ft 1.80

 

Boom!!  11.80 dead!!

 

To be precise it was 11.80045.  That’s 4/10,000ths of a second away from an 11.7!!! That is crazily close.

 

Much better 60ft this time, but I know there is more left in the car on launching.  The rest of the run felt proper solid.

 

It’s worth pointing out that even with this time the fronts are still spinning up on launch and the front is axle tramping.  It’s mental!

 

I got greedy here and did a back to back run straight after.

 

Seventh run 11.86 @ 115.36 60ft 1.78

 

Triple balls!!!!

 

I finally bust into the 1.7’s 60ft, but got a worse ET and trap speed.  That’s exactly what happens when you get heat soak - you lose power!!!! Surely had that launch been without heat soak, I think I’d be staring at an 11.7x timing slip now! Damn…… but as I like to say, it does it when it does it.

 

Time for a rest (for the car and me!) looking to running again after lunch.

 

Eighth run 12.05 @ 115.30 60ft 1.95

 

This run was some 1.5hrs since the last run, and look at how quickly the track can change again!

 

These were the worst grip levels I had experienced all day up the strip.  I’m not over exaggerating here, but the tyres were squealing all the way through 1st, 2nd and 3rd. That’s crazy.

 

Look at that 60ft! Ha

 

Ninth run 12.03 @ 115.28 60ft 1.91

 

The track had clearly taken a turn for the worse during the afternoon.

 

That’s it…. I’m done for today!

 

Positives

It’s amazing how better track conditions can change the times.  OK it’s not when you think about it, but there has been a marked improvement seen even at the same level of tune.  A point probably worth underlining here, this car has not seen any further changes since the last runs at Santa Pod.  It’s in the same state of tune.

 

To put down an 11.80s quarter is brilliant.  Based on what I know this is the quickest official drag strip time for a Stage 1 RS3 on stock tyres, full fat weight and pump fuel in the UK.  Also I managed to do 3 x 11.8x passes on the same day.

 

Based on the testing done today I’m as confident as I can be that the car, even at this level of tune, has an 11.7x drag strip pass in it.

 

The other element I’m really happy with is the trap speeds.  Hitting 116+ at the quarter, especially with 10psi taken out of the front tyres, is impressive.  It backs up the BHP claims from my dyno plots in my opinion.

 

The torque increases seen on my dyno plot (+100ftlb over the stock run on my car) is real in my opinion, which is why the stock launch control strategy is causing me ultimate grip issues on launch.  Too much sauce on launch.

 

Let’s see where we are now versus the stock drag runs I did:

 

Stock

12.34 @ 111.25mph; 60ft in 1.83s; 330ft in 5.13; ⅛ in 7.92 @ 88.75

 

Stage 1

11.80 @ 116.10mph; 60ft in 1.80s; 330ft in 4.93; ⅛ in 7.57 @ 92.74

 

Negatives

It’s easy to get side tracked by focussing on these performance times, but this car is for the road and that is what’s most important to me.  I don’t launch the car on the road, I drive it through the gears.  The drag figures do not highlight how quick and driveable this car is on the road.

 

Grip is ultimately my current enemy on the strip at the moment.  There are a number of options I will investigate, focussed on what changes can be made to the launch strategy (reducing boost).

 

I could also look at increasing mechanical grip….. Fitting different tyres and/or the wider 255’s on the front.  To be honest I would rather not put 255’s on the front.

 

One thing I will look at is geometry.  Stock factory geometry is normally quite loose, so I’ll get the car on the alignment rig and tighten that up if needed.

 

The last but probably the easiest, is to start running the car at Santa Pods Peak Performance days.  This is when they heavily prep the track, and continue to keep that up through the day.  This ensures the strip is at it’s most grippiest.  The downside is that these days are £60, as opposed to the normal £25.  But since this doesn’t mean I need to change anything else, and it’s only affecting the drag strip outcome (potentially), it does kind of make sense to at least try this route.

I’m not going to bother messing around with anything for the next few weeks, it’s Stage 2 testing after all during early October.

Edited by Shaunee, 25 September 2016 - 12:49 PM.

[Shaunee]

VBOX Data

I can’t stress this enough…. These are figures from the drag strip run, not for road runs.

 

As per the drag times, the other areas of acceleration also saw a marked improvement from the Santa Pod runs.  Better track conditions / grip is good thing!

 

These are taken from the quickest quarter run logs:

 

0-60mph in 3.40s

 

60-100mph in 5.08s

 

0-100mph in 8.49s

 

Looking back at what was achieved at Santa Pod, these figures have been improved upon as follows:

 

0-60 0.1s quicker

60-100 0.23s quicker

0-100 0 0.32s quicker

 

Personally, I would expect the measures / results to be even quicker on the public highway.

 

The data logged via VBOX is very informative, way beyond just giving performance figures.  One thing you can look at is the amount of g’s the car is pulling, which can allude to drop off’s in power / traction.

 

I’m noticing that the 1st to 2nd gear change is quite harsh and the box appears to stutter when doing a fully loaded launch run.  Together with the wheelspin and axle tramping I get, this can be seen on the g’s plotted.

 

Let’s look at the VBOX quarter mile log associated to the quickest drag run achieved:

 

 

I’ve highlighted five areas from left to right on the g plot.

 

The 1st from the left is showing lack of traction initially, which will be a combination of wheelspin and the front axle tramping.  It doesn’t gain full traction until around 16mph.

 

The 2nd from the left is showing the fairly substantial 1st to 2nd gearbox shift stutter.  I’ve seen this on stock car logs, but I think this is being amplified by the Stage 1 remap.

 

A DSG remap may help certainly for the 2nd issue.

Whilst not affecting the run in reality the 3rd, 4th and 5th areas have been highlighted as these show the 2nd to 3rd, 3rd to 4th and finally 4th to 5th gear changes.

Edited by Shaunee, 25 September 2016 - 12:51 PM.

[Fivepotfan]

Great thread Shaun, never seen this level of information being shared before (and at bugger all cost to the rest of us too!)

 

I will be following the next stage of the build with great interest, I am really looking forward to seeing the numbers and stats with the uprated intercooler fitted.

 

Roll on October!