First the good news....

Flea has found much of my lost BHP (it only gave 270bhp at the Dyno Demon RR day earlier this month). Flea took the car on Wednesday and had two tasks - sort the awful misfire as the turbo spooled up and try and stop the ECU learning so quickly

He's done lots to the car, including removing a HUGE section of map where it was running massively rich (presumably to support running at over 2 bar). Its now smoother and much nicer to drive - also feels a fair bit quicker than it has done recently.

From what Fleas has said, the ECU learning should have been greatly reduced - I've turned my ECU reset device off, so I'll be running for the next few days without resetting (including a trip to Newcastle on Wednesday, so that will give it plenty of chance to try and learn)

We finished off today with a quick dyno run at PowerStation, which confirmed the recovery of well over 70bhp and a much better delivery.

the bad news is that its still not right, but its NOT down to the mapping in any way (PowerStation were very pleased about how it ran)

However, its STILL has the misfire (but now only at 1.75 bar) and peak power is a rather measly 350-ish bhp.

Talking to the guys at PowerStation, we're now thinking there may be a restriction in the exhaust somewhere, as the power is tailing off at the top end (it used to carry on climbing until it hit the limiter). We're suspecting a collapsed baffle or maybe even a dented pipe. I'll have to get it all off to check it out.

So - a BIG thanks for the time and effort Flea has put in - I can already tell its made a difference, but the commute to work tomorrow will confirm this. Its MUCH harder to sort a car like mine, Flea would be able to produce worthwhile gains from less-modded cars with ease.

Why are you mapping it again what was wrong with your finished PT map that you ran at TOTB?

Hi Nigel,

About the misfire, I had it also above 1.7 bar, but with the OE injectors and some 4 bar fuel base pressure. After I installed the bigger 465 cc injectors, I could go up to 1.86 bar of boost without any misfire. Higher I didn't dare to go, because of the std internals. (Forged internals waiting for the installation next winter)

Anyway in my case the misfire was purely lack of fuel.

- Jari -

J - I had a big misfire at max boost - probably the spark being blown out, but possibly caused by WAY too much fuel (AFR was below 9:1 )

The PT map seemed to be perfect at TOTB, but the car has got progressively less powerful in the four months since then. This is why I'm going to look for an exhaust restriction - a collapsed baffle or dented pipe could cause the problem I'm having (with the misfire caused by excessive backpressure, resulting in big EGTs)

Jari - I've wondered whether it is my injectors - they are 16VT injectors, rated at 5 bar max. By the time I'm at 1.7 bar, with a 3.8bar FPR, I'm well over the pressure rating.

However, we're pretty sure the injectors are coping, as there was too much fuel, rather than not enough.

I'm going to gap the plugs back down again, although I'm going to do it in very small steps - last time I went straight from 0.8mm to 0.6mm - it cured the misfire, but lost me power.

Well I’ll add a little bit more to what Nigel has already mentioned. The task as stated was two fold 1. eliminate the ecu adaption, or at the very least make it better 2. Map the car correctly at WOT. Well the latter was going to be fairly easy however the former was a little more tricky. That said, I am very confident that the ecu adaption has been curtailed considerably although it will take Nigel a fair few hundred miles to confirm whether it is a 100% cure.

So a bit of background. Ever since Nigel upgraded to the 16vt injectors (384cc) he has experienced problems with the ecu leaning out the fueling over time. However, recently he has added a 3.8 fpr to get a little more flow out of the injectors. Nigel said this had the effect of increasing the speed at which the ecu adapted, with the fueling leaning out from a freshly reset ecu over the course of 50 miles. As a result Nigel added a timed circuit breaker so that he could reset the ecu when the car was parked for over an hour.

Well a recent visit to the Dyno Demon rolling road day proved very disappointing with the car making 270bhp, however it was the fueling that was most worrying. The first run saw fueling between 12 and 13.1 afr when on boost which is dangerously lean. The second run after a reset ecu saw the fueling drop to 11.1 – 9.8 and then 10.8 at redline.

I started last Thursday with the first task to asses how quickly the car was adapting…

Reset Ecu – PT map

Run 1 – 15 miles covered

Run 2 – 32 miles covered


Wow, within the space of just 17 miles the ecu had leaned the fueling considerably, it was even more extreme than Nigel thought. As you can see, with a freshly reset ecu the fueling was dropping into the low 10s at 3100rpm and not climbing back into the 11s until 6100rpm. It was actually hitting 9.9 afr in 4th gear hence why Nigel had misfires at this level. After a further 17 miles the fueling curve (same shape) has now shifted upwards with it staying in the 11s until 5200rpm where it climbs sharply into the 12s and then almost touching 13 afr at 5600rpm at which point I backed off to save doing any damage. That is some extreme adaption!

There were a couple of other problems i.e. the cold start was too rich and would struggle to catch (9.8afr will do that), and low down off boost WOT was also too rich at 11-12 afr, it should be close to stoich. Anyway, by the end of Thursday I had fixed these issues and felt confident that I had also corrected the ecu adaption. The only task now was to put some miles on it to see what would happen. It needed a couple of little tweaks having done 140 miles by Saturday, however by Monday afternoon I had covered a further 200 miles (340 in total) before going on the dyno, this is without resetting the ecu. At this point the fueling remains unchanged with a flat 11.3-11.5 all the way to redline.

Reset Ecu + 200miles – Remap

Final Run


Now I’ll hedge my bets for the minute but as things stand it’s looking pretty darn good. Going from 17 miles extreme adaption to 200 miles without is a good start. Nigel is going to run with it and see if stays just so. It was mapped for 1.6-1.65bar and there are zero misfires.

The dyno run at Powerstation confirmed that the fueling was perfect throughout. The only disappointment was that while gaining 70bhp+ from Dyno Demon a week ago, it is still down on power at the top end with 352bhp & 330lbs/ft. This is simply due to the torque dropping off a little too quickly despite the boost holding well. It still feels immensely fast although opening up the exhaust side could release those lost ponies. I should note that the engine is still very strong with a compression test giving 152 – 160 on all five pots.

All in all I’m pleased with the way it went. It was quite a bit different to mapping my car, in some ways harder, but hopefully the result will show itself now and in the long term. A few thoughts about Nigel’s car as a whole, well it handles very well indeed, I have been making notes For a big power car it is very smooth to drive on wide open throttle, part throttle (green dump valve spring!) and also pootling around town. I have driven a lot of fast cars from Evos, Porsches, BMWs etc and this was an extremely good all round package especially considering the miles it covers annually.

Looking good Flea and Nigel

Are you planning on removing the exhaust Nigel?

Good results there guys!

Any chance of getting the dyno results up so we can see what the torque curve is trailing off like?

Nigel,

I'm using the Audi RS2 plugs with 0.6 mm gap since three years and I haven't notice any power lost.

My OE injectors were cleaned and measured. They were good up to 6.5 bar by long opening times, which is happening more or less in high revs.

Now with the 465 cc injectors I can adjust the amount of fuel according to the boost (ECU adaption can't reach that far ) by adjusting the base fuel pressure. I can use boost level of +1.7 bar and I can see quite black smoke behind the car even upon 6000 rpm.

About AFR and EGT, does anyone has any comparasion to them, because I feel that my car has best power, when the EGT shows +900 degC, under that it feels powerless. So what equate the temperature of, lets say, 920 degC?
I have AEM UEGO wide band lambda, but not yet installed.

-Jari-

Thanks for the update Leighton. As I said to you last night, for my car to be praised by you is very satisfying. Clearly, you've driven lots of fast cars and your own Coupe is hardly a slouch I've spent a long time (but not THAT much money) getting the ride, steering and brakes to the point where it can cruise happily on the motorway without exhausting the driver, or hack around a track with precision and confidence

I'll be getting Paul at Motormech to have the exhaust off to inspect it for obstruction - the way it holds back at the top end would suggest something is strangling it. PowerStation reckoned the jet-like noise it was making is indicative of an exhaust-side restriction

I think its *finally* time to go for a 3" straight-through system, with a couple of decent-sized silencers to allow me the luxury of a relatively quiet cruise.

Any suggestions anyone?

Adding / removing silencers doesnt seem to make any difference to mine, Cat on = quiet, cat off = loud! and that's it.

Maybe go for a race cat?

suggestions for Nigel's new exhaust (Santa permitting)

Stealth Systems in Southampton did my 3" and is slient, that is 3" downpipe, std CAT converter to 3" flanges, and one large back box

looking good nigel,wish my afr graph looked like yours !

looks spot on !

Do you use a catalysator?

no - decatted

PowerStation dyno graph

as you can see, the torque tails off quite a lot - on previous runs, my power has been increasing quite hard all the way to the limiter

2 bar PT plot torque tails off quite dramatically as a consequence of the flat power curve (over 390bhp for almost 3000rpm)

PT power plot @ 1.6 bar (actually the shape really doesn't look that different to yesterday's PowerStation graph

PT torque plot @ 1.6 bar

checked a couple of things on the car tonight

the baffle in the SuperSprint back box is perfectly intact (in fact its in remarkably good condition, considering its done at least 120,000 miles). I've also checked all the way along the exhaust - no dents or dings

I also had a quick look at the boost pipes - very oily (in fact I have oil leaking out of some of the joints between the hard pipes and the silicon pipes).

If I have oil leaking, then surely I could have a boost leak or three as well?

Time to get the bumper off and have a closer look, I think

Is it worth de-gunking the inside of your intercooler too if you have done lots of miles on it?

quite likely - I'll check it out (how on earth would I clean it out though???)

I only have problems with misfires at 1.7Bar+ at about 4800rpm+ but it's phat as I get a good 4 foot flame out the back (got some cool vids), plus sometimes a load of black smoke. When I turn the boost down to 1.6 it's perfect all the way to 7250rpm. Even though we have very close specs I think are maps are completely different as I have done a few dyno runs at my uni and the fuelling has been spot on, WOT and transition maps (we got a cool afr logger). With my latest re-map I haven't noticed any drifting in afr from the adaption. Last time I had it drift after about a week but now it seems spot on for 3 weeks. I've order the stuff the re-wire my coils hope this solves the missing as I miss my 400ft/lb too

Pour petrol in it and let it dissolve the gunk.

Hi Nigel,

I bet you have a boost leak some where. Your torque curve gives that indication.
I did have boost leak in my last 410 bhp RR run and the torque curve was like yours. It was the hose just before intake manifold, there were 3 cm long cut.

PM me your email address and I will post you my RR print with the boost leak and also picture of the broken hose.

- Jari -

Is that a typo there Nigel, as that is your torque taking a massive nose dive and your bhp staying at over 390bhp for 3000-ish revs.

possibly - I glanced at the graph and assumed it was torque that stayed flat while power reduced. Now you've mentioned it, its obvious that its the other way round - now corrected

No wonder it felt quick - almost 400 bhp before AND after a gearchange

Nigel - you know my thoughts on this.

Here's some graphs for my car with 3inch exhaust a five stud adaptor:

http://i11.photobucket.com/albums/a198/suba11/perfectmap2.jpg

http://i11.photobucket.com/albums/a198/suba11/perfectmap1.jpg

With no other changes but with a V-band adaptor and the the same exhaust that you run:

http://i11.photobucket.com/albums/a198/suba11/coopbhpcomparison.jpg

http://i11.photobucket.com/albums/a198/suba11/cooptorquecomparison.jpg

The car was mapped differently, and on a difference RR but....you can see the torque shift up the rev range.

Remember that I am also running a much smaller turbo than you, so you may well notice a fair bit more of a gain.

I dont think that a dented exhaust would loose you that much power (unless it was very bad). I'm more inclined to say that it's a boost leak or IC restriction.

Stealth Systems are no longer in existence

Not suprised really, they didnt have any insurance and spent a couple of months fobbing me off when they smashed my rear windscreen.

I would bet money the guy that did all the work is around under a different company. His skills are fantastic, just a shame about the shady side.

Am struggling to find someone to drill a lambda boss into my decat for a wideband sensor. Regal will do it but I don't like them

Some more good news

Since Flea mapped the car, I've done the following miles

90 miles home from PowerStation
80 miles to work and back
395 miles to Newcastle and back

all without resetting the ECU

Just to check the ECU learning, I floored it and saw 8 LEDs on my narrowband AFR meter, which equates exactly to what leighton was seeing as he was mapping it at around 11AFR

So - fingers crossed, it looks like Leighton may well have sorted the problem

I'll know for certain in a few more days, but its looking pretty good (especially seeing as it would drift to over 13AFR after 80 miles on the previous map)

Good news Nigel, think this has made my mind up for where to go to get my car mapped