Prawn and BigAls A3 Track Car

jardo drove it up to me in feb, and on the way up t started peaking 22 again, then the next day, back to 17!

Thats because it loves me, it can feel the call of its real master...

And because I was driving it properly, it loves a bit of boost! When I come home for the bank holiday I'll take it for a spin and see if I can make it pull some man figures?

I've got a video of it pulling 22 a couple of times on my phone actually, it goes nicely at 22PSI :)
 
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Lol no worries. I put it there to try and drum up some interest.

Have you got any plans for a fmic? I should have mine on before the ring.

Also have you got the federals fitted yet? I was wondering how they are.

Had a big FMIC on the track car for years mate, although will be fitting a bigger core at some point when we go ko4 on it!

Federals won't be on for a few weeks yet, need to strip
And refurb the rims, they're currently orange, but will be going black before the tyres are done :)
 
I don't think I'd let jardo drive my car ;)

Not sure I will again!

It was delivered to him by Dad in fully working order, and arrived with me 2 days and 200 miles later with no engine oil, no brake fluid, and a Christmas tree of lights on the dash. Had to fit a new master cylinder the brakes were so ****ed!

J-rod, it's nout to do with you boyo, you just got lucky that idly decided to wake up for you. Shame really, as perhaps if it'd stayed slow you wouldn't have raped the brakes!
 
I don't think I'd let jardo drive my car ;)

Prawn said he's never met anybody with so much natural driving talent. So nerrr!!! :p

Seriously though, I am basically the stig. Ask Prawn! lol!

Also Prawn, I am and was TRULY sorry for raping your car. I didn't mean to break it, it wasn't my fault I promise! Thinking about that road trip home makes me want an A3 for me in a large way...
 
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Prawn said he's never met anybody with so much natural driving talent. So nerrr!!! :p

Seriously though, I am basically the stig. Ask Prawn! lol!

Natural ability with regards to car control : yes

Sense of responsibility or consideration for safety: Nil
 
Natural ability with regards to car control : yes

Sense of responsibility or consideration for safety: Nil

Fact.

I've toned down a lot now, you'll be quite surprised. I CBA with the consequences anymore so I just drive safely.
 
Car is back with me again for a few small jobs leading up to the next track day.

Going to start swapping a few bits around to try and recover some lost boost. Going to start with my LCR 4 bar fuel pump, then change the ignition and fuel pump relays, then if that doesn't work, it'll be a forge actuator

To anyone interested, (plunky? Sportstractor?) I'm doing a trackday at Hulavington air field on July 15th.

It's a huge airfield track with loads of runoff, and a stupidly cheap price for a full open pitlane day at £109!

https://orders.motorsport-events.com/EventList.aspx



very interested in this mate, have you booked up yet?
 
You two are hilarious.

Nick, will you have the federals on for the ring do you think? When do you plan to get the K04 on?


Oh god yea mate, they will be on for hulavington on July 15th, just got to do the bodywork on my girlfriends polo next weekend, then I'm back onto the track car :)

Ko4 will probably happen over winter I think, want a full st2 setup with badger 5 inlet, so hopefully a strong 280bhp+, which will be more than enough with 1065kg!

That, and a roll cage are just about all that's left to do!
 
wow,,,this was a very long but good read, your cars are to a higher class and breed ha :) should be a sticky with all these mods :p

i would of cried after seeing the cracks lol sad times

any new figures on the power status and mods? by any chance

keep it up
 
Not yet matey, will be booking in the next few weeks. Open pitlane for that money is great though, and being an airfield day there's less to hit! Haha


cool, well let me know when you book up and i will too, may need to get another set of wheel and tyres for it though!!
 
Tell me about it man! I was looking at that earlier.

If I'd have sold this black one, and bought Mikes IHI, the money I made stripping the interior would have paid for seats and harnesses, and I'd have an S3 track car instead.

However. This car is part of the family, and that's half the reason we love it so much.

That, and I like to prove a point about the lowly FWD A3's.

Afterall, it can't all be bad if Bill still hasn't moved to 4wd with his ibiza....
 
OK, so I decided to be Brave, and do some highly risky testing earlier to see if my boost issue was mechanical or electrical.

Short of it is, it's electrical.

To test it, I was thinking about how the turbo worked, and how it boosted.

If the turbo was tired, it might not be making the boost it should. Equally, if the actuator spring had gone weak, it's possible that the pressure in the exhaust housing could force the flap open, so reducing boost.

How to test if this has happened?

REMOVE ALL BOOST CONTROLL - EEK!

Basically, disconnect the outlet from the N75 to the actuator. Running like this, the only thing that will limit boost is either the turbo reaching it's absolute peak, or the wastegate being forced open against the actuators spring pressure. No air is bled off to the actuator, and as such, it'll never open.

Now, seriously, DO NOT TRY THIS.

If indeed the turbo is tired, and it won't boost any higher, or the actuator sping has gone weak, then it's probably fairly safe, as the car will still be fuelling for the reduced boost level.

In my case, the test proved that the turbo was still good, with boost SHOOTING straight up to 25psi and holding there. my GOD it was fast :S

Clearly, the turbo is working, so my reduced boost must be something that's pulled back electronically.

The car shows no timing pull, so I can only assume it's pulling back boost due to a lack of fuelling. If that is the case, then running it at 25psi when it thinks it can only safely fuel for 16psi is a pretty daft idea! it has however given me something to hunt for, I know it's not mechanical, and I know the actuator is capable of keeping the WG shut up to 25psi (whether the turbo runs out of puff or the WG is forced open at this point I do not know, but it doesn't matter really either way).

It's worth noting that I only ran it like this for about 1 mile tops, I did 2 pulls in 2nd gear, and a single pull in 3rd gear. Each pull resulted in around 25psi of boost. It's seriously unsafe to run like this, so please do not try it!

So, electrical it is then!

Will start with a 4 bar LCR pump, then ignition and fuel pump relays, then perhaps look into a new MAF and N75 if that doesn't cure it.

Nice to know where to start though :)
 
So what are your problems prawn? Have you tried logging the n75 duty cycle? I know you cant log actual pressure but does it state command?
 
not tried logging N75 cycle yet J, I only got the car back this evening, so need to start testing!

Does anyone know of a list of the block functions in Vagcom for ME3.8?

I've tried a few of the blocks I log on my AUM (ME7) and half of them are unavailable!
 
OK folks, I need advice please!!!!!

I swapped fuel pumps last night, so I've now got an LCR 4 bar fuel pump in there, which is KNOWN to be working perfectly, and fuelling fine for 20psi of boost in the daily.

This made no difference to boost at all. Still around 16 psi.

This morning i swapped N75's over from the daily too, again, this N75 is known to control boost fine up to 20psi in the daily, yet if anything, it has made the track car feel softer! Still around 15-16psi, but not as aggressive at all. Both are N75C valves.

So that's not it.

I've tested voltage at the pump on idle, and it's 13.07v, compared to 14.36 at the battery. is that enough or a drop to cause an issue? is the voltage likely to drop more under load when driving? I'm going to use my ultra sonic cleaner to clean the injectors and FPR this week some time, and see if that helps, but I'm doubtfull.

I've also got a 4 bar FPR on the way to throw in quickly and see if it makes any differnce.

Any ideas greatly welcomed!
 
also, if it makes any odds, I logged block 007 last night on vagcom, and on full throttle, the duty cycle (which i think is of the N75) is pretty much at 99.6% the entire time at WOT)
 
also, if it makes any odds, I logged block 007 last night on vagcom, and on full throttle, the duty cycle (which i think is of the N75) is pretty much at 99.6% the entire time at WOT)

My N75 looked fine when I logged duty cycles but was still shagged but in your case you've swapped over the one from your daily driver so I doubt that's a problem. You need some idea of what to log to be able to see what is restricting the boost.

So the only way you've managed to replicate it running spot on was to run it without the N75 controlling it :think:
 
yea, pulled the pipe off the actuator and it went nuts! But that's uncontrolled boost, so not safe at all.

it proves the turbo is OK though, so the restriction is caused by something else.

Question is what :S
 
yea, pulled the pipe off the actuator and it went nuts! But that's uncontrolled boost, so not safe at all.

it proves the turbo is OK though, so the restriction is caused by something else.

Question is what :S

What is your actuator set at then? When I ran on actuator boost I had 6PSI!!! Surely then this sounds like the map telling the N75 to keep your boost at 16PSI?
 
I didn't bypass the N75 Neil, I actually disconnected it TOTALLY, so it wouldn't open, at all. ever. that's VERY different to running on actuator pressure, where all the charge pressure goes to the actuator and opens it early. the opposite infact.

it is indeed the ECU only wanting 16psi for some reason, the question is, why? it used to make 22-24psi, and that's what it's mapped for, so something isn't working properly, hence it only wanting to make a lower boost.

sadly, the ME3 ecu doesn't have 'requested' boost so to speak, as it's pre historic!
 
I didn't bypass the N75 Neil, I actually disconnected it TOTALLY, so it wouldn't open, at all. ever. that's VERY different to running on actuator pressure, where all the charge pressure goes to the actuator and opens it early. the opposite infact.

it is indeed the ECU only wanting 16psi for some reason, the question is, why? it used to make 22-24psi, and that's what it's mapped for, so something isn't working properly, hence it only wanting to make a lower boost.

sadly, the ME3 ecu doesn't have 'requested' boost so to speak, as it's pre historic!

Ah I get you. hmmm someone else must have had a similar problem. I might stand more of a chance of keeping up with you round the Ring if you're not running on full boost ;)
 
someone else MUST have a similar problem.

I thought it was typical on AGU's until I went in Liams car and his holds a steady 22 every gear every time.

I don't want to bypass the N75 and run an MBC either, because if it's electrically holding it back there must be a reason!

without a wideband it's very hard to know what's going on :S

If you want to keep up on the Ring I could always bring a tow rope Neil?
 
well as yours calcuates boost from maf/ o2 sensor and rpm, could it be possible its one of those. Isnt much else it could be prawno, except fuel pressure :p

What a shed
 
OK. I've fixed it.

I don't particularly want to say how, as I'm feeling VERY stupid right now.

But I'm INCREDIBLY happy, so what the hell:

It was the MAF!"!"""11!!!!!1111!!!!!!******!!!!11!!!!!!!

AARRRRGGGGHH>.

Seriously, it was the maf? I don't get it!

I've always had REALLY good airflow when logging MAF readings, and the car's always run MUCH worse when it's disconnected, so I figured it wouldn't be the maf. I've also cleaned it several times to no effect. So surely the maf was ok? Right? NO.

Popped round to Plunkys tonight, and he very kindly let me try his MAF on my car.

instantly, it was incredible, straight to 23psi, and absolutely FLYING! It felt amazing.

I think, if my theory is correct, that my maf was over reading.

If my MAF over reads, then I imagine the car will see the high airflow, and assume it's reached it's specified boost level, so will pulse the N75 accordingly, so clearly my ECU thinks it's getting enough air for 22psi, and runs the N75 accordingly, when infact, the airflow reading is high, and it's only made 16psi.

I didn't get to do any logs, but with Liams MAF the car was instantly like it was when mapped 3 1/2 years ago.

Absolutely chuffed to bits, just need to get my own new MAF now and I should be back to full awesome ko3S Powah!!!!
 
glad its all ok now mate, car definately felt good :)
 
long time since any update here!

MAF saga is pretty much over, in that I'm sick of playing games with it any more!

4 new MAFs and I've settled on one that pretty much works. not as well as I want, but it's better.

first 2 MAFs gave me no performance increase, so were deemed to be defective, and taken back.

3rd one came from ECP, and gave me HORRIFIC overboost and lean misfire, when logged it was found to be under reading by 40%, hence the ECU trying to compensate with more boost. Pretty nasty stuff really.

MAF number 4 and I've got a bit of boost back, around 20psi now. Tried logging with a Liams again, and it turns out his only makes mine boost a bit higher because his MAF is under reading slightly too compared to mine, so that's not a real fix.



I had a trip up to see a Northloop member in the week, who very kindly fitted my Federals onto my TT rims for me, Big thanks to Bruce for that, nice to meet you too

Those went on yesterday evening, and Dad and I took it for a little test drive, they're a massive improvement over the 205/50 Pzero corsas I had previously, you can just feel that the 225/45's are more suited to the car.

Will get some pics of it today on the new rims.

In other news, Dad and I went to Bruntingthorpe on Saturday, and had a test drive in this:

6de92a87.jpg


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Which was incredible, the Deronda type F. Mid mounted longitudinal 1.8T with an A4 transaxle box, 300bhp and a whole load of fun around the Sprint circuit at Bruntingthorpe!
 
You should definitely try the RS-R's Neil, I'm liking them a lot from intial use. Can't wait to get them scrubbed in and used on track in 2 weeks time!

Fitted a towbar to Dads A4 this morning, what a joy that was :S

Then, this afternoon, in light of my external tap being broken, we went for a drive, and had the car washed.

We went down to the chaps at the train station in Basingstoke, who do a remarkably good job:

89fb74f1.jpg


Then off for a little drive, with a stop for some pics:

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The new wheels are fairly heavy, but when the choice came down to money towards lightweight wheels, or money towards a roll cage, the choice was an easy one to make.....

Plus, I think the new wheels look great on the car too, and the Federal RS-R's seem very impressive so far as well
 
Taking this out tomorrow, so I gave it a little wipe over to get it shining nicely :)

Buffs up ok really for a track car:

53e45ba3.jpg


And a comparison shot against the daily:

2df8bbe5.jpg
 
Very nice mate. Looks a right tough little som b1tch
 
Well, welly saw 340 from this very turbo and same manifold, but my engine has done over 200k!

Its a large port AGU, with 20mm rods as standard, so it's a good base, but for now, it wont be getting rods or wmi. It'll be run at 18psi peak, capped with an mbc, held to the redline, to hopefully give lowish torque, and a smooth delivery of a reliable 300bhp with loads of timing and low AITs
 

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