S2 Performance Questions

[dm80]

Any ideas as to where I can get a 'homefry' chip in my area? (central Scotchland).. There's a place local to me http://dastek.co.uk that will do a Unichip.. Anyone had any experience of this type of 'piggy back' chip?

[Greg_S]

i'd steer clear of a piggy back chip if I were you. there is starperformance up in scotland and doug who is part of MRC is from that area too

[S2central.net]

Yep - piggy back chips are bad news in my opinion - nothing more than an ugly hack. I've sent you a PM about the homefried option... The spare ECU is ready for duty again - just came back from the previous job last week.

Paul

[Jamo]

Any ideas as to where I can get a 'homefry' chip in my area? (central Scotchland).. There's a place local to me http://dastek.co.uk that will do a Unichip.. Anyone had any experience of this type of 'piggy back' chip?

It works very well on certain cars but for the S2 don't do it, contact S2Central for a homefry chip, he can offer exchange ecu or contact Doug_RS2 at MRC for a real time remap of the car

[Jamo]

Yep - piggy back chips are bad news in my opinion - nothing more than an ugly hack. I've sent you a PM about the homefried option... The spare ECU is ready for duty again - just came back from the previous job last week.

Paul

Eh? lol that wasn't there when i posted!

[Simon]

Please don't dabble with boost controllers and fudged temp sensors on the S2 - it is NOT the way forward. I see some of the lads here have already mentioned the home grown remap available from myself.

This retains all Motronic failsafe mechanisms, factory diagnostics but has more aggressive timing and fuelling to go along with increased boost levels (Max 1.4bar) that give the S2 a lot more edge. You'll find the car much more torquey in the mid range and a lot more oomf at full throttle. Homefried cars have been dyno'd at 270-280bhp and 410-430Nm. Fuel consumption is also slightly better (if you can go easy with the loud pedal).

Paul

Sounds interesting, I'm thinking of a boost controller to counter the wastegate creep and give it more bite, the turbo seems a bit puny to be increasing the boost... Is this a reversable plugin chip replacement, or so I need to damage the ECU? and how much power is at the wheels?

Thanks,
Simon

[Simon]

Slightly sorted the running problems, the ISV I removed rattles so presumably was the main cause. No error codes via blink, can't get my hex reader to work without an additional interface and can't find a diagram or the active pins. Don't suppose it matters though.

Whilst running is now fine, boost guage (tried 2!) reveals its maxing out at 7/8psi and then in the low revs. Can't hear any leaks (this much should be audible???) and thinking the dumpvalve is probs not closing fully, changing it on the off chance this weekend. Are there any other obvious things I've missed....am I right to assume a leak? Is there anything which doesn't generate a fault code, which would cause the ECU to limit boost?

Thanks,
Simon

[BRY]

WGFV is it connected?
Is it working?

[Simon]

WGFV is it connected?
Is it working?

Dunno, haven't replaced this....I thought this was covered by the diags, but I've just found the thread on testing.

Ta,
Simon

[Simon]

WGFV is it connected?
Is it working?

No its tossed., so much for diagnostics.

Using a manual controller whilst I wait on a replacement. People seemed to thing this was a bad idea, just curious as to why. Boost is instant, sticking with 1.2 currently, throttles itself back (fuel pump?) when you run too much, its happy with 1.4 but getting a little hot. Ragging round all afternoon once we'd got is set up. Its still only peaking with late 190s bhp down though, does anyone know what a stock ABY (Avant) puts down normally?

Ta

[Fat Audi 80]

230 bhp for a stock aby....

[4WheelDrifter]

@Simon - How are you controlling the boost at higher rpm?

[S2central.net]

No its tossed., so much for diagnostics.

Using a manual controller whilst I wait on a replacement. People seemed to thing this was a bad idea, just curious as to why. Boost is instant, sticking with 1.2 currently, throttles itself back (fuel pump?) when you run too much, its happy with 1.4 but getting a little hot. Ragging round all afternoon once we'd got is set up. Its still only peaking with late 190s bhp down though, does anyone know what a stock ABY (Avant) puts down normally?

Ta

What fudge factor for transmission loss is your g-meter using? From memory those things assume 2WD and therefore 15% - you need to make a correction for quattro with 25%. Do the math...

Boost controllers have limited scope - the K24 will boost happily to 1.4bar in the mid range - developing peak torque - but it REALLY runs out of puff at about 0.8bar on the redline cos it simply doesn't have the efficiency required to keep air temps within sensible limits.

The 'throttling back' you are feeling at high revs at 1.2bar is KNOCK - the ECU retards timing as you have dialled in too much boost with this controller.

As a bare minimum, a boost controller has to be able to reduce boost levels at high revs - does this thing have an rpm input ? Would it understand the 5-cylinder beat anyway ?

Boost controllers are flawed for that reason and the other minor detail that they cannot change ignition timing - or fuel injector openings. All you get is increased fuel pressure in line with boost, but with stock ignition, injection and correction maps you will never realise the gains from a proper 'sports' chip upgrade.

Some suggestions:

1. Throw the boost controller in the bin - or give it to someone with a Renault 5 Turbo (whats the difference).

2. Fix the WGFV and associated control hoses.

3. Check for boost leaks and verify the stock ECU pulls 1.1-1.2bar max in mid range

4. If you want to understand something about turbos then checkout this paper what I wrote about a year ago - its overdue an update...

http://s2central.net/Turbology_v4.pdf

If you aren't happy with how the car runs on stock chips, then send me or Mihnea a PM about revised chips for the S2.


Paul

[Fat Audi 80]

Some suggestions:

1. Throw the boost controller in the bin - or give it to someone with a Renault 5 Turbo (whats the difference).

LMAO

Some good advice in there as always Paul.

Cheers,

Steve