My UR-S4 Boost pressure

[Knight Rider S4]

As above i hit 2.4 on gauge with Homefry

[jd2]

does not sound good The chips were via QRsport, they pulled some files for the s4 and burned them to some chips. I was surprised that the most I got was 1.7 bar when it used to overboost to 2.0 bar. Saying that the boost is much smoother than before and as I said the boost does not drop off like the standard chips did. Id be interested in trying out some other chip sets though are there any sources on this forum?

[merlin's S4]

does not sound good The chips were via QRsport, they pulled some files for the s4 and burned them to some chips. I was surprised that the most I got was 1.7 bar when it used to overboost to 2.0 bar. Saying that the boost is much smoother than before and as I said the boost does not drop off like the standard chips did. Id be interested in trying out some other chip sets though are there any sources on this forum?

It's bound to pull smooth because you're only using mechanical boost so there's no feeling of the wgfv taking over or overboost mode kicking in! How did I know you were gonna say QRSport! I've BTDT with their "chips". I'm not about to discuss the issues I've had with that company on a public forum but I will say that I got a partial refund for my chipset. Took me two years mind!! BIN THEM NOW!!!

[4WheelDrifter]

QRSport chips?
I hope they're not still selling that Digitec *****.
Take them out and burn them as soon as you can!

[S2central.net]

jd2 - you got some issues there. Boost is supposed to drop off towards the redline - otherwise the air just gets crazy hot in the short term, but long term you will kill the turbo.

However the weird boost profile you state with 1.7bar and max and 1.3bar ABSOLUTE is very very low. Thats 0.7bar boost maximum and 0.3bar at the redline. Not the best bit of performance enhancing boost regulation I ever saw in my life. Clearly the WGFV is connected to the ECU or you would just see 1.3-1.4bar on your digital guage all the time (with a standard WG spring).

Send me a PM if you want info on my homefried conversion for ABY and AAN engines - the AANs run a different brew of software due to the smaller intercooler and lower knock resilience... But in short that will give you 2.4bar max boost on your digital guage dropping to 1.8bar at the redline. These have been dyno'd at 270-280bhp and 410-430Nm with Optimax or better fuel. MPG is better at cruise. All of the above requires a basically healthy engine and fuel supply - chip upgrades never solve engine problems by some miracle. My chips retain ALL factory diagnostic routines and any IMMO functionality provided at the factory.

You WILL notice a difference (cough). Plenty of happy customers on here from around the world. Ask around or do a search to see the history. Arguably the most bang you can have for your buck in terms of ABY/AAN upgrades.

Paul

[Knight Rider S4]

Can agree more with the Paul ...I had superchip in mine and was crap ........massive difference now with homefried conversion much more pull (caught speeding ) and better on petrol and other thing i noticed was the car is not overheating as it use to when been driven hard

[PeteRR]

Well, I had a bit of a fiddle around the S4 engine bay today. First thing to do was set the accelerator cable so that WOT is acheived whilst checking the TPS clicks when settling back to idle.
I then had a good look at the vac pipes at the back of the engine (near the Coil plugs). The two hoses on the moisture trap were found to be a very loose fit and just pulled off very easily, despite the clamps looking tight. Replaced them with new clamps, now nice and tight.

Took the car out and got her fully warmed up. What a difference! The auto now 'kicks-down' much more eagerly and the car is a lot quicker than before. Looking at the boost gauge it now goes to 2.0 bar (was 1.7 max before).
Still a bit of checking to be done then as I hoped to see at least 2.2+ bar due to the chip.

After a couple of full acceleration tests, she 'missed' slightly under boost and wouldn't go above 1.3 bar.
However, after a couple of miles crusing she was back at 2.0 bar with no 'missing'.
Overboost protection?, another small airleak possibly.

I'll have another look over it tommorow, but check those vac hoses guys!

[K7ERG]

Chips for AAN engine

How much?

Craig

[topsparky]

mine's the same pete i got a max of 1.9 bar once
but i can't get it t go above 1.7 bar now
i'm gonna do a boost leak test when i've got
time.but try and not blow my maf up

i think i've found my boost leak .its coming from the dv not the pipes but the dv itself
so will have to ring milltek up and get them to change it
going to do my vac pipes when i get round to it