13 replies to this topic

[87vr4]

iv had some issues with how my fuel system was set up latly which iv rectified, but because of the deubious setup that was, its been tuned kinda strange...

after sorting that out iv been monitoring my 02's & under full load is giving me reading anywhere from 12.5 up to 14.1 under full load @ 6k

baring in mind this is a narrow band sensor & iv also got one of those silly autometer afr guages which reckons those kinda readings are rich... ( my turbo timer does afr numericaly)

what kinda number do ppl with stock setups get ?

[Entaran]

12-14.

[87vr4]

nice

[brisvr4]

I've set mine up for 11:1 Paul.
Mind you I have a true wideband so I don't have to trust the crap narrowband

[jett]

I have my car (VR4 4g63) tuned to 15.5 for cruise and idle, 12.5 up to 6psi and then 12 above 6psi...

This is excellent for fuel econ (9L/100kms) and still waay safe at high load....

you will find that 11 is a bit rich and that leaning it out a bit will give you more power - but running an EGT with your AFR meter is the best way to tune - as you can lean it out safely.

[brisvr4]

I'm still playing with it to find the best afr's across the range.
Not too sure about running to 12:1 under boost as I seem to be getting a bit of knock happening over 11.5:1 or so.
Tuning SUCKS! lol

[jett]

i'd check your timing - if its still pinging at 11.5 then most likely timing is the problem... What ecu you running?

[brisvr4]

Stock ecu, timing is generally set at 5deg.

[jett]

No i'm talking about the actual timing where its pinging - like the timing map... not your base timing. Are you running high boost - because the factory timing map should be pretty good up to about 15psi

[brisvr4]

Ahhhh, will do a couple of runs to see what its knocking at

Atm i'm running around 19psi on a big 16g, 560 evo injectors and a 2g maf.

[jett]

i'm running around 19psi on a big 16g, 560 evo injectors and a 2g maf.

On a stock VR4 ecu? Has it been chipped for these mods?

Hard to tell without seeing the maps myself - but i would say that a big16g at 19pound would need far more retarded timing than the stock VR4 timing map. Running really rich AFR's may go someway to cooling cylinder temps and stopping pinging but its definitely not the best way to fix it.

If want to run that sort of boost you need to make sure you do it safely - I would say its time to chip your ecu and get some better timing maps or go for a full after market system...

[87vr4]

how much was that wideband tim? & what do u use to give you the readout? cos the widebands dont output a linea voltage like the narrowband does.....

id love to get an egt meter... but $$$

i still think im having fueling issues, i dont have any audable detonation & theres no sign of it on my plugs... but its hesitating a bit up top on full load still. i really need a surge tank!

[brisvr4]

Hey Paul
The one I have is the AEM wideband.
Cost me about $350 delivered a while ago.
I've got the sensor mounted in the front pipe just near to where the aircon compressor is.

I use MMCD to log it, that won't help you with the Haltec though...

[jett]

Zeitronix is also a good unit - Close to AU$500 landed though. But it comes with the whole deal sensor, controller, software, loom etc. You can also input RPM, TPS, Boost, EGT and an AUX and display it all on the same realtime graph. Extremely handy for finding exact tune points. Eg. You can do a boost run and then look at the graph and find the RPM and load points which are out...

It also has an output to send the AFR to your ecu...