I have had mixed messages from different people (including a fuel injection specialist) who say there is nothing wrong with fitting VL turbo spec injectors to a non turbo 3 litre engine and the fact they are not massively oversized the ECU should be able to compensate by shortening the injector pulse width at idle & low revs (in closed loop condition).
Others say that it would result in bore wash,poor low down power due to running too rich and the fact it will idle like a pig,also that the N/A ECU & lambda control will not have the scope to alter injector pulse width due to its narrow sensing & self tuning capabilities.
I was tossing the coin around after being on my 2nd lot of second hand injectors in 100,000 kms (which I would expect) as they were leaking as to whether it would be worthwhile buying the aftermarket turbo injectors from the specialist for $110 each or just whack 5 second hand injectors in (1 was o.k.) for $11 each (that's cheap!!),I considered the worth as I am building an RB30DE engine and didn't want to waste too much money on the old setup,so I chose the second hand approach.
On the autospeed website it has small circuitry there to modify the output of a MAP sensor of AFM but I believe this would alter the voltage output overall & affect topend performance as what really needs to be dealt with is the injector duty cycle at idle & low speeds,which is usually changed within the software.
I have been told the VL's are unlike a lot of new cars (I believe that) and do not have flexible ECU & lambda control such as say a Hyundai or BMW,etc which use a wide band O2 sensor which would have better control over injector pulse width.
Vlt injectors flow about 20% more fuel, id say a 16kb vl computer would be pretty rudementry and wouldnt adjust the pulse, its a shame because i had a spare set lying around which i would have given you.
The top end performance would still be pretty much the same ,just concerned with the low down power & fuel economy, hypothetically, if the VLT injectors flowed 20 per cent more and the N/A VL injectors operated at 100 per cent duty cycle on the N/A car then the VLT injectors would be operating at 80 % duty cycle on the non turbo vehicle if being floored everywhere.
I read up the CC rating on the inter - ject website ,it said the N/A VL injectors were like 10 - 11 CC's,this sounds like the fuel delivery at idle rather than 100 % D/C.
The VL turbo injectors flow something like 12 - 14 CC's of fuel.
that is why I figured the that the VL ECU & o2 sensor may have a slight chance of trimming the pulse width down a couple of cc's,maybe 2 cc's is a lot for this type of computer.
One thing I did think of is the air flow meter may have enough scope to try but I don't know.
I am rather very curious than desperate because the car is going better with the second hand injectors I have fitted.
Are the VLt injectors you have any good, or are they on their way out??? If you're ever in the frame on mind to "give" them to someone, I'm always here.
hehe.
Hey russell, it seems that the computer should just be able to sense the engine running rich from the o2 sensor and adjust accordingly.
Alas, this isnt true and i have to agree with carcrazy.
However this might be an interesting piece of information:
If i substitute an N/A computer in my VLT then it runs very rich.
The N/A ecu doesnt know that there are turbo injectors at the end of the fuel rail and it doesnt adjust the pulse width accordingly, also it doesnt figure out that its running itself rich from the o2 sensor, it just keeps on running that way and never doesnt realises that the turbo spec injectors flow more fuel for the same pulse width.
You Have to remember that when our cars were being designed 'pong' was was the most graphically intense computer game available.
