pinging 1jzgte

[jonra23]

A split (pairs or groups of 3) or sequential injection system will give less fluctuation in fuel rail pressure.

There seems to be a fair few 1js making reasonable power with standard ECUs and injection setups, running fuel cut defenders or interceptors so dont think the standard system is that limiting.

Did he say what the fuel rail pressure was at when the injectors were maxing out?

regards
jon

[EldarO]

Wildsupra was making 297 rwhp on stock fuel system, wasnt close to leaning out dangerously.

sounds like you need a hellofvalot more fuel rail pressure, but what the tuner said sounds plausible.

Eldar.O.

[lojik]

From memory he said the pressure was around 45psi. But I doubt that was tested under load, probably only at idle/standstill.

Yeah I think it what he is saying is plausible, I just think it would only become an issue if I was trying to squeeze ever last bit of power from the system and not at the power levels I'm at.

Perhaps a new fuel pump is in order.

[Enchanter]

You mentioned you have upgraded your fuel pump already, there are some dodgey chinese rip offs posing as quality pumps going around at the moment, you may have one.

On another point does the stock ECU really only batch fire all the injectors together in one go ? I would have thought it would at least fire in batches of three.

[lojik]

I'm not sure anyone has stated the stock ecu runs batch fire injection. I have a haltech e6x, and don't have enough outputs between the ignition and the injectors to run any more than the batch fire. (I think I could use an additional ignition device to change this though)

The pump I have was in the car when I bought it, so I'm not sure where it came from.

I won't be taking my car to a workshop again any time soon. my arse is still sore from paying my bill this morning :-o
That money could have been much better spent.

[lojik]

*double post removed*

[nick.parker]

Ignition advance: 13.00
RPM: 4643
Injector DC: 93.7
Injector time: 9.257

4643 RPM leaves nearly 26 milliseconds (two crank revolutions per cylinder, per cycle) to inject fuel. My question is how is 9.257ms out of a possible 26ms = 94% duty cycle?

Have you verified with a timing light that at idle for example the the ignition advance that the engine has matches what the ECU says? This is an easy trap even for me when I adjust my exhaust cam and then forget to adjust the dizzy on my 4A motor!

Also what the other guy said, get a wideband AFR meter. Some Dyno tuning places have innacurate and out of calibration wide band setups.

Edit: OK so if injection isn't sequential but 3 batched pairs then 2 x 9.257 / 26 = 71% duty cycle, which is still less than 94%

[Enchanter]

I'm not sure anyone has stated the stock ecu runs batch fire injection. I have a haltech e6x, and don't have enough outputs between the ignition and the injectors to run any more than the batch fire. (I think I could use an additional ignition device to change this though)

The pump I have was in the car when I bought it, so I'm not sure where it came from.

I won't be taking my car to a workshop again any time soon. my arse is still sore from paying my bill this morning :-o
That money could have been much better spent.

I thought I read someone comparing the stock ECU with the Haltech regarding fuel delivery and saying it should be fine but I must have been too tired because it doesnt say it now

It looks like your problem cant be solved by a simple retune, cleaning the inj may be enough to fix the problem though, thats the direction I would go knowing there is no fuel filter.

[EldarO]

he said hes had his injectahs cleaned etc. etc. didnt help.

change out that pump, it sounds sus, and with walbro's going so cheap (importbitz FTW) it would be worthwhile freshening it up anyway, as a bit of preventative maintenance, as the old pump maybe be 15+ years old by now.

Eldar.O.

[lojik]

It has a walbro in it already, I think its only 2 years old or so.
They can die though I suppose.

It's not pinging anymore though which is nice, though thats probably since boost was cut back a little.