Priming, cranking and afterstart with 750cc injectors

[button]

Can you look at this config:

http://www.sendspace.com/file/n0v2vg

I can't cope with the normal starting of the engine. Whether the engine is warm or cold I have a very long spining time and move the throttle to start the engine. Sometimes, when the engine for a long time will not catch, after start it able to show a trigger error.

Injectors are LowZ 750cc/min@3bar with series resistors.

[button]

Does someone have any idea?

[gnutz2]

Low Z injectors tend to be c r a p.

What size resistors do you have in series, any thing more then about 2.5 ohm and they will struggle to open properly.

Resistors need to be about 35 watt too.

Personally i have wastad a lot of time and money using these injectors, i wouldnt even go there again.

[pnanassy]

Controlling them is the key.What ECU do you have gnutz?DTA?

[button]

I use VEMS.

What size resistors do you have in series, any thing more then about 2.5 ohm and they will struggle to open properly.

I have, in this cars ~7.8ohm 50W resistors.

When the engine start's it running realy good, and it haven't got problem with idel rpm.
Here is the screen form priming, cranking and afterstart setup:

[gnutz2]

Controlling them is the key.What ECU do you have gnutz?DTA?

Yes DTA, i spoke to allan the technical guy at dta and he told me to use 2.5 ohm resistors.

The engine ran ok but nothing like as good as when on seimens 630cc high z.

I also had a really serious problem with the injectors leaking fuel into the engine when not in use. This caused misfires at best and also caused a fire.

[pnanassy]

Yeah,DTA is not the best when Low-Z injectors come into the picture.However,more advanced ECUs control them easily.For example i got 1200cm3 on my 2.2L I5 and got a nice idle 1.00lambda.

To the hardware issue you had,i dont think its a low or high Z related...

There are special low Z injector driver boxes,worth a try?!

But sure,the new tech. high Z injectors are good.Just experimenting with a 1000cm3/4bar on the stroker.Looks ok so far.

What was the PW where you had problems?

[button]

http://www.sendspace.com/file/9aa1ne

log from starting the engine (unsuccess)

[gnutz2]

Yeah,DTA is not the best when Low-Z injectors come into the picture.However,more advanced ECUs control them easily.For example i got 1200cm3 on my 2.2L I5 and got a nice idle 1.00lambda.

To the hardware issue you had,i dont think its a low or high Z related...

There are special low Z injector driver boxes,worth a try?!

But sure,the new tech. high Z injectors are good.Just experimenting with a 1000cm3/4bar on the stroker.Looks ok so far.

What was the PW where you had problems?

I only ran them outboard so never had to idle the engine with them. the P/W was allways from about 5 to 10 ms.

Like you say maybe they are just bad for DTA.

[button]

Maybe someone would like to share with his own settings of priming cranking & afterstart?

[button]

OK. Problem solved. The problem was in the injectors. After instaling Siemens 630cc/min the engine starts up

[pnanassy]

what was the problem with the 750's?

[Jamo]

Low resistance injectors with resistor packs, i'd say there was a driving issue

[pnanassy]

Im running 96lbs with 4+ bar fuel pressure,and resistor pack.Car starts for the first crank.

Low resistance injectors with resistor packs, i'd say there was a driving issue

[Jamo]

Not all resistor packs are created equally, I wouldn't entertain using them

What's the point of having low z injectors if your have to run resistors with them?

That's why I bought high resistance 750cc RC Injectors