Fuel Injector comp.

[98spydert]

Two questions here. I'm all about drivability and comfert when it comes to my car so these may be a little strange to all out racers.

First: Out of the pintle and ball style injectors, which functions better at idle and low rpm? I know the ball style are supposed to be much better at high duty cycles but is anything sacraficed? Is there any difference in the two?

Second: When choosing 550cc, 660cc, 720cc or whatever, at what size does it negatively effect idle and low rpm if any?

 

[kpt4321]

There are a couple of reasons why larger injectors effect idle and cruise:

1. Deadtime. As injectors get larger, it takes longer for them to open when you send them the signal to begin firing. The ECU is programmed with the dead time of the stock injectors, so when the deadtime increases the ECU won't be opening the injectors for as long as it thinks it is.

DSMLink and 1g EPROM chips (www.dsmchips.com or custom) will eliminate this entirely.

2. Timing. When you use an airflow correction device like a SAFC, VPC, or a MAFT to lean thet car out, what you're really doing is telling the ECU it's getting less airflow. This will generally give you more timing advance. Too much advance can cause problems, like part throttle knock.

Again, DSMLink and EPROMS take care of this.

Hope that helps.

 

[98spydert]

Thanks for the reply but I already know all of this. Have any thoughts on my two questions?