CLASS RACER FORUM - View Single Post - Holly HP EFI-- Idle & IAC Tuning

Robin Lawrence · 03-01-2021, 03:05 PM

Just saw this post. Bradenton-SGMP-Bradenton I haven't had a chance to respond. I agree with the suggestions above.

There are many ways to make them happier but they are a little more complicated.

One things is be sure that the injector data is correct. Voltage Offsets if wrong can make the injectors inconsistent in their operation.

Another is to look at your target idle speed. Be sure that the TPS reading returns to 0 or 1 at the idle setting. If using Idlespark it needs to be within 200 RPM of the target to work well.
Idlespark with chase the idle speed with timing up or down 8 degrees.

If it doesn't start well your cranking fuel or timing might need some work. Also after start enrichment for the first 100 seconds or so after startup.

If using the closed loop function on a stocker with no exhaust you need to turn it off util a higher flow through the collector. Anywhere from 4000 to 6000 RPM. Below that you will need to massage the fuel table to make it happy in open loop.

That's a good start of several things to look at.

Robin

03-01-2021, 03:05 PM	#5
Robin Lawrence Sponsor Join Date: Jan 2002 Location: Galesburg IL. Posts: 161 Likes: 212 Liked 622 Times in 108 Posts	Re: Holly HP EFI-- Idle & IAC Tuning Just saw this post. Bradenton-SGMP-Bradenton I haven't had a chance to respond. I agree with the suggestions above. There are many ways to make them happier but they are a little more complicated. One things is be sure that the injector data is correct. Voltage Offsets if wrong can make the injectors inconsistent in their operation. Another is to look at your target idle speed. Be sure that the TPS reading returns to 0 or 1 at the idle setting. If using Idlespark it needs to be within 200 RPM of the target to work well. Idlespark with chase the idle speed with timing up or down 8 degrees. If it doesn't start well your cranking fuel or timing might need some work. Also after start enrichment for the first 100 seconds or so after startup. If using the closed loop function on a stocker with no exhaust you need to turn it off util a higher flow through the collector. Anywhere from 4000 to 6000 RPM. Below that you will need to massage the fuel table to make it happy in open loop. That's a good start of several things to look at. Robin __________________ STK 308 SS 3088