Please help me with my idle tune

Tuning The Delco In Realtime
Posts: 29
Joined: Tue May 17, 2016 11:01 pm

Re: Please help me with my idle tune

Postby h4x0r » Sat Nov 25, 2017 9:01 pm

Thanks Dylan!

Searching the forum for explanation and may have found the reason: viewtopic.php?f=7&t=1712&hilit=ideal+gas&start=90

I think my single/double fire settings may be the issue. I will try again tomorrow.

Site Admin
User avatar
Posts: 4869
Joined: Sat Feb 28, 2009 8:34 pm

Re: Please help me with my idle tune

Postby antus » Mon Nov 27, 2017 4:16 pm

Yep, when adjusting the cranking tables just do it as a % change from stock relative to how much larger your new injectors are, or your new fuel requirements are. Eg if stock is 19lb, and you've upraded to 60lb, you want ~ 1/3rd the amount of fuel. So in tunerpro adjust the whole table by selecting all cells and do multiply by 0.333 to reduce the time down. That should do it, but you can tweak up or down a bit if you find its not good enough.
Have you read the FAQ? For lots of information and links to significant threads see here: viewtopic.php?f=7&t=1396

Posts: 29
Joined: Tue May 17, 2016 11:01 pm

Re: Please help me with my idle tune

Postby h4x0r » Wed Dec 06, 2017 2:51 pm

It was getting practically impossible to start the car so I went back over all basics. The too rich crank was fouling the spark plugs. So I removed and cleaned them. I also put another fuel pressure regulator on just to make sure and went back to stock tune & injectors. Car started and ran perfectly fine at all temperatures. Ok good now back to the siemens deka 60lb injectors. I reduced both crank fuel tables to 1/3 and changed the injector flow rate to 0.048. I also found a different battery offset table from an old post which looks like it would be a little leaner for these injectors. See picture below:

crank fuel edit.png


Car is running again on the 60lb injectors but it is harder to start the warmer the engine is. It takes more time cranking when it is warmer before it finally kicks over. My question is how is crank fuel calculated? because in that picture it is very high 6.84 bpw when I first turn the key to crank. The car idles good at 3.00 bpw which is 1/3 of what the stock tune & injectors would use. Whats the difference between first stage and second stage crank base pulse width and how does it work? I need to lean it out as the engine gets hotter. I'm guess this is the case because the Injector BPW is way above its happy 3.00 pbw idle?

Site Admin
User avatar
Posts: 4869
Joined: Sat Feb 28, 2009 8:34 pm

Re: Please help me with my idle tune

Postby antus » Wed Dec 06, 2017 6:52 pm

Those tables only apply at cranking, and are a raw time value. If you need leaner subtract more. It'll only use those tables at less than cranking rpm i believe which is by default less than 400rpm. You may need to adjust the shape of the table. Try stock shape but subtract an offset rather than divide. Maybe your injection times are ending up below or about the injector minimum.

Looking again the fuel difference between low and high on those injectors will be huge. Try setting them closer to flat but a gentle slope.
Have you read the FAQ? For lots of information and links to significant threads see here: viewtopic.php?f=7&t=1396

User avatar
Posts: 9096
Joined: Sat Feb 28, 2009 9:05 pm
Location: Tenambit, NSW

Re: Please help me with my idle tune

Postby Holden202T » Thu Dec 07, 2017 3:40 pm

keep in mind, stock injector is 19lb @ 43psi or something like that .... make sure the injector you have is the same pressure, and also note that while 20lb is 1/3 of 60lb, 19 is slightly more .... so you might still be on the rich side for the injectors.

I've always had issues with my brothers V6 commodore, running methanol and big injectors, it starts great, but its very susceptible to flooding with a rev when cold, theres a lot of little settings like AE etc which all come into it

but that said it sounds like you are definitely on the right track with it!

Previous

Return to Realtime Delco Tuning

Who is online

Users browsing this forum: No registered users and 2 guests