Need advise please
I have a 1200pa on a SBF 347 with Victor jr intake, AFR renegade 195cc heads, Comp cams XR286R 050 in248 ex254, duration in286 ex292, valve lift in614 ex621, lobe 110 mech solid roller. C4 auto with 3000 stall converter.
Cold starts just won't happen unless I hold the pedal open, I have the crank IAC open all the way and the prime shot is -100, I have tried putting fuel in on the crank fuel 20f at 23 and 65f at 35 which I thought did help but now seem's to make no difference at all.
Kinda got fed up playing with the cold start so got it up to temp and had a go at throttle response which when you blip the pedal 3 times in quick succession it coughs and stalls.
So before I screw something up I thought I should see if you guys could point me in the right direction.
I did reset it back to default and put in all my details as above as this was on a BBF 390 before I got it but it was ok on that, I remember that it was on 179 prime shot and 65f at 25, 170f at 36 but these did not work for me. I'm working on the basis that I have to much fuel going in due to having to use the pedal so have been taking out fuel form the various settings.
I'm not going to give up on this and will get there but could really do with some help. I've never been involved with EFI before so I'm a total novice.
Thanks Eddie
We will work this out. I should be able to work this out. Thanks for the detailed engine information. That's a good start.
What do you have your cam setting at on handheld?
Is the Fitech keeping the memory of your settings? Sometimes they have Alzheimers when new or big changes are made...
You may be trying too much at once. Maybe not. This is the limitation of diagnosing and fixing online. Let's start here. Get engine started and let it get to operating temp (above 170). Confirm from handheld. Check and/or set your IAC steps around 15. Then datalog for 30 seconds at idle only. You can post here with Dropbox or Cloud.
Austin,
Thank you for your assistance.
Cam was set on 3 now but I now have it on 4 as I read a post where the guy was having similar issues and was asked the same question, he gave his spec and was told he should be on 4 as his cam did not produce much vacuum, his spec was very similar to mine.
Yes it does keep it's settings.
Will set around 15 IAC when I get home from work and data log it.
Cheers Eddie
It will be either cam setting 3 or 4. We will get a better idea when we see a log.
The more radical the motor, the more care in the tuning needed.... The great thing is once you know how to read the data, tuning becomes very easy and less time consuming than carb tuning.
Sorry there like this, asked my son to help out and this is what I get back, I did three 30 second logs at 170/180/190f
It was very compacted before so it helps me see the different values for each, please do to them whatever you need to.
There is another log at approx 15 IAC that he will do later but hopefully this will give you an idea.
Thanks
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The last four.
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That is looking pretty good. The unit is learning. At that vacuum, I would normally say cam setting 3, but the fuel trims aren't too bad hear. The IAC is a little high, but not out of reason. If the engine likes this setup, let it learn. Take it for some short drives with normal throttle. Be patient. I gaurantee, if you mash on it now, it will fall on its face.
Study up on how to adjust your Accel. Very easy and can be done whils driving. This is where you will see the advantage of tuning electronically instead of tweaking a carb. The Fitech website has some really good information on setting Accel.
I have some time on Sunday so will clock up some miles.
Here is the log when at 15 IAC.
Made a small donation, hope it helps with the site.
Thanks for the advice.
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I really appreciate the donation. Glad I can help. This site is starting to take on its own life. Looking forward to having a community of users commenting and solving issues. I don't know it all....
Hope to see some good news as you drive it. Keep us updated.
What is your fuel pressure at idle?