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557 BBF Timing go efi 1200

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Needing help on timing for a 557, ported eddy heads, to 300cfm? do not have flow sheet though. 10.5 comp for 91 pump gas

MSD 2 wire locked out dizzy, intank pump, # 8 steel braided lines

I set initial at 11.5 on dizzy, and controller I have been told that all in should be around 32-34 but when I check it with a light it is around 38 39, hand held is all over the place here is a data log I didn't rev it high, not sure if I am even close the way stuff bounces on the data log.

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Ed FIck

Are you using timing control?

Yes I am, at least I am trying to. In my old world, I would set my all in timing with a light,  as long as it started well, that was pretty much it.  It is starting ok, but is bouncing 16 to 20 idle and just off idle. It seems to be building more heat than normal? I understand the AFR will teach its self, but not timing. that is why I am being cautious. I tried to upload a data   log, but it said I didn't have permission on here. I did around town driving up to 4 k rpm

Ed FIck

AFR does not teach itself.  The unit will teach itself to manage the AFR you have commanded.  You still set the AFR.

My procedure is to set the idle AFR much like you would a carb.  Using idle quality and vacuum to get close, then fine tune to the plugs.  Once a baseline idle AFR is established, you build your tune accordingly.

Timing does move around a little.  Common with electronic timing control.

Sharing a datalog.  You must use Dropbox to share.  It is a free file sharing app.  We use this to share software also.  Same as Fitech.  Once you have an account, transfer the datalog file to your Dropbox account.  Select 3 dots next to file name, select share, then create link, copy to clipboard and paste on next post.

Thank you, I think I have the data file.  As far as the tuning n the afr? I am at square 1 I'm afraid. The vacuum  thing?  So am I adjusting what, to get highest vacuum?  On snowmobiles we tuned plugs to a light toast color? What is plug timing, as where the color is? thank you for your patience and insight

https://www.dropbox.com/s/ev34lnjga3swvyr/DashBoard3%20%20long%206%201%2019%20%204k.csv?dl=0

 

Ed

Ed FIck

Your log is not looking bad.  The unit is still doing a lot of learning.

As for tuning AFR, you should do some research and reading on that.  You need to know the basics of tuning before tuning the Fitech.

When I am adjusting timing for best vacuum, is that adjusting with dizzy and light or with the adjustment on the handheld?

Ed FIck
Quote from Dman20 on June 9, 2019, 6:24 pm

When I am adjusting timing for best vacuum, is that adjusting with dizzy and light or with the adjustment on the handheld?

You only set your base timing with a timing light.  Lock your timing on the handheld, then match your timing marker to base timing setting.   From there all you timing settings are done from handheld.

So yes and no.  I would set your base timing at the default Fitech value.  Should be a good start.  Then start adjusting the AFR for best vacuum and idle quality.  Fine tune to the plugs.

just my 2cents worth but when you set ALL IN timing you should be setting it to true tdc  I have a 545 blown dual power adder I used a dial indicator through the plug hole to attain true tdc, then I used a msd timing tape to ref 0 degrees on my lower v belt pulley and engraved the marks from there to 40 advance, with all the parts in the motor and tolerances for piston pins rod bearings crank gears I s the reason for the variance but before you actually mark 0 degrees measure the free play from left to right in the crank rotation divide that by 2 take that number and adjust where 0 is on your crank now you are near perfect tdc or 0 degrees my dizzy is locked I set my all it timing at 38 degrees and for starting I am using the msd 3 step retard it has a 25 degrees retard on start that puts me at 13 degrees on start I am also using the 6al box I am also using the taylor 8.8 wires and a cold plug,, I never even looked at the fitech timing specs or control and or adjustments I do not have the connected  also I see a miss matched part your cam is a thumper cam the fitech needs a cam that is capable of making at least 8 hg of vacuum at or between 600 to 1100 rpm with you iac at 8 -10  you lobe sep is 107 it should be closer to 110-112 I am using a comp 112 lobe sep cam and make 14hg

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Deleted user

Thank you, A little confused on the mismatched part comment> do you mean the cam is miss marked, or  are you saying the fitech isnt compatible with the cam? It idles with between 8 and 9 inches of vacuum at around 950 rpm. With an external vac gauge? This is coming off the front vacuum port, as the intake doesn't have any ports.

Thank you for your response.

Ed

Ed FIck
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