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EightStack Ignition Table

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Does anyone have an larger v8 ignition table they are willing to share?

I have my system up and running and have had the base dyno tune applied. Looking to tweak the ignition table and have some questions. System is a Ford FE (427) with EightStack (Individual runner) injection and a Performance Electronics ECU.

1) shouldn't the ignition timing be essentially the same as with a carbureted system? The car/motor ran well with carburetors using a 14 initial, 38 total, all in at 3000rpm.

2) looking at my new ignition table, it is "smoothed" so at 100% throttle, at 3000rpm, timing is 33.5 degrees and it doesn't reach 38 till 6000. Shouldn't it be some sort of curve between 1000 and 3000 from initial timing to 38 and then 38 all the way across from there?

3) looking at the table, shouldn't all the fields above 3000rpm be "38" and all the adjusting be going on between 850 and 3000 rpm?

I've attached a PDF of my ignition table and hoping someone can point me in the correct direction.

Thanks

Paul

Attached Files

Where is your peak torque achieved? it looks like someone may have went super safe on the tuning

Chris,

Yes, they did go "SuperSafe" on the tune. Max torque was made about 4600 rpm.

I know there is more in the motor, but I told them I was after driveability rather than a bragging rights number. He commented he set it on the very conservative side.

Long discussion with the manufacturer of the ECU, and his employee, who used the conservative numbers. Little bit more knowledgeable but sure wish I had another similar style table that I could see how they addressed the different ranges and curves.

My system runs in Alpha-N with MAP compensation. The range along the vertical axis, whether TPS% or KPa are still just an indicator of the load being applied to the engine. Getting confused by all the tunability the EFI system provides (625 cells) over what a simple distributor with very limited range gives.

I see the guys are getting ready to run a webinar on a system using Alpha-N, but it's not till later this month. Any previews Andre or Ben?

Any articles or past webinars on timing tables?

Paul

The alpha-n guide will primarily be about the fuel side of the tuning as the ignition tuning isn't substantially different to using a MAP-based load input.

You should find that the optimal ignition timing will be pretty similar between a carburettor and EFI and I would expect the engine to want more timing at low rpm - The dyno is really the place to find out exactly what the engine does want though. If the engine does in fact want 38 degrees at full load, you could reasonably expect that it will want more advance than this at very light load too. This would improve part throttle torque and throttle response.