Author Topic: Help for ignition map needed  (Read 22326 times)

Offline MadsF

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Re: Help for ignition map needed
« Reply #15 on: October 20, 2016, 03:25:44 pm »
Well firing the spark close to top is the same as advancing in my head, isnt that what i want to do? Otherwise i am completely wrong about what i understand about this. I though that a spark fired closer to top equals less pressure on the upward motion of the piston which should reduce the stress on rods and knock aswell.   :o
More ignition advance makes the firing farther from the top.. The closer from the top the hotter the EGT. So there is compromise for the ignition advance to reach between the risk of detonation and a too high EGT  temperature, I think.

Oh okay, i just understood it as the exact opposite  ???

Anyhow, i still get the basics, just got retard and advanced wrong, not that i was actually going to put the table in the wrong direction.

Offline MadsF

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Re: Help for ignition map needed
« Reply #16 on: March 21, 2017, 04:00:36 pm »


Comments? Map is pure guesswork and estimates with inspiration from other maps for similar engine setups.

1,5 bar of boost
8,7:1 compression
4 cyl
Shell V-power fuel
Stock 530 cylinder 8v head (VX cam)
Stock intake with 875 injectors
T3 TS manifold with Borg Warner S200 turbo (rated 500+ hp)
4" exhaust all the way out

Power goal is 350 hp as safely as possible. Will be used for 201 and 402 m drag (for fun only)

Offline Tille

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Re: Help for ignition map needed
« Reply #17 on: March 22, 2017, 10:46:39 am »
It's save, if your EGT isnt too high. I would add a little advance. I noticed VAG engines with 8.7comp (drilled Audi S2 Pistons) start to knock hard 300kpa,17°Ign, lambda 0,80 @4500rpm and pumpfuel (98 Oktan in Germany). Stay far away from this and it will be fine.




Offline MadsF

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Re: Help for ignition map needed
« Reply #18 on: March 27, 2017, 08:51:29 am »
I will keep an eye on my EGT, if it gets too high, i'll advance a bit.

Thanks for the warning, how did you avoid knock? A bit less timing?
- I can't seem to get my knock setup to work properly, not enough to save the previous engine at least.

Offline MWfire

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Re: Help for ignition map needed
« Reply #19 on: March 27, 2017, 09:35:58 am »
It's save, if your EGT isnt too high. I would add a little advance. I noticed VAG engines with 8.7comp (drilled Audi S2 Pistons) start to knock hard 300kpa,17°Ign, lambda 0,80 @4500rpm and pumpfuel (98 Oktan in Germany). Stay far away from this and it will be fine.
Why so much advance? Is that tunned to knock limit or MBT on dyno?

Offline Tille

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Re: Help for ignition map needed
« Reply #20 on: March 30, 2017, 10:44:59 pm »
It's save, if your EGT isnt too high. I would add a little advance. I noticed VAG engines with 8.7comp (drilled Audi S2 Pistons) start to knock hard 300kpa,17°Ign, lambda 0,80 @4500rpm and pumpfuel (98 Oktan in Germany). Stay far away from this and it will be fine.
Why so much advance? Is that tunned to knock limit or MBT on dyno?

In this case it was knock test.

Offline MWfire

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Re: Help for ignition map needed
« Reply #21 on: March 31, 2017, 08:32:31 am »
It's save, if your EGT isnt too high. I would add a little advance. I noticed VAG engines with 8.7comp (drilled Audi S2 Pistons) start to knock hard 300kpa,17°Ign, lambda 0,80 @4500rpm and pumpfuel (98 Oktan in Germany). Stay far away from this and it will be fine.
Why so much advance? Is that tunned to knock limit or MBT on dyno?

In this case it was knock test.

I did few engines like that on dyno, and no need for that many advance.

Offline MadsF

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Re: Help for ignition map needed
« Reply #22 on: May 26, 2017, 07:04:11 pm »
To future readers .... This ignitions map works fine on a Volvo B230FT engine with a S200 turbo and 1,5 bar running Shell V-Power, IAT arround 30 degree c above ambient, AFR is arround 11,3.

I've burned 300 liters of V-power on these settings, no issues. Max EGT was 820 degree c (full chat on the motorway, usually only high 700)