Ignition timing map help

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wyoung369
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Posts: 4
Joined: Wed Sep 13, 2017 3:07 pm

Ignition timing map help

Post by wyoung369 »

So, I'm in the beginning stages still of actually getting my motor wired and then started. A bit of info, it's a vh45de that will have a single turbo that I'll only be making 3psi with to start. Where I'm running into trouble is ignition timing. I can only find information on the base timing before any advance for the vh45. It's 15 degrees. Now, I don't expect anyone to be able to just tell me "oh if you put in x degrees of timing it will run great and make a bunch of power" but, if I post all the information information about the cams, compression and other factors that I have, can anybody help me come up with an amount of ignition timing that won't detonate or (hopefully) run like total s*** while I break in the clutch and work out the little bugs you inevitably find with a new build?
quan3165
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Re: Ignition timing map help

Post by quan3165 »

Use the base map in the default tune and pull a few degrees from the whole table if you're worried about detonation. You can tweak to find full-power timing on a dyno after you have your fuel dialed in.
Tuning in Houston, TX area
https://www.racebushings.com
wyoung369
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Posts: 4
Joined: Wed Sep 13, 2017 3:07 pm

Re: Ignition timing map help

Post by wyoung369 »

And it should run alright like that? I just gotta put the miles on it to break in the clutch before I can do any real tuning. Sorry if I'm asking any silly questions. I'm learning some of this as I'm going along
quan3165
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Joined: Sat Jul 07, 2012 8:18 am
Location: Cypress (Houston), Texas

Re: Ignition timing map help

Post by quan3165 »

That's what I do with all my builds. Ignition map is usually last to get fine-tuned. Most of your improvements in drivability and power will come from tuning your VE table, just make sure your Required Fuel is correct, including making sure the injector size you enter is correct considering the fuel pressure you are using.
Tuning in Houston, TX area
https://www.racebushings.com
wyoung369
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Joined: Wed Sep 13, 2017 3:07 pm

Re: Ignition timing map help

Post by wyoung369 »

Thanks. I was a little extra worried about ignition timing with the engine being 10.2:1. I know they take boost well. But the few people who have boosted them seem to be unwilling to share anything about their tune
quan3165
Helpful MS/Extra'er
Posts: 106
Joined: Sat Jul 07, 2012 8:18 am
Location: Cypress (Houston), Texas

Re: Ignition timing map help

Post by quan3165 »

Understand. You might look at other pentroof chamber engines as a reference. 28ish degrees at 100kPa at peak torque/power seems typical.
Tuning in Houston, TX area
https://www.racebushings.com
wyoung369
MS/Extra Newbie
Posts: 4
Joined: Wed Sep 13, 2017 3:07 pm

Re: Ignition timing map help

Post by wyoung369 »

This is exactly the information I have been looking for. Man do I wish I had started here. I suppose I will start just a bit below that, break everything in then just monitor egts and pull plugs to get a decent tune before I go to the dyno once I'm ready to make power
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