Nitrous timing help?
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Teching In
Joined: Feb 2017
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Nitrous timing help? So I'm building a fully forged 370 "6.0 lq4 .030 over" with a btr stage 4 cam, edelbrock super Victor with the Holley efi hp stand alone computer with a 250 shot. It's my first time using nitrous so I'm looking for help with injectors and what to do with my timing. Any help would be great
TECH Junkie
Joined: Dec 2012
Posts: 3,614
Likes: 1,326
From: Iowa
You asked about injectors so I'm going to assume you're running a dry kit? I'm gonna skip that question and move towards timing.
Timing can be your best friend or your worst enemy, and it can change from one to the other faster than a politician. With timing, always start by pulling (retarding) timing a little TOO MUCH for what you'll probably end up needing. A multitude of things such as cylinder filling, camshaft selection, chamber efficiency, fuel, etc All factor into timing. So, to be safe pull roughly 2° per 50 shot with an added base of 2° and slowly bring timing back in from there.
In your case, that means pulling 2+ (250/50)*2=12...12 degrees of timing. When I say pull, I mean retard timing that much from whatever the naturally aspirated setup requires. For example, if you have 36° of timing n/a...then you retard by 12...you'll be running only 24° on nitrous.
Yes, pulling 12 degrees sounds like a lot, and it is, but better safe than sorry. Let it be a complete dog for the first few passes until you can get it all tuned up.
Read plugs and slowly bring timing back in until the plugs look right. Also run a proper style plug (Non projected) with the right heat range (probably an 8 NGK). Plug reading is an art in itself that you can read up on elsewhere. You can also look at the wideband if you don't want to read pluga, but it's gonna tell you a very limited story compared to the plugs. Like reading a dr suess book vs a physics textbook.
Timing can be your best friend or your worst enemy, and it can change from one to the other faster than a politician. With timing, always start by pulling (retarding) timing a little TOO MUCH for what you'll probably end up needing. A multitude of things such as cylinder filling, camshaft selection, chamber efficiency, fuel, etc All factor into timing. So, to be safe pull roughly 2° per 50 shot with an added base of 2° and slowly bring timing back in from there.
In your case, that means pulling 2+ (250/50)*2=12...12 degrees of timing. When I say pull, I mean retard timing that much from whatever the naturally aspirated setup requires. For example, if you have 36° of timing n/a...then you retard by 12...you'll be running only 24° on nitrous.
Yes, pulling 12 degrees sounds like a lot, and it is, but better safe than sorry. Let it be a complete dog for the first few passes until you can get it all tuned up.
Read plugs and slowly bring timing back in until the plugs look right. Also run a proper style plug (Non projected) with the right heat range (probably an 8 NGK). Plug reading is an art in itself that you can read up on elsewhere. You can also look at the wideband if you don't want to read pluga, but it's gonna tell you a very limited story compared to the plugs. Like reading a dr suess book vs a physics textbook.
