I'm thinking of rebuilding my C1 with JDM ITR pistons some time in the future to give a static CR of 11.3 to 11.4. I know that it's not a good idea to run high compression without good air-fuel tuning, but then again you can't really dyno tune until your engine has been broken in. So what exactly are you supposed to do to avoid detonation during the break-in? I was thinking that octane booster could be used, but I don't know if it would have any negative effects on the new engine. Any insight?
new engine break-in and tuning
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That's actually a really good question as running the engine too rich or too lean for too long can have negative effects on the break in period,but beating the piss out of it on a dyno is no good either.SO what is the compromise to make here? I have been wondering the same thing, maybe someone with more experience can take this one.
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you run slightly rich and the middle of stock timing during break-in.
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You just crank up the fuel pressure regulator, right?
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I ran 310 injectors and a Bosch fuel pump from a Porsche 911 so I was already running pretty rich on 12:1 CR with stock FP and ignition timing.
You can retard the timing down and turn up the FP. It really depends on the injectors and pump you're using and the CR.
11-11.4:1 is what the JDM ITR's run and so with an ITR pump and stock injectors you can run the lower end to middle of stock ignition timing if you're worried.
You can retard the timing down and turn up the FP. It really depends on the injectors and pump you're using and the CR.
11-11.4:1 is what the JDM ITR's run and so with an ITR pump and stock injectors you can run the lower end to middle of stock ignition timing if you're worried.
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My builder told me not to run to rich during break-in, because too much gas can wash away the lube used during assembly. Therefore the rings won't seal right. That's what I was told.
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your builder is right.
I used the adjective slightly on purpose . Each word I choose has meaning and precision.
your builder will agree that it's preferable with 12:1 CR to be too rich than too lean.
most people retard the timing just to play it safe. I ran stock 16 degrees BTDC and 40 psi vacuum off FPR and was plenty rich.
you have to read your plugs but as you know on a break in you start with a low rpm ceiling any way and so easy to get into the right ball park on the safe side of you fuel tuning.
I used the adjective slightly on purpose . Each word I choose has meaning and precision.
your builder will agree that it's preferable with 12:1 CR to be too rich than too lean.
most people retard the timing just to play it safe. I ran stock 16 degrees BTDC and 40 psi vacuum off FPR and was plenty rich.
you have to read your plugs but as you know on a break in you start with a low rpm ceiling any way and so easy to get into the right ball park on the safe side of you fuel tuning.
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