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My Dad blew the engine on his moho a few weeks back. He had 3 cylinders that either needed sleeving or boring. He opted to bore the entire block 30 over. As I thought about the reinstall I started to wonder about the ECU. It's a 97 460 with fuel injection. Is he going to need to tweek the computer or with just cylinder boring will it matter? Shadow?
 

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My Dad blew the engine on his moho a few weeks back. He had 3 cylinders that either needed sleeving or boring. He opted to bore the entire block 30 over. As I thought about the reinstall I started to wonder about the ECU. It's a 97 460 with fuel injection. Is he going to need to tweek the computer or with just cylinder boring will it matter? Shadow?
Unless other changes were made during the rebuild (higher comp, more cam, etc), the ECU will have enough range for slightly different parameters.
 

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Unless other changes were made during the rebuild (higher comp, more cam, etc), the ECU will have enough range for slightly different parameters.
Agreed! :)
The inputs will all deliver info to the pcm ,mass air flow,air temp intake,throttle position,etc and the pcm will adjust and deliver outputs timing,fuel etc.
 

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would larger injectors help keep the engine running at full potential as well as prevent the engine from running lean?

I understand the computer will adjust for correct timing but if the injectors do not flow enough the engine could potentially lean itself out under hard loads.

Not sure if 30 over will max your current injectors but definitely worth looking into.;)
 

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Just drive it like you stole it... :D

.03 over isn't going to affect it adversely. I'm not an expert but, the factory ECU should be able to compensate for these small changes with no worries...
 

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would larger injectors help keep the engine running at full potential as well as prevent the engine from running lean?

I understand the computer will adjust for correct timing but if the injectors do not flow enough the engine could potentially lean itself out under hard loads.

Not sure if 30 over will max your current injectors but definitely worth looking into.;)
In a closed loop system, the O2 sensor input will let the ECU know if it needs to richen or lean out the air/fuel ratio (reader's digest version). This is done by changing the injector pulse width (how long it kept open). A bigger injector would only help IF the injector is unable to flow enough fuel at the ECU's max PW. This is highly unlikely unless the engine's fuel requirements have been increased significantly due to other changes or a component malfunction.
 

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No worries

The computer will adjust as required. If a computer controlled fuel system can compensate for changes from sea level to Denver, it can certainly adjust to a few extra cubic inches... Ray
 
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