Breaking in engine

Rich550 · Post by **Rich550** » Mon Sep 14, 2009 2:04 pm

I've just rebuilt my Alfa boxer engine (all bearings, honed bores, piston rings etc with slightly raised CR and ported heads) and I've binned the distributor and installed the MJLJ at the same time as installing the new engine/

I've run in briefly to check that I've installed the MJLJ properly and it works (which it does). However I don't want to keep idling the engine and playing with the MAP in the garage until I've run it in properly and seated the new rings.

So my question is, when I break the engine in under load for the first twenty miles, can it harm the engine if the MAP i've installed isn't optimal? I'm configuring the map now to what should be about right, then I'll play with it once the initial break in period is over (rolling road session is planned in two days to get the map spot on).

Any ideas?
Thanks
Rich

NITROPIXIE · Post by **NITROPIXIE** » Mon Sep 14, 2009 9:34 pm

I'm guessing you mean an ignition curve map and not MAP Sensor.

You can only really damage the engine if you apply too much load with too much advance. Especially with a lean mixture. If the engines ignition curve is too retarded then you wont do any damage, just lose power which is safer. And obviously a rich mixture is safer.

What you could do is apply the soft rev limiter at say 4000 rpm just to be extra safe for the time being. This way you can't put the engine under high stress until you think the engine is safe to do so.

Rich550 · Post by **Rich550** » Mon Sep 14, 2009 10:29 pm

Yes, sorry, I meant ignition curve map.

I'll remember to keep the advance settings down for increased load. Max advance will be 34 degrees at 4500rpm, hich will obviously reduce with load.

It's now installed and working with the factory default setting, and I have a basic ignition map ready, but what ever I do I can't get my laptop to communicate with the MJLJ either in the car or on the bench (Vista, serial/USB adaptor). So tomorrow I'll try a different adaptor and even an old laptop with a seriel port if I can find one.

Thanks for the advice Nitro

Post by **brentp** » Mon Sep 14, 2009 11:29 pm

Hi Rich,

Keep us posted on your testing progress. If you're running the MAP sensor'd version of the MJLJ, the factory default map may work well enough for you to do break in. The factory map is downloadable from our "Ignition Map Library".

Regards,

DannyP · Post by **DannyP** » Tue Sep 15, 2009 2:55 am

You know, Richard L, I thought that was you from spyderclub!

Welcome to the dark side of sparks! Dizzys suck!

Rich550 · Post by **Rich550** » Tue Sep 15, 2009 8:14 am

Hey Danny!

Thanks for the welcome - I can't wait to get this up and running! Almost there.