chevybayboy

iTrader: (6)

Ok so I'm rebuilding my 346 into a 383 stroker I already have a base tune on it from the 346 do I need another base tune on it for the 383 bigger cubes just to break the motor in or should I be fine with the 346 base tune?

joecar

The 383 is going to pull in more more air.

dodson55

iTrader: (18)

if all you are going to do is drive it it should be fine but I wouldn't get on it but it should get you by for a few hundred miles until you get it tuned

chevybayboy

iTrader: (6)

OK cool I just want to break it in, so I might have to do a few 3/4 throttle to set my rings i should be ok though right

Ferocity02

iTrader: (60)

The fuel trims should keep the fueling correct as long as they aren't maxed out, but only in closed loop. If they are maxed out you should get a DTC. In open loop the fueling will be too lean assuming the 383 ingests more air than the 346. So, if you must drive it around then do so in closed loop, as in wait for it to warm up first. Do not get into the throttle or else it enters open loop power enrichment which will be too lean. I don't think the learned fuel trims correct in PE mode. Could be wrong though.

chevybayboy

iTrader: (6)

So what do you think I should do to break the motor in?

LS1MCSS

iTrader: (18)

You should get a tune so the pcm at least knows what size motor you have.

joecar

What cam do you have...?

Increase VE table by 10-15%.

Edit IFR table to match injectors (and FPR reference if you added an FPR).

Make sure PE enables (see PE Enables from 2002 Camaro file).


This engine is NA...? During break-in watch trims and wideband, as you open throttle up (to load/seat rings) make sure it runs safely rich (no leaner than 13.0-13.2) and not overly rich (no richer than 12.2-12.4), listen/watch for knock, watch exhaust for smoke.

You don't want to run lean at load and you don't want to wash down the cylinder walls/rings, and you have to get the rings seated shortly after the first startup (you can't drive it around or to a tuner).

joecar

Going to PE from CL, the learned trims are applied (only if they are positive)(i.e. negative trims are first rounded up to zero).

chevybayboy

iTrader: (6)

I was going to keep the same size injectors in the stock 28 until I broke the motor in... guess I'll get a wide band ... so what are youR suggestions On breaking it in and getting the rings to seat properly?.. I'm getting custom cam a little bigger then the torque v2 I had a base tune on for the torque v2 until I broke my clutch in then my bottom end went so decided to rebuild to 383