I'm not sure I want to go near high 11s on an old classic with cast pistons. High 10s are a safer bet. High 11s with fresh forged internals maybe.
When mapping, after calibrating any different MAFs/MAPs/Injectors from stock, I set the AFR map (to 11:1 on my car, I know some mappers go richer, ensuring good AFR tracking on the WB) pull out a block of on boost ignition from the base map (Z4), set the boost and solenoid duty (based on experience and how far you want to go), log max load and rescale the maps with a load axis accordingly. Then slowly increase the advance to 'sparkly' and back it off a degree or two when that point is reached.
I advance the ignition rather than lean it off to achieve power. (3-4 bhp per deg adv at best VE).
The parallel fuel rail sounds good in principle, but you only save a small amount of slippery fuel pipe that I doubt will be causing much head loss (I havent done the calcs, I need some more numbers before I could get into the fluid dynamics of it). The FPR will maintain pressure in the line over all the injectors. I'd be convinced if someone had put 4 lambdas on a car at the cylinder head exit and proved that there was a lean off with the standard fuel setup but to the best of my knowledge they haven't (as it would be a balls ache of a project). Until then its just it remains in the category of nice idea.
The 2 EJ20s I've rebuilt ran a bigend on number 2 and chewed a ring land on number 4. Never had a cyl 3 failure (though not a big sample admittedly!)
As Dunc says, a detalarm is the most important bit of monitoring gear to have, especially on an older tuned car. Det is your enemy, and no matter what the cause, be it running lean, too much boost, too much advance, this is the bit of kit most likely to save an engine.
dynamix wrote:It is def worthwhile getting the parallel fuel rail if you are going for an aggressive tune. Generally speaking if you are looking to get high 11's AFR (Air to Fuel ratio) for power then that mod gives consistent fueling across all four pots. Best power comes from running slightly leaner, but this runs a huge risk of detonation. Therefore most tuners go for AFR of low 11's on subarus on normal pump fuel.
The uprated/adjustable Fuel Pressure Regulator will help gain the safety margin by allowing you to run at higher fuel pressure and therefore get more petrol into the engine when needed. I run one on mine and it helps make the best of std injectors.
A DetAlarm/Knocklink is essential for tuned classics and a great idea for new age subaru (or any other car come to think of it) - they do look a little clunky on the whole but if you look at what DaOne has done with his, it doesnt have to be that way.
11:1 is good, any leaner is bad on stock internals.
