how much do those run about?

 

Turetto says you can run 40psi.......I just talked to him after I got off the phone with Harry's and got my parts overnighted from japan

 

The shortblocks are $1500-$1700 I believe. You can also use the WRX heads, though I don't know what kind of engineering magic you'd need to do.

 

There isn't really a "max", there's just experience and expectations. Like most have said, 19-20 is the most you'd want to run on a daily-driven EJ20 car that's going to risk bad gas, elevation changes, different loads, etc.

You need to be especially careful with a UTEC, becuase you don't have a lot of the factory safeguards that can protect your motor under some of those conditions; change elevations, for example, and you can lean it out dangerously (which is one of the reasons our friends from Reno run Ecutek and Cobb stuff, because it can adapt to altitude without a retune.)

On an STi block, you're probably safe out to 22-24 PSI, but there's a ton of variables, There's CFM in addition to boost levels, what your fueling situation is, added things like water or alcohol inection to prevent detonation, etc.

Any motor can be built to a given boost level, so it's impossible to say with a given set of mods, reinforced rods (from who? forged, semi-forged, cast?) pistons (again, from who? Overbore, skirt design, forged, semi-forged, hypereutectic), crank (change the stroke? forged?) what kind of limits you'll have.

It'd be easier to say you're looking for a given boost level, and then work out what mods will get you there, and remember that it's all hypothetical until you get a particular combo of parts in a car and test it out. Some pistons (hypereutectic) are great combos of price and performance, but have a resonant frequency that destroys them at the detonation frequency you get with nitrous. They'll work great under one set of conditions, but horrible under another.

There are lots of different options out there. If you want to run high boost, neither a EJ20 or an EJ25 is going to be ideal, becuase they're still pretty much open-deck motors. You can sleeve them ,you can reinfornce them, but you're putting bandaid fixes on them. You can build an EJ22, a motor that could handle almost 30 pounds of boost on the bottom end stock, because it's a much stouter closed deck motor.

My point is that there's no way to answer your question except with anecdotal evidence and well-0educated guesses (which, again, come from experience, ieven if it's not first hand. That's what R&D is

 

great answer

 

Ya too much.

 

what about running with methanol vs pump gas?