this spring i want more power out of my evo and i am not sure what to do.
i am currently making 395whp @21psi on 93oct with all of mods in sig.
1)should i install an aem ems and turn the boost up to like 25-26psi on pump and also get a race gas tune
2)should i install the hsf-5 meth kit and still run the stock ecu
this is a dd so i need reliability but i also want some decent gains, so as of right now i am leaning toward the aem ems but anybody running either set up please chime in.

 

#1

 

i was talkin to ams about this and they said that upping the boost wit the stock internals wit race gas risks detonation....meth is also slightly dangerous but i would go wit the ems and keep the boost around 22-23..that way...later on down the road you can have the ease of tuning wit the ems and more map storage so u can get separate maps to have meth or race gas and a dd map

 

aem ems

 

asbestos suit is on: dont get meth unless you have the money around to rebuild the engine, doesnt mean it will happen, but you better not be surprized when it does.

 

AEM EMS first, then Alky/Meth. Use them together with a safeguard for a perfect combo. In my opinion you can't tune a stock ecu being safe and aggressive using a alky/meth kit because it will never know when the kit is actually spraying. Latency is a large factor that can make or break your tune and engine, with the EMS you can determine this and advance your tune at the correct point every time. Keep in mind I am not saying you can't use it with the stock ECU but I am stating from my experience it won't ever make as much power or be as safe as it could be if you was using it along with the EMS.

 

The two aren't really the same price, but if you have the money go with the AEM EMS. You will gain power through the midrange from a proper tune. As great as the stock ecu is for ease of tuning, nothing compares to a stand alone.

Also, it will be less wear on the motor. The reason for this is because if you have the AEM EMS first and then get meth later on, you will have more options of tuning it once installed. You can set the EMS to only spray at wide open throttle or maybe just shut it off completely while riding around on the street. It's those little features that will keep your engine from constantly spraying meth, which in turn will provide less wear on the car.

If it's tuned properly, it should run better then ever and be really smooth. A lot of people complain about having issues starting the car or running into problems because it's cold outside and all that stuff. That just means their tuner sucks and doesn't know what he's doing. Don't let any of those stories deter you from getting this while you weigh out your options.

 

Stock ECU is a stand alone. You will gain some power by ditching the MAF and going speed density and tinkering with knock control with EMS, but you'll gain more with meth.

So #2

 

I don't know but if it was mine I'd rather have the compressor side of that 35R upgraded to HTA specs by Forced Performance and step up to a more radical cam profile as well, before doing either of the two mods that you're contemplating.

 

How about turn the boost up to 24psi, tune both for pump and race fuel maps on the stock ECU. And then get a meth kit and run 30 psi daily.

You do not need the EMS to run more boost.

 

If you want an EMS I have a new, unused one for sale............

 

running meth with stock ecu is doable. im doing it and evos in my area are doing it.....the only thing is we cant get really aggressive with it. we gotta leave room for variables that might occur. stock ecu also has safety features that reduced timing and cuts fuel in those emergencies. at least enough to where you can stop the car and pull over to figure out whats going on ...............I would go EMS though if i was planning on doing some BIG BIG power and aggressive tuning.

 

what ^ he^ said.

 

AEM EMS without a doubt

 

Best advice so far IMO (although please up the boost AFTER the tune).