like it says i have an 03 SRT-4 soon to be an evo right now i have the 3inch downpipe w/cutout from needswings. I know for a fact i can run 104 octane but i cant seem to find it all i can find is 110 leaded as of right now i have no cat is it okey to run 110 leaded and what would happen if its not?

 

O2 sensor will not last as long that's all.

 

You can run any octane, but you will not benefit from having race gas alone.
You need to find a way to calibrate your ecu for the fuel you're using.

 

turbo toys work with the 100+ octane mode or so i hope
so the leaded unleaded thing doesnt matter if i run w/o cat?

 

The srt-4 has 2 heated O2 sensors that will eventuially die because of the lead BUT heated O2 sensors do handle leaded gas better than one wire types.

I would just keep looking for some 101 pump or order it from any number of companies on the internet...

 

Use the 110, you won't be sorry. I recently changed from using meth and it makes great power. I changed turbo's too so I really cant give a direct comparison but I can assure you wont be sorry.

 

110 all the way! I'm not a big fan of Meth injection because it's almost like NOS...not always there. I'm lucky cause I have a Shell station 10 minutes from my house where I can get all the 110 I want.
Like they all said 110 with do no harm to your vehicle if you have no cat. You won't benfit from it much unless you can tune for higher boost but make sure you have a wideband to keep an eye on a/f's.
110 octane fuel will cause your car to run a little bit richer than it would with 93 or 91 if that's what you have in your area.

 

i have run 110 leaded octane in my evo over 50 times

no promblems,but your o2 sensor will hate you

 

Thanks you guys rock I'm excited to see my new dyno numbers.