i've been doing meth injection on my evo for over 2 years i have a full 35r built evo doing 550awhp on 91 with my meth setup. i run 1350cc of meth which is almost double most miatas stock fuel. i am doing a similar but much more scaled down setup on my miata build. meth tuning is tricky depending on how u set up ur system. like they said u cant just jump in and kick up the boost. u need to get a wb and run the kit on ur current settings and adjust in small increments. i was running 28psi on 91 and meth at one point but most can only run 26 it all depends on so many variables ur timing, fuel, meth, mixture of meth, amount of meth, size of turbo plays a big role because the heat and volume of the air charge. my advice get that wideband see where ur air fuels are with the meth, then go up a psi or so until u get to where u want ur afr's to be with no knock. then if u can adjust ur timing accordingly or tweak the afr's a bit more. pm me if u have any questions about meth or forced induction as i have a lot of experience and i hope that i can share my knowlege with this forum.

Sorry, but I totally disagree. And from experience. 15 psi for an extended amount of time (30-35K) = ring wear. I developed massive blow by. Rods are perfectly fine.

Share your knowledge in threads that aren't 9 months old, chief.