Originally Posted by Nick_d_TII (Post 10178676)

Never Used a Haltech or a MS, but I have been using an rtek for over a year or two now, with good results.

I'm running a S4 Hybrid TO4b turbo, with 680x1000cc injectors with a SRT-4 FMIC with a RTEK 2.1. My first dyno at stock boost with minor creep ~7-9 psi i was at 230 RWHP with 10 AFR's in the midrange (too rich). I am now running ~10-11 psi and figuring about 250rwhp or so. It's fast enough for me currently with the tires it has on it, can spin second by dropping the hammer (probably because of the shitty tires mostly).

Tuning does take some time, but if you had access to a dyno it could be done faster, but using the Palm Pilot to make adjustments takes quite some time because you have to edit each perameter one at a time. Just to input the timing maps I spent over an hour and a half just sitting there pluggin in the values. Almost every time I drive it I log, then review on the Computer, then make adjustments to fueling. It still runs rich.

But to be able to send my ecu in and have it sent back in a day or two and just plug it in and go was great. Very user freindly for a Novice tuner who doesn't want to pay someone and would rather learn to 'tune' themselves and who doesn't want to worry about wiring and tuning just to get the car started/running.

This guy made +400HP on an RTEK.
https://www.rx7club.com/time-slips-dyno-128/dyno-sheet-update-916752/

There are multiple people I think that are making around 300hp on an RTEK 2.1.

If you have moderate goals 300-350hp then I would recommend the RTEK.