installation of ANY wire-tap syle box (Edge COMP, Blue chip, TST, etc... ) is somewhat "involved" and can/will void your warranty.
The built in gauges are a HUGE plus. Not only do you not have to buy separate gauges, but the box can be set to automatically defuel when a certain EGT is hit-- truly a drive-and-forget it setup. As far as i know, they work fine. You are right to remember the fuel pressure gauge as being all-important.
I have read or followed just about every single power box thread that's been on the 24V section for about 2 years. There are pros and cons to each approach, and some things appeal to different people.
The most bells-and-whistles box is the Bleu Chip Fuel management system. It's the most expensive, the most sophisticated, etc etc. But it's not quick or easy to use necessarily. This box is the "tweaker's" delight. you can adjust fuel enhancement in 1% intervals up to 63% if you want.
The Edge comp is the most popular box. It had 5 power levels with 5 sub-levels each (which control how fast the fuel comes in). I personally feel that the timing is a little too aggressive and don't recommend this particular flavor of the box. Instead.....
The DDUFM-- Diesel Dynamics Universal Fuel module. This is an Edge Comp that has been tweaked to DD specs, so the timing is less aggressive. Also, it will defuel significantly, which will allow you to run truly large injectors on the street. You can get away with larger injectors with the DDUFM than you can with most other boxes. BTW-- the Edge comp will also defuel on its lowest response settings, but not as much as the DDUFM. The DDUFM is a GREAT all-around box.
The TST Powermax lacks a lot of the features of the other boxes (no timing aspect or defueling), but is still an EXCELLENT box. See, the TST doesn't need to do timing, per se, because it tricks the ECM into advancing timing. It's a good thing (imho) to have the ECM controlling timing instead of a box. The TST box (especially in Competition form) will fuel more than ANY other box on the market. If you want Big smoke and big power, the TST will deliver. The TST is the best towing box on the market, IMHO, because it produces so much torque. Generally, the TSTs will make more torque but a hair less "power" when dynoed. They really shine when the engine is being loaded heavily or punished. The TSTs also tend to have slightly higher EGTs than a similar box.
In short, the only 2 fueling boxes i recommend are the TST (which is WICKED in competition tune) and the DDUFM. The DDUFM will run you a tick over $600, while the TST can be had for $549 from many vendors.
Competition upgrades for the TSTs are only like $50, compared to $100 or much more for some of the other boxes.
HOHN NEWS-- I report, YOU decide
Justin
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