[TUN3D]

1forI > The notion that the flash is "only" for upgrades or power-gains is a little misleading.

For my current build, as an example, I'm not running upgraded snails...or meth. My city has 93 & e85 all over the place. The JB4 alone can handle about 3-5 gallons of e85 before it shits all over itself. Meaning...runs way too lean, error codes, limp mode, etc.

This happens because the fuel adjustment scale of the JB4 is limited. You also can't adjust timing properly to compensate for the higher octane levels produced by blending gases/adding meth.

That's where the flash comes in. It doesn't produce any more power per say (again, if used in conjunction with a piggy-back). It simply switches the basic fueling/timing responsibilities over to the DME where there is unlimited room for adjustments.

In your case, with 91 & 4-gals of e85 -- you're fine. In contrast, I run 93 & 9.5-gals of e85 -- that's why I have to use it.

Meth will defiantly help you in terms of raising your octane levels (not to mention the added cooling benefits). That said though, being that your on 91, you still have some room to play with. Try adding 5-gals of e85 and see how your car does. Log and post the results on n54tech.com. If it does well, try 6-gals -- rinse and repeat.

The idea is to push it gradually and find the threshold of what your car can handle on the JB4 alone. As soon as you hit the wall (which your car will tell you BTW), just scale it down gradually -- find the sweet spot -- to where it runs well.

Once you get there (and perhaps want to keep climbing)...that's when you'll need to evaluate the situation and decide on a flash, upgraded LPFP, etc.