Rotory split, E-85,..... questions
 

Okay I have an 87 TII Street port with stock 550 primaries (cleaned bt RC Engineering), 720 greddy secondarys, ported wastegate, Rtek 1.7, 3 inch dual full exaust system from the group buy, and a rebuilt motot with ~4,000 miles on it. The car is over due for emissions and I'm getting hounded by city code people(because of the old man across the street doesn't like rotary music).
The car back fires and bucks over 5,500rpms. I asume the motor is running rich, but not sure. It did this before the rebuild as well.

My idea is to take use MSII to run flex fuel to pass emisions and run more psi with less retard when when I change the turbo system. How viable is this Idea? I asume with 15 percent of the hydro carbons you'd have up to 75% drop in emissions. Oh yea I've downloaded the megatunix and megatune many times from different sources and have different versions but can't find the option for rotary split. Rigt now I'm in Auto Electrical I and we start ignition systems July 5th so I have a little expierence with auto electronics. Emphasis on little.lol My imediate goal is to pass emisions as soon as possible.

BTW no smog pump on the car either. We have a chasis dyno and a machine to test emisions in class so I'd like to test the power and emision results of the leading and trailing splits. Very interested in muythaibxr's post.
https://www.rx7club.com/megasquirt-forum-153/megasquirt-s5-2nd-gen-fully-stock-ignition-works-455340/
About fuel economy and efientcy of having at no split at idle to run leaner mixtures and split in the mid rpm's. I want to see what the dyno point to.

the MS2 doesn't HAVE any options for rotary split. It's unsupported as of right now.

The msns-extra firmware on the ms1 chip supports rotary, but you have to copy the right msns-extra.ini to the right place, and set up megatune correctly in order to see it.

msns-extra doesn't support flex-fuel however, but it should work fine if you know ahead of time the mix of ethanol to gasoline. However, you can't just switch between regular gas and E85 without changing maps.

Back from the dead...

Does msns-extra code, either ms1 or ms2 based, support flex fuel now?

MS2/extra has whatever support for it that ms2 had. There's nothing special there for rotary split though.

Ken

so ken your saying that ms2extra 2.1.0 doesnt support rotary split. (leading fires first then trailing)

Ive looked, and havent gotten a very clear answer on where the MS2/extra is now with timing split. I do recall split timing, including negative split was in testing, but I dont know where it stands now.

No, I'm saying it supports rotary split, but there's nothing special about rotary split with reference to flex fuel.

Ken

Thanks. I didnt mean to ask if there was anything special for flex fuel for a rotary, just that you could run the flex fuel sensor with the version of ms2extra code that supports leading and trailing rotary ignition. I really like the idea of running a boosted rotary on e85.

If you're going to run E85 all the time, you don't need to be concerned about a special E85 mode. Just retune the fueling and timing for that fuel, be certain that you have enough fuel supply capability (injector sizes, pump capacity, etc.) and you're good to go. The Flex Fuel sensor you may have seen is to allow the ECU to change things on the fly depending on the specific E% in the tank at a particular time, much as would be expected if one were using a varying mix dependent on what the last fuel fill consisted of.

Right. Theres only 2 stations that sell e85 within 100 miles of me, and both are about 20 miles from my house. But that being said, Im still leaning more towards a dedicated tank and pump for e85, and just use table switching. This project is still a little ways off though, I dont even have the car I plan to use it on yet...

uh... the actual amount of ethanol will change depending on the season, in the winter E85 is actually only E70 because ethanol doesnt vaporize very well in the cold. In addition, blends from different locations may have different concentrations too. Basically unless you only use the E85 at a certain time of year, from a certain area, it wont work or you'll need much different maps from one time of year to another.

Oops! Forgot about the blend changes most of the world experiences in winter. Here in South FL a reliable contact at the blending point tells me that E85 doesn't change due to the mild winters we get. Thanks for the reality check.

-Mike