SCCA RX7 RACER

Hi Again

There are a lot of posts with MSQ programs out there for the earlier versions of Mega Squirt. I have one out there for a street port 2nd Gen MS1 on a V3 board.

Can people post here there set ups for the newer MS3-Pro units to RUN ONLY ROTARY ENGINES?

Looking to shorten my set up and tuning time.

We are all aware that any thing that is posted should be looked at closely to in sure it is compatible with the stuff we are using.

Thanks
Kim

SCCA RX7 RACER

Hi All

Here is a program that people can use. Follow Aaron’s video for the install and testing your wiring.

I am using the latest firmware 1.2.11 off the DIY Tune disc an operating a MS3-Pro unit.
This is on 1986 Mazda RX7 13B NA with resistor pack injectors 460 Primary and 600 secondary (MS3-Pro runs both type of injectors), stock CAS, stock coils, LC-1 Lambda sensor, GM TSP, Water Temp Sensor, Air Temp Sensor, 3bar Vacuum Sensor (DIY Tune).
Engine modification is large street port equal to SCCA EP regulations through header and 3” exhaust.

This set up is for getting you started and driving with slow to medium throttle response. I have not spent a lot of time with it but it has a good idle at. Good cold start (Temp starts at 50 Deg.) and drives with out major lean spots but may be fat here and there. No work has been done on acceleration pump system. All so the set up is set for timing off the map not for setting your timing.
Take note if you are working on a stock engine then try to go leaner on the after fuel set up on cold start and lighter on the fuel table (Try 20% just a guess). If you operating bigger porting run richer to have it start up and drive better.
I had the satisfaction of using a MS1 unit on a V3 board so with my experience going to this was a bit of a test but not too bad. Good news it looks like I will be racing two weeks from now in Oregon in Grass Valley.

Good Luck with your set up and tune

Aaron Cake

iTrader: (1)

You staging is set to RPM only. That's going to cause some major tuning headaches. If you have a set of ITBs (I can't remember off hand) then that may be appropriate but for any other circumstance it should be set to RPM and another load factor (typically KPA).

Also your split table is a bit opposite of typical. In general split should be high at high vacuum, close up near atmospheric, then split again under boost. From there it can be tuned (though that's rather difficult without a steady state dyno, some rotor pressure monitoring, EGT probes, etc).

SCCA RX7 RACER

Hello Again

This is what I read in the MS3-Pro manual (See Below). So I just used the one RPM setting similar to the way I set up my MS1 system. I can see if I use the Duty load factor as a back up it can not hurt. In the past my set up has never had the primary go beyond 75%. and the transition is fairly smooth. (Note still playing with ever thing slowly)

As far as the split table I have a NA engine so I do not factor in any boost. I worked out a safe pattern to keep with related to load and rpm. I have done dyno runs and found that the split timing in my case is not a HP gainer. I do not know about a forced induction system. So again I just stick to what was working from the past. So far no blown engines during the season, buzz 9000 RPM, street port with 200hp at the rear wheels. HP is limited because of intake modifications in my class of racing. If I could do what I want I think there still more HP in the street port.

From Manual:

• Secondary staging parameter - It is recommended that this parameter only be used with forced
induction engines. It should be used to ensure that staging is fully complete before going into
boost so that any lean spots caused by staging are gone.
KIM

Aaron Cake

iTrader: (1)

The manual is generic. Mazda has always used two parameters for staging; RPM and manifold pressure. On the stock engine it's 3800 RPM and about 2" of vacuum. What you'll find with RPM only is that you will end up with a VE table which has a massive cliff at the stage point where you need to pull fuel. And at light load, you may to pull enough fuel. Then again you are probably almost always driving past the stage point anyway so it may not matter.

SCCA RX7 RACER

Yes You are correct I run the car all ways from 5500 RPM to 9000 RPM. We do rolling starts and I start at 5500 to 6500 in second gear depending how fast the pace car is.

muythaibxr

I recommend table-based staging. It's the only way I've been able to get perfect staging in all situations.

Ken

Aaron Cake

iTrader: (1)

I've not looked at table based staging yet as I've always been able to get a good stage using the good old settings. Probably though because most of my installs have a large difference between primary and secondary.

muythaibxr

I can always get 90% there but I always find situations where I can feel it stage or see the AFR go slightly lean with the old settings. In the situations I have tuned, table based makes it entirely seamless.

Ken