SirCygnus

iTrader: (1)

your answer to my question doesnt help me.

pmrobert

Aaron is saying that an MS1 processor isn't able to handle a blended TPS/MAP fueling scenario though an MS2 can. His advice is almost spot on; the MS1-Extra code does have a Hybrid Alpha-N/MAP capability.

This isn't the same or even close to the MS2-Extra code's functionality and were it my expensive metal at risk I'd upgrade to an MS2 processor as there's much more capability in pretty much every parameter.

See http://www.msextra.com/doc/ms1extra/....htm#deshybrid
vs
"More Engine Settings" in
http://www.msextra.com/doc/ms2extra/...n.htm#basefile

There's more to it than my simplistic message, I'm sure Ken can clarify this far better than I.

SirCygnus

iTrader: (1)

how how exactly would i need to set this up?

keep in mind im not using any staged injectors as well.

Aaron Cake

iTrader: (1)

OK, I'm confused as well here because there are two discussions happening in this topic. SirCygnus, if you are using ITBs as mentioned earlier in this thread, then you will probably need to use Alpha-N to get a reasonable tune on MS1. With the long TII intake manifold, you may not need to if your vacuum signal is decent.

If you are turbocharging the engine, then as pmrobert mentioned, you will need to run Hybrid Alpha-N/Speed Density. Alpha-N down low, speed density in boost. I did not check the manual, I only looked for the setting in Megatune and missed the advanced window. My mistake, I was at work and wanted to check quickly.

As for your injector issue, just set the 'Squirt up with both injectors on the primary channel, set two injectors in engine constants, then leave the staging turned off. That way if you decide to stage later on, the connection is there waiting for you without any rewiring necessary.

It would help in answering your questions if you provided some info on your setup.

SirCygnus

iTrader: (1)

ok this helps. also, since im will be runing larger gslSE injectors, is there any particular injector setting i should know about?

pmrobert

I have used two 680/min SE injectors for a long time on my 12A. 1.0ms opening, 10.0 ms reqfuel worked fine for an NA 12A 50x2 ITB setup. I used 5 ohm resistors instead of PWM. They 're just injectors, nothing special. Oh, 4 injections per cycle was rather important as well.

SirCygnus

iTrader: (1)

i dont understand anything you said. how was it all set up?

pmrobert

The information I gave WAS most of the injector settings you need to specify and/or set up. What exactly is it you're asking? Are the abbreviations the part you don't understand?

Aaron Cake

iTrader: (1)

SirCygnus, have you looked at Megatune and the Megamanual? Without that background knowledge, much of the settings we give won't help.

SirCygnus

iTrader: (1)

i have... but not lately ( for two years now)

just the not using the pwm portion is what confused me.

pmrobert

OK, series resistors can be used with low Z injectors instead of PWM. Either way works effectively to limit the total net current through the injector; if you don't, it will quickly cook either the injector or the chip driving it. Using a resistor theoretically results in a longer opening time. However, I have not seen any real world difference. The potential problem with PWM, especially with MS, is that PWM can cause electrical noise that affects the ECU. It's more complex than this and there is a fix requiring board surgery but that's not germaine to this thread. Mazda uses resistor packs inmany vehicles so it's not suboptimal IMO. They wouldn't spend money installing resistor packs if a code change would perform the current limiting as efficiently. Ebay for "RX7 resistor pack" for images of examples. Also, don't take this the wrong way, the current MS hardware and especially software is greatly advanced in many ways from the offerings of 2 years ago. It would be worth your while to read through Aaron's suggested materials to get caught up.

lite blue

This is good information that will help

SirCygnus

iTrader: (1)

also... i was doing some research. it turns out the TURBO 12A's from japan use an intake manifold an tb system. they where fuel injected. i think they had the usual two injector setup.

if you can get a hold of a system like that, im sure it would be a choice setup because maybe, just maybe you could retain all the stock components ( such as mop, and carb hat/filter ) . its worth a look into.

pmrobert

I'm pretty sure the 12AT had injectors in the center iron and used a vertical progressive 3 barrel TB much like the FC's but placed horizontally.

See https://www.rx7club.com/1st-generation-specific-1979-1985-18/jdm-12a-turbo-explained-pictures-lot-pictures-878542/

My install has the injectors immediately after the throttle plates on a wraparound manifold (~16" from the ports) and required a fair amount of fiddling with setings to get WUE, AE and cold idle working well, I'm sure due to the large amount of wall wetting. It probably wouldn't be workable in someplace with traditional cold weather and I'm pretty sure it wouldn't pass emissions during warmup. Primaries in the irons is planned for the next iteration of this engine. Or a 13B.

Jobro

iTrader: (2)

I disagree with Arroncake here. I actually daily drive a street ported high compression 12A using twin 50mm down draft efi throttle bodies. I'm using a Stock 91 rx7 turbo and peak boost is 13psi. Big FMIC 550/870cc injectors, full 3" exhaust. Pod in front air dam, using MS2 ebc in open loop mode.

Car can trap 109mph down the quarter best ET is 13.362 but at less mph.

I have only ever used Speed-Density with megasquirt. I can get a reasonable idle and used to get decent fuel economy before i starting hitting 13psi any chance i get. Staged TII throttle bodies are better than ITB's for economy and low end for sure. I once got 400km from 50L on the EFI'd 12A, best I ever got was 350kms/50L using the ITBs and the car was nicer to drive with the TII intake.

At least when using Speed-Density if you have an overboost condition or vacuum leak the engine will still get appropriate fueling, which is NOT the case with Alpha-N