I'm going to be buying/building the MS1/V3 kit for an 88 TII engine thats being built, and just wanted to check a few things.

I will need the MS1/V3 kit itself, as well as an additional LM1815N for the CAS.

Are any of the VB921 coil drivers necessary? I dont see mention of them in any of the rotary write-ups.

To attach an Innovate LC-1 wideband, is anything additional needed?

The S4's TPS is basically just a switch compared to the S5's, will it still work?

For final power goals of ~300 at the engine, what size injectors would be recommended (since the megasquirt can run them at over 65% duty cycle)?

Is a fuel pressure regulator needed?

I just want to get the list of stuff done so I can get this built by the time the engine's ready

 

You don't need vb921's.

For the LC-1, just run the 0-5v output from there through a resistor (I think I used ~400 ohms ) before connecting to the MS.

You don't need the TPS for anything except maybe fuel cut and idle advance... Accel enrichment can be done using MAP.


you need the whole lm1815 circuit for the G signal on the CAS, and 3 4.7K resistors for the pullups on the LEDs to run ignition.

Fuel pressure regulator is up to you, I've always used one. I would size the injectors so that 1) The stock primaries are used, and larger secondaries are added, 2) total duty cycle is 80% or below. I don't know off the top of my head what size the injectors should be.

Ken

 

Do you have a reason for keeping the stock primaries? if say, 720s were used in the primaries, couldnt the extra just be taken out of the fuel map to account? How does megatune account for the secondaries coming online? is it at a set RPM, and then fuel flow is split between the two sets?

 

http://rx7.com/cgi-local/2ndgencalc.cgi

4x720's should do the trick if you wish to go that route. If you upgrade secondaries only, you'll need something like 1000 or larger. Most seem to go with those modified Ford 1600's since they're inexpensive. Both options will work, but smaller primaries give better control at idle. This advantage is less significant if running hi-res code, or MS2.

Check the documentation for a full description of staged injection operation.

 

as renns says, my reason for suggesting smaller (stock) primaries was to make it easier to control idle and low-load behavior.

ms2/extra does not yet support rotary trailing (although ms2/extra, which is still in alpha, supports staged injection with microsecond resolution, and I've started on the rotary trailing code). The hires code would help you if you wanted to run the larger primaries, but even then, it's easier to control low load and idle AFRs with smaller primaries.


Ken

 

Ok, that makes sense, I was thinking about it to make a smooth transition from primaries to primaries and secondaries and back. 550's and 1600's seems like quite a split, and i wasnt sure how they would be controlled across the transition to avoid stumbling or hesitation. Do you think that this would be a problem?

Thanks for the site btw, thats a cool little script. 550's and 1600's definately leave room to grow, hopefully there wont be a problem in there.

 

so this is everything I need to have a standalone system (don't want to buy a stock TII ECU)??? I'm doing a S5 TII swap what else would I need to make the motor MS compatible.

I'm thinking about just using the S5 NA harness or should I make my own harness?

I was thinking about 550/770cc injectors and an upgraded fuel pump. do I really need a fuel rail?

goal is 230-270 HP

 

What are your plans to drive the electric S5 OMP?

Either way will work. It might be cleaner to start from scratch, that's up to you.

Stock rails are fine.

 

good question ... any suggestions?

 

I'd look into swapping in S4 front cover and OMP. Compatibility issues if any for that swap should be well documented on this forum.

 

renns is right on the s4 front cover, or you could eliminate it and go premix.