Megasquirt Help/confirmation

[brianthemagical 1]

hi, first of all i have searched but i just wanted confimation before buy the parts.

 

the plan is to run an 8v with std inlet and TB on MS, probably MS 2 V3, for later conversion to ITB's. i also want to use 4 coil packs on the spark plugs, hopefully with built in ignitors, running wasted spark.

 

now for the questions.

 

1. what type of triger wheel do i need? i think it's 36-1, but what size do i need, 4" or 6 3/4"? and what sensor do i need to use? will the std pug one work?

2. has anyone tried mega view? is it needed of worth while, or just a waste of money, bearing in mind i will have my laptop on long trips.

3. is the stimulator needed? i'm thinking yes, but anything saved is a bonus.

4. if i were to use the above ignition set up, will i need any aditional components to the self build kits, like an extra driver? and how would it be wired up?

5. i plan on making my own loom using the 12' from diyautotune, but i'm unsure as to what i need for the plug. as far as i can tell, i can only find a cover for the plug.

6. will a GM inlet air temp be satisfactory? just poach it from any car that has one?

7. is it possible to control idle satisfactorily with out any external valves and solinoids, even for warmup?

8. which TPS is recomended? GM?

9. how does the map sensor work? i was under the impression it was intergral to the MS and some piping was needed, but i've found some conflicting info.

 

i think thats about it, sorry for the long post and lots of q's. thanks.

[snillet 1]

hi, first of all i have searched but i just wanted confimation before buy the parts.

 

the plan is to run an 8v with std inlet and TB on MS, probably MS 2 V3, for later conversion to ITB's. i also want to use 4 coil packs on the spark plugs, hopefully with built in ignitors, running wasted spark.

 

now for the questions.

 

1. what type of triger wheel do i need? i think it's 36-1, but what size do i need, 4" or 6 3/4"? and what sensor do i need to use? will the std pug one work?

2. has anyone tried mega view? is it needed of worth while, or just a waste of money, bearing in mind i will have my laptop on long trips.

3. is the stimulator needed? i'm thinking yes, but anything saved is a bonus.

4. if i were to use the above ignition set up, will i need any aditional components to the self build kits, like an extra driver? and how would it be wired up?

5. i plan on making my own loom using the 12' from diyautotune, but i'm unsure as to what i need for the plug. as far as i can tell, i can only find a cover for the plug.

6. will a GM inlet air temp be satisfactory? just poach it from any car that has one?

7. is it possible to control idle satisfactorily with out any external valves and solinoids, even for warmup?

8. which TPS is recomended? GM?

9. how does the map sensor work? i was under the impression it was intergral to the MS and some piping was needed, but i've found some conflicting info.

 

i think thats about it, sorry for the long post and lots of q's. thanks.

 

I´ll try to answer some of these, but i must point out that most MS and other aftermarket ECU installs are quite individual depending on what you want to do with the engine.

 

1. Why don´t you use a flywheel from an XU engine that has the 60-2 trigger, it works perfectly for me.

2. Megaview has proven to be a bit "unfunctional" when you´re using the "extra" firmware in the processor, which most do cause it has a lot of good and usabel functions, i personally don´t think megaview is that important, get a sall and nibby laptop thats easy to use incar for tuning and the megaview is not really something you "need".

3. YES, you need the stim, both when building and also if you need to sort something out that´s not working as it should it´s very useful. It´s also a very good way to learn how megasquirt is working and what the signals in makes it do on the output and how the program reacts before you start fiddling with it in the car.

4. Let´s separate the "coil on plug" and "wasted spark" ways of doing things, at first, Coil on plug is normally doned with both crank AND cam position sensor, it wount work if the ECU doesn´t know which stroke the crank is at, if it´s compressing mixture or blowing out exhausts. Wasted spark has 2 coils and each end of the secondary coil is connected to a sparkplug in the 1+4 and 2+3 way and fires the 1+4 together and the 2+3 together, so if cyl 1 is a compressions stroke then cylinder 4 WILL be at exhaust blowout stage, which means the spark on cyl 4 is "wasted", hence the name.

 

HOWEVER, if you have 4 ingitiondrivers, you can connect the "control" inputs to them in pairs for cylinder 1+4 and 2+3 and fire off a coil on plug system as a wasted spark and voilá all you need is a cranksensor.

5. ?

6. Yepp, it´s the easiest way to do it, however you can easily modify the setupfiles for a bosch sensor to if you want to.

7. You can use the "SAD" that´s there from stock on most XU5/XU9 engines from the 80´s, but you´ll be able to get a more precise and reliable control if using the PWM idle setup with, for example a valve from a Mi16 engine.

8. I´ve machined and modified the throttle plate "shaft" and fitted a TPS from an XU5M engine on the housing, but i think there are easier mods then that around...

9. The sensor is normally in the housing, on board the MS mainboard yes, i´ve connected mine with a "T" at the fuel pressure regulator vacuum connection.

[brianthemagical 1]

thanks very much for your replys, now my counters.

 

1. i've got a lightened flywheel thats balanced to the crank, so that would cost more and be detramental to performance. what about the sensor on tha trigger wheel?

4. the plan was to use 4 coil packs, with built in ignitors, i belive some GM ones are as so, and then fire them in paris, as wasted spark. will this work with just 2 igition drivers? the vb912's i think.

5. altered to say, what do i do about a loom, id it just a case of buying the ready built one, like the 12' one on diyautotune?

 

thanks agian for all the replys.

[madspikes 41 1 Cars]

You can use the standard pug water temp sensor, you just need to use some software ( I cant remember the name) to tweek the values in the ecu software. I'm also using a 2nd pug coolent sensor for an inlet temp. This setup works fine.

 

I'm using the throttle sensor from a 306, you can use any 3 wire sensor, the ECU just needs to calibrated to it.

 

For an nice simple install you can use the an Mi or later XU flywheel with the 62-2 pattern.

 

Not sure how the coils drivers would cope driving two coils. Why dont you use the coil pack from a 405. If you get the thermostat housing as well, you can swap the housing with the standard unit. The coil pack then bolts onto the where the dissy would go. All nice and tidy, with no problems getting new HT leads.

 

 

As for the loom, just me one up from scratch., but might be easier starting with a part build loom.

 

Mad.

Edited January 18, 2008 by madspikes

[brianthemagical 1]

hi, thanks for the help.

 

i will be using all the std sensors i can, inc the CLT. i've read that the std CLT isn't the best for IAT, so i'm goin to try and find a specific one.

i'l try and find a 306 TPS, fialing that i'll just make one work.

again with the flywheel, i've already got a lightened and balanced one, and i don't want the hassel of taking the box off, or changing my 4000mile clutch.

i wanted to use CoP to eliminate the the HT leads and i just want CoP, rather than a coil pack, will try and find one though for simplicity. i also want to keep the dizzy for emergencys. can the hall sender on the dizzy be used for anything?

regarding the loom, diyautotune do a plug cover and all the cables correctly labled, which is good, but i can't find the actual plug, otherwise it's the 12' loom.

 

thanks again.

[madspikes 41 1 Cars]

I'm sure there was someone on here, was selling toothed wheels that when on crank pulley, but cant remember who.

 

I think personal I'd use 4 coil drivers, thinking about it. Just get rid of the dissy, have faith in the squrt! I dont think the hall pickup is useful for anything!

 

 

The 306 throttle pot, still needed a mounting bracket on the throttle body. I just used a small bit of ally plate. You might be able to make it out in this picture.

 

 

 

The coolent sensor is a little slow, but it was good enough to get the car running. I do have a new sensor thats going to take its place in the inlet system.... But I have to work a cal out for it.

 

 

Mad.

[brianthemagical 1]

thanks for the reply. i can make out the plate in thepic, i should hopefuly be able to knock something up. would the 4 coil drivers be ok without a cam sensor, or is it still running wasted spark, just MS is firing two of four outputs? i think i'll get 4 anyway, always have some spares, then try and do some learning with the stim. i'm hopefully getting some FETs from maplim which are better spec than the VEMS IGTB's so they should cope even if i did twin up the coils.

thanks again.

[V8Pete 0]

My understanding was the GM coil packs with 'internal igniters' (e.g. LS1) don't require separate 'coil drivers'.

 

See http://www.msextra.com/ms2extra/MS2-Extra_LS1.htm

 

The standard DIYAutoTune loom doesn't have the SPRx wires required for multiple coil control, but they're available on request (and $). The RS Autosports one (also available from Glen's Garage), however does have the SPRx wires, but from memory is slightly shorter.

Edited January 19, 2008 by V8Pete

[snillet 1]

As said above you can have an adapterplate to adjust for the offset in the throttleplate axle, i had it like that at first before i machined a new axle end.

 

You need one igniter per coil if they haven´t got the igniters built in. It is not recommended to use 2 coils per one VB921 because that´ll screw up the current control functions of the VB921 for starters, and there are a few more drawbacks, better of having one per coil then. That is if the igniters, as said above, is not built into the coils which is quite common actually.

 

I´m using the bosch sensors and used easytherm to recalculate the sensortables, but i´ve understood that the GM sensors are actually better calibrated and tends to work better together with MS. I find that mine works very well, but i´ve also changed the bias resistors on the MS mainboard to better suit Bosch sensors which might have an impact on that.

Edited January 19, 2008 by snillet

[brianthemagical 1]

thanks again for all the help, i really appreciate it.

i've looked on glens garage at the loom, looks adequet and i can save $5, yay. thanks for that, i would stil prefer to wire up the plug myself to save some more money but i can't find any.

i'm planning on getting some uprated ignition drivrs so that i can run 2 coils off one if needs be but i am getting 4 just incase it's the only way.

 

will the std pug crank sensor work with a trigger wheel?

tahnks again for the help.

[V8Pete 0]

thanks again for all the help, i really appreciate it.

i've looked on glens garage at the loom, looks adequet and i can save $5, yay. thanks for that, i would stil prefer to wire up the plug myself to save some more money but i can't find any.

The kit comes with an emtpy plug that you can poke wires into etc.

[brianthemagical 1]

thanks for the help, hopefully it'll be order in a few days. thanks again.

[snillet 1]

will the std pug crank sensor work with a trigger wheel?

tahnks again for the help.

 

Can´t see whay i shouldn´t, but there are numerous ways to do that bit if using and external triggerwheel, as i understood that you´re going to do.

[brianthemagical 1]

thanks for the confirmation, i'll see what i find in the scrapyard from a more modern car. thanks again for all the help peeps.