Chris White

Hey, the phone just rang….Dan, that you?

This story should have a happy ending with Dan installing his MID sleeved engine in about a month!

Chris White

DanG

Once the check clears, I think I'm going to be really happy with going this route. (Don't worry, the check will clear)

I wasn't planning on starting with such a modified 951, but everyone and their mom agrees its cheaper to do things right the first time, instead of dumping a grand or two here, another grand or two there...

So here's the current plans for the engine:

2.7L (104mm) MID sleeved block
ported head w/ late NA cam and upgraded valve springs
K27/8 turbo
either 72 or 84 lb/hr injectors
adjustable FPR
Megasquirt fuel/spark management, tuned by ~me~

We'll see what changes I make to that list before this project is complete.

Dilberto

I have a set of near-new balance shafts, with covers and a late(86-up) oil pump if you need them. PM me if interested...

Zach

Chris White

Balance shaft covers are not interchangeable, especially the ones with integrated bearing caps!

Chris White

macnewma

Dan, why the K27/8? I thought you were going to do it right from the start. I would either have Chris size you a turbo or talk to John at Vitesse. I think David Floyd has a Vitesse turbo sized for his 2.8l.

Also, how do you plan to setup triggering on your MegaSquirt? Are you doing EDIS? Will this be MSII?

Good luck and keep everyone up to date on your progress.

DanG

Its already in the car thanks to a PO with some deep pockets. I'll start out with it, if it becomes an obvious weakpoint, I'll trade up to something better.
I'm looking at my options for this. No-brainer choice would be to buy a 60-2 Tec-3 style triggerwheel, sensor, and mount from Chris. I'm also brainstorming a cam mounted trigger wheel (since I won't need the rotor/cap anymore). I could either go with 180 degree separated missing teeth, or run a plain 36-1 EDIS style wheel and pretend the car is a V8. This would fire a COP setup sequentially. So far sequential COP hasn't been coded out for a standard trigger setup, but you can just do wasted spark COP. (or dino-style coils, boring!)

Haven't decided whether to use EDIS or just fire some coils directly from the MS. I'll probably hold off on MSII until they code out the current features on the MSnS-Extra firmware. Its only a $75 upgrade once the coding is hashed out to my needs. Once the CAN stuff comes out, then the fun will really begin!

macnewma

That makes sense. It is much easier to switch turbos with a standalone (no chips to burn).

From my research, the current version of MSnS-Extra or MSII won't work with a 60-2, but I could be wrong. I would talk to Chris about setting up a 36-1 EDIS wheel in the same fashion he does the 60-2. I think the EDIS setup is great due to its simplicity. It is wasted spark and not full sequential, but it really doesn't matter.

If you figure out a good way to setup triggering let me know, I might give the MS a run just for grins.

Fen

Just been down the trigger route with my Autronic. We ended up fitting a hall sender to the front of the block looking at mild steel tabs we welded to the back of the PAS pulley - there's an unused M10 thread that could have been made for it in there.

For the cam it wasn't so pretty but we managed to attach a mild steel trigger to the face of the cam pulley. I still have the stock dizzy so we mounted a reluctor (from a 964 I believe) through the inspection hole - had to TIG a bracket on for it though.

I think that was easier than finding a way of mounting an EDIS wheel (although they do look cool) and it's all behind the stock belt cover / dizzy cap.

The engine fired last night and the software seems happy with the triggering which is reporting as rock-solid up to 2,000rpm or so which is enough until we get fulling sorted out and get a few miles on it.

DanG

MSnS-E can decode a 60-2.

http://megasquirt.sourceforge.net/ex...ect.html#wheel

The hardware/firmware has the ability to decode a cam-only trigger setup, but I don't believe anyone has gone that route so far. I don't see any negatives over a crank mounted trigger, and it has the advantage of being able to determine exactly where each cylinder is in the 4 stroke cycle from a single sensor.

I do agree though, EDIS seems like the least amount of re-engineering. A complete ignition system that just takes orders from the MS brain. I'll have to see how well the built in coil drivers on the new V3.0 pcb I'm soldering up work. Eliminating the EDIS box entirely has its merits as well.

I drive past the home of Eric Fahlgren (Mr. Megatune) every day on the way to work. He's offered to help me get MSnS-E running on our odd-fire VTwin (possibly turbo'd) FSAE car. I'm sure he can help me get the 951 working too.


Fen, sounds like you've got things working pretty well. Can you post up some pictures of your trigger mounting solution?

macnewma

Dan, I stand corrected. I would say a 60-2 crank trigger would be a good way to go. It would be great if you would document your progress on the 951 Megasquirt setup as you go. I am sure a few of us would like to give it a run.

I have heard some people mention that cam triggers aren't as accurate as the crank trigger. I haven't looked into this to see why though and I am not even positive it is true.

DanG

Well tooth for tooth, the cam trigger needs twice as many to equal the resolution of a crank trigger. But in the case of the Megasquirt, you only need a 4-1 wheel on the crank to run wasted spark. Thats right, just 3 triggers (and a missing one). Any 4*n - 1 (or -2 for the higher n's) will work, up to about 60-70 teeth at 7000rpm or so, when you start exceeding the trigger event input speed. MS only looks at 4 (-1) of those teeth to trigger off of, all it does with the intermediate ones is count them to see when the next "trigger tooth" is coming. It does not make any actions based on the intermediate teeth.

I will keep a good record of my progress. I suspect if I have good results, at least a few guys will start running MS for fuel-only control, or make the step to MSnS. There is already some good 951 MSnS info in these threads, mostly pioneered by DarkLightning...

http://www.msefi.com/viewtopic.php?t=5474

https://rennlist.com/forums/944-turbo-and-turbo-s-forum/214251-stand-alone.html

Also, Dark's page detailing the research/testing he's done so far...

http://www.darklightning.com/msns/

Fen

I'm back in the workshop in the morning so I'll try to remember to take the camera with me.

I think the cam being less accurate than the carnk trigger is because of the half roration speed as said but also because there is a certain amount of flex in it being driven by a belt.

theedge

There is also the ksp guy and his setup, I think thats the route im going to try. Its a PIC microcontroller that will let the MS use the stock sensors. Works on the Audis perfectly.

DanG

You think that might be the same thing Rage was talking about here???

https://rennlist.com/forums/showthre...96#post2038296Without a doubt, I'd pay $100 to be able to use the stock sensors to generate a useable trigger input for individual COP control, and I guess I wouldn't complain if it could only do wasted spark. I'd also be more than happy to build my own from someone's component list and schematic for $12 or whatever.

If this could be done that cheaply, there would be a lot of happy stand-alone 944 owners.

Fen

I don't understand how it can use the stock sensors - there is no stock cam sensor.