KMead’s Microsquirt Build. Formerly: Looking to use PBS DCNF intake manifold for FI

OK so a bit of a left turn at Albuquerque has occurred. A reference for some of us suggesting a big unexpected change and a different path for the future. Happily this is a good change and not a cataclysm.

Hussien has been kind enough to offer up his notably modified engine which came out of his 87 X and I have wisely taken the bait (avoided my usual vacillation, analysis to paralysis etc). He is toting up the parts and pieces he has that will end up coming with so I can plan what else I need to make the change. Happily he has the intake manifold he modified with the straight in injector fuel rail, parts of the timing system and so on. Apparently not too much Volvo stuff as the ‘Tractor’ has needed parts (just kidding).

Some background: a number of years ago I bought the 1987 red X you see in my signature pic. Buying it was a spur of the moment purchase and entailed some unexpected drama. As it was bought knowing it was a project I have been fiddling with it off and on after driving it around for few weeks after buying it and getting it runnin. So far it has been one of my more expensive Fiat purchases as the transaxle needed redoing (thanks Steve for building the new one), the engine’s injection system was rather less than wonderful along with the manifold studs etc. Anyway, it has sat in my garage for a surprising amount of time, even for me.

So what does this all mean? Well first I need to pickup the engine, finalize the new stuff I need and mate the engine to the rebuilt transaxle I have and of course install it. I will be going Microsquirt with a EDIS coil/controller along with a wide band O2 sensor to keep it all reigned in. Exhaust at the moment will be a Yugo manifold with twin downpipes mated to what will likely be the standard exhaust. Obviously this is what I think now, I am sure I will be adjusting along the way based on what I learn and what am taught by others here.

However all is not lost as I do have two X’s. The ‘nice’ red X and my rather tawdry beater X which I hope to keep as an autocross, track day car more in the Carl line of thinking but with fuel injection. I think that one will go the path of DCNF throttle bodies etc and will be another story.

As I know more I will post up progress here and hope to garner people’s experience in going to a Mega/MicroSquirt system. Thank you for your time and assistance.
 
Sounds like a excellent plan! Looking forward to reading about it. ;)

I'll add a little comment regarding the MicroSquirt setup. Consider not using the EDIS controller for your ignition. The EDIS trigger and toothed wheel are great, but the actual controller leaves a little to be desired in my opinion (the mapping isn't ideal and can't be changed). Instead use the MicroSquirt to control your ignition, with a set of "smart coils". Then you can change the mapping to suit your particular needs and tune it properly. There are several great coil choices to pick from; including COP, CNP, dual twin coils, etc, and all are readily available and affordable - plus easy to configure with the MicroSquirt. Take a look at the MicroSquirt manual to see some examples. :)
 
Sounds like a excellent plan! Looking forward to reading about it. ;)

I'll add a little comment regarding the MicroSquirt setup. Consider not using the EDIS controller for your ignition. The EDIS trigger and toothed wheel are great, but the actual controller leaves a little to be desired in my opinion (the mapping isn't ideal and can't be changed). Instead use the MicroSquirt to control your ignition, with a set of "smart coils". Then you can change the mapping to suit your particular needs and tune it properly. There are several great coil choices to pick from; including COP, CNP, dual twin coils, etc, and all are readily available and affordable - plus easy to configure with the MicroSquirt. Take a look at the MicroSquirt manual to see some examples. :)
Thanks, good points. I need to go back through it again. I expect I will continue with wasted spark approach. I am sure I will have other questions.
 
Thanks, good points. I need to go back through it again. I expect I will continue with wasted spark approach. I am sure I will have other questions.
One neat feature available with MicroSquirt is what they refer to as "semi-sequential". The unit has two drivers, each capable of handling two cylinders. Basically it pairs two cylinders in one batch, and the other two in a separate batch. If you connect the two siamesed cylinders in one batch then you essentially have close to a true sequential layout. This applies to both fuel and spark. But to use it for the spark you need to allow the MS to control the ignition (not EDIS) and use either individual coils or a dual twin coil (like the VW item).
 
Personally I would say discard the lower injection manifold that Hussien modified, and drop the volvo injection module... that engine went thru 4 head gaskets and melted a piston, due to issues with tune and running lean etc before he gave up and went K24.

For what he was asking it's still cheap as you've bought yourself what's probably a good core, with some forged pistons and a tipo head

Stick with plan A.

You can use the plenum off that motor and modify it to suit your original idea, it at least has a larger sized throttle blade, use the megasquirt to run the injection as you had originally planned.

You get to toodle around in with your standard engine until you're ready to swap it over as a complete unit.

SteveC
 
There's some great info in this thread. I'm looking forward to seeing how it turns out.



I'm going to force myself (well, I'll try) to not do any more long term mechanical projects to my running car until the body is restored, but once that's done I'll most definitely be going down this route as well. MoTeC if I miraculously become rich by then, Megasquirt/Microsqirt otherwise.

I was planning to retain single throttle at first, but with a larger throttle bore. I was actually going to use the modified manifold you now have, but I took too long to get around to buying it, and I'm still a ways out, so I'm glad to see someone's getting use out of it.

Your ITB idea is quite enticing, especially considering the greatly improved response they can offer, provided the injectors are placed appropriately. An enclosed plenum of some sorts would still be advantageous for getting air from a single cool source, and the lack of pressure differential across the part would also significantly reduce stresses on whatever fabricated part serves that role, potentially opening up more options for manufacture. However, compared to keeping a more factory-like single TB, the complexity is greatly increased.
 
Sounds like a excellent plan! Looking forward to reading about it. ;)

I'll add a little comment regarding the MicroSquirt setup. Consider not using the EDIS controller for your ignition. The EDIS trigger and toothed wheel are great, but the actual controller leaves a little to be desired in my opinion (the mapping isn't ideal and can't be changed). Instead use the MicroSquirt to control your ignition, with a set of "smart coils". Then you can change the mapping to suit your particular needs and tune it properly. There are several great coil choices to pick from; including COP, CNP, dual twin coils, etc, and all are readily available and affordable - plus easy to configure with the MicroSquirt. Take a look at the MicroSquirt manual to see some examples. :)
I entirely agree regarding ignition. Having full control over spark angle is a requirement to get the most out of a modern engine management system.

I'm a little fuzzy on the whole EDIS thing though, I know absolutely nothing about fords so it's all new to me. I've seen explanations that suggest edis is entirely controlled by the ECU, and others suggesting it's handled internally (but then I'd think it needs some load sensor input of some sort).

Either way, there's a handful of good options out there for direct ECU control as well, which also offers some more freedom in regards to crank and (if equipped) cam sensing.
 
I entirely agree regarding ignition. Having full control over spark angle is a requirement to get the most out of a modern engine management system.

I'm a little fuzzy on the whole EDIS thing though, I know absolutely nothing about fords so it's all new to me. I've seen explanations that suggest edis is entirely controlled by the ECU, and others suggesting it's handled internally (but then I'd think it needs some load sensor input of some sort).

Either way, there's a handful of good options out there for direct ECU control as well, which also offers some more freedom in regards to crank and (if equipped) cam sensing.
I will likely utilize the built in ignition control in Microsquirt as pointed out by Dr Jeff. That is new functionality with the paired injectors as opposed to the batch system MicroSquirt did have.

The ignition maps are good enough for the relatively simple needs of a non turbo engine. Likely to follow the final version Hussien was using which was pretty similar to the Fiat/Bosch distributor. If I use a COP I won’t need an external igniter or the VW type wasted spark coil (which is similar to the EDIS coil) with an integral igniter.

Definitely open to alternatives. Thanks
 
I have this Bosch P65 Motorsport coil on my UT engine, controlled by ECU. A (small) separate ignition module is needed as well. These coils are flexing which makes them fit on our engines.
p65-coil.jpg

I have them mounted on a bracket
IMG_20200505_105618~2.jpg
 
I have this Bosch P65 Motorsport coil on my UT engine, controlled by ECU. A (small) separate ignition module is needed as well. These coils are flexing which makes them fit on our engines.
View attachment 71079
I have them mounted on a bracket
View attachment 71080
Not sure if this is by coincidence or not, but these are the same family of coil that you'll find on the Alfa Romeo 4c- just the hand picked/QC version from Motorsports in your case.

I really like your solution here... I was wondering how well one could implement this style of coil. Is that fitment secure with the plug "wire/tube" bent?
 
There are individual coils (such as those Bosch Motorsport ones) available in two different basic formats; with the "drivers" included internally in each coil (a "smart" coil), or without any driver ("dumb" coil?) that requires a module of some sort to fire them. Some ECU's include the drivers within the actual ECU so they can work with either type. Others ECUs (such as the MicroSquirt) do not include the drivers so you either need to use the "smart" type coils or an external driver (like Bjorn has).
 
Not sure if this is by coincidence or not, but these are the same family of coil that you'll find on the Alfa Romeo 4c- just the hand picked/QC version from Motorsports in your case.

I really like your solution here... I was wondering how well one could implement this style of coil. Is that fitment secure with the plug "wire/tube" bent?
The tube is very tight to the spark plug so very secure. Also, the bracket is pushing and holding the coils in position. For servicing the easiest way is to remove/mount the bracket and all four coils as a single unit. Unfortunately, it is a little bit tricky to check the oil level as the bracket hides the dipstick hole.
 
Personally I would say discard the lower injection manifold that Hussien modified, and drop the volvo injection module... that engine went thru 4 head gaskets and melted a piston, due to issues with tune and running lean etc before he gave up and went K24.
SteveC
Just to clarify, he's not using any of the Volvo EMS. I don't have any of the wiring for that anyway. Hardware is what he's getting from me. I don't see what the issue with the lower runners is, they allow for composite injectors & easy access fuel rail.

My primary issue was timing curve - I foolishly assumed I could use a modded Volvo curve, which did not work at all (hence the HG failures); cutting & pasting the Fiat EFI (mechanical disc. advance) timing map into the Volvo EZK chip was what resolved all that. Interestingly (I suppose), it was excessive mid range advance that was the problem, not so much top end.
 
The talk of timing curves causing head gasket failures genuinely concerns me (and probably should concern kmead and others, too). Is there somehow a knock limitation? Or is there some physical weakness that causes failure if the timing is pushed towards (or slightly beyond, accidentally) mean best torque?

The distributor-based map works well as a baseline, but most of the gain is being able to adjust beyond the bounds of a mechanical system...and stock is absolutely not peak power and efficiency throughout the load and rev range.

Are the head gaskets that terrible?
 
The talk of timing curves causing head gasket failures genuinely concerns me. Is there somehow a knock limitation? Or is there some physical weakness that causes failure if the timing is pushed towards (or slightly beyond, accidentally) mean best torque?

Are the head gaskets that terrible?
Yes and no. There are various knock limitations and means to sense or control it, but it isn't something that (as far as I know) can be easily defined or resolved for any one specific engine (I'm referring to modified or tuned engines, not bone stock factory ones). Other than utilizing a reasonable timing curve that is safely within limits. So the question becomes what are those limits (which I think is what you are asking?).

In my opinion the best approach is by performing dyno runs with a highly skilled operator and sophisticated (i.e. extremely expensive) knock sensing equipment to experiment with the reasonable limits. That can get expensive, but considering every engine build is different to one degree or another there really are no shortcuts or "cookie cutter" approaches to it.

I suppose the next best approach might be to just go really conservative with the timing. You'll leave some performance on the table but that's better than destroying your engine.

You can try to do your own testing. With a number of "affordable" means of knock sensing and a lot of road testing, with a passenger running the laptop so the map can be tweaked until you feel comfortable. However this is a highly subjective and risky approach. According to several experts I discussed it with, most such knock sensing devices are not very effective. Although for a street driven engine that isn't overly strung it may suffice (assuming the person has some idea of what they're doing)?
 
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