SpecE30 and Megasquirt

#1

Jim Levie and I got to talking about this over the weekend. Lets see what others think.

I don’t know a lot about Megasquirt yet, but I’m going to do some research and talk to the outfits that make and sell them. Here’s what I think I know. If you have a background in Megasquirt, pls chime in with corrections or additions.

  1. Megasquirt allows extensive diagnostic logs. This is a big deal. Many of us have torn our hair out for months trying to track down elusive engine problems where it’s missing or otherwise just weak under certain intermittant circumstances. Figuring out this sort of thing is very frustrating and very expensive. Ultimately you end up replacing an ass-load of electrical stuff, spending many hours attacking varius possible causes, and you spend a lot of time and money going to events hopeful that the last set of ideas fixed the problem only to have it reoccur.

Jim chased this kind of problem for 2yrs. He finally fixed it by doing laps with a battery powered oscilliscope. That’s how he spotted the fact that the signal from his CPS was dirty. What kind of shit is that? Is it a reasonable expectation that some of us will eventually have to strap an oscilloscope on to our dash so we can figure out the cause of a problem that is making us crazy?

I had a helova high rpm WOT missing problem at Mid-O last month. Much of the problem got fixed by tightening the alternator mount to the block. The ground quality between mount and block must have been intermittant. But is the DME especially sensitive to voltage at WOT high rpm but not at almost-WOT high rpm? No one knows for sure. We just have reasonable conjecture based on previous observations.

But that missing at WOT high rpm problem was never entirely fixed. I did a ton of work over the past couple of weeks to try to fix it, work I did blind because I really had no idea the cause. All I could do was replace and otherwise address “possible causes”. Saturday morning it was clear I’d not fixed anything because the car was missing at WOT and high rpm that it was so weak it wouldn’t get to RL in 4th gear. Out of desperation I replaced the master relay and the problem disappeared. Holy shit! There was no symptom that my car was having power drop out issues, yet that fixed it.

I had a very intermittant engine problem at RA a couple yrs ago that turned out to be a little fraying on the CPS wire. It wasn’t until the end of the event that I finally figured out what the cause was, so that was one more event pissed away that I can recall off the top of my head.

My point here is that diagnostic logs are a big deal. In a couple minutes you could see on your notebook what is going on at all the Megasquirts inputs. Suspicious of your temps sensor? Look at the input graph. Maybe the CPS signal is dirty at high rpm? Look at the input graph. Suspicious about your TPS? Look at the input graph. Etc. etc.

I think that this has the potential to save a ton of heartache, time and $$. I don’t know how much $$ the MS kit would cost, but I’ve spent a fortune on replacing parts chasing these problems over the years, a lot on hosed events because my car ran like crap, dyno time chasing problems and a fortune worth of wrenching time and aggravation.

  1. MS could fix “chipping”. The current solution is to open up DME’s and look at chips but we’re kidding ourselves if we think that’s rigorous. If we all ran the same MS tune, this could be confirmed in seconds. We just download a guy’s tune, maybe do a checksum on the file and then compare it to a known standard. This could be a far more rigorous tech solution.

Obviously this idea is a bit “out there” for a spec series so folks are going to be pretty reluctant to buy in. But potentially it could go like this…

–SpecE30 types have some agreement in this thread that the idea sounds interesting.
–MS agrees that thier gizmo does what I think it does.
–The SpecE30 leadership agrees to let me run it for a year and collect data, as long as I agree to be DQ’d at all races. The way my year’s going this will be no sacrifice.
–At the end of that test year I report back on what worked well and what didn’t work worth a spit.
–MS agrees to make a plug-n-play kit for some reasonable price.
–Then the leadership decides if the idea is a big enough win such that we should all be running it.

So, your thoughts?

#2

What does it cost? Ballpark.

#3

A valid concern - no doubt… A minor concern I have is the ability to tune other aspects of the motor/fuel (my ignorance makes me nervous here) to take advantage of the MS “tune”…

While I am an advocate of the “don’t change it now” philosophy (and yes this is a 180 on my normal approach) I do see rule changes done as a way of leveling the playing field as good. i.e. in this aspect we’re simplifying problem solving a defunct electrical system to make it easy for us boobs without EE degrees.

I see this same approach for rules effecting tire-wear to keep the series inexpensive from a longterm perspective.

949 Racing in Lake Forrest CA sells a system in the sam vein as the one Ranger descibes for Miata’s/MX5’s and sells it complete for $599

#4

I don’t know. There’s too many variables that would need to be worked out.
–There is a Miata plug n play kit for $600.
–MS would prefer that we not use the stock AFM because it’s pretty antiquated technology. But they can go with it if that’s what we want. MAP sensors are pretty cheap, but this would mean a change to the intake. IMO every additional change is going to make the idea less inviting.
–Apparently the stock O2 sensor can be used. That keeps the price down.
–We ought to be able to negotiate a group discount if in Jan2013 we buy 200 of them.

#5

I have invited the MS guys to this thread to answer questions. I really don’t know what I’m talking about here so I thought it might be best to get some real info.

So if you were just about to post about how you met Mr Megasquirt’s daughter at a party last year and… best keep that little secret to yourself.

#6

i’d rather not mess with the EMS and worry about yet another set of things that could go wrong. just my $0.02

#7

DiyAutoTune.com has a pnp system for the m20 for 430$.

#8

What’s an EMS?

#9

Engine Management System

#10

You’ll change your mind after you spend months tearing your hair out because you can’t find a problem that only seems to occur at $600 track weekends. Having data that would let me be 100% positive that I could rule out all DME inputs as the culprit would be huge. God what a pita intermittant engine performance problems are.

Lets look at what gets replaced when an engine is having intermittant performance problems.
Plug wires $130
Plugs $25
Rotor $60
Dist cap $70
Coil $40
O2 sensor $90
CPS $80
TPS $70
Temp sender $40
Used DME $40
Used AFM $40
Clean/flow injectors $130
Used Engine harness $40

Maybe new engine harness $600
Maybe new AFM $350
Maybe new injectors $380

That doesn’t count the wasted time, wasted events and aggravation.

This idea could make all that badness go away.

#11

Wow, am I really saying this, I think Ranger has a great idea. I have a friend that put MS on a stroked 325I street car and was amazed how few of wires were left after the install. It is a very simple system and has been around long enough to be proven and will probably be here for the long run of support. Our cars are OLD with old stuff on them! Lets not be afraid of new. Maybe something new and different would bring in some more racers. Classes can not remain static, look at the SCCA Spec Racer Ford cars, they remained unchanged for tooo long and it started hurting car counts. I would buy one MS tomorrow if legal. It would make engine swaps a breeze. Plus, it would be very cool. We could develop a great support network very easily.

#12

I hear ya, but rules stability is very important. A change in rules this significant would require a lot of people change shit. What was that count of total SpecE30 types, 250 + a couple dozen newbies each year? 250 x $500 a piece is a huge chunk of change from our community. Not to mention that a lot of us will be paying shops to do the work. Consider also that changes often have unintended consequences, which are my personal specialty.

My point is that no matter how fabulous this idea seems, we need to go in slow and careful, we need to build consensus and we need to test the dogshit out of it.

#13

overall i think the cons of using megasquirt outweigh the pros for se30. but it’s open source and fully supported under linux so i’m on board :slight_smile:

#14

I support a swap to Megasquirt and speed density tuning (MAP sensor) versus the fickle OEM MAF. I also really like the idea of a SpecE30 map that we all have to run that optimizes for the spec exhaust.

#15

You’ll change your mind after you spend weeks tearing your hair out because you can’t find a problem that only seems to occur at $600 track weekends. Having data that would let me be 100% positive that I could rule out all DME inputs as the culprit would be huge. God what a pita intermittant engine performance problems are.

Lets look at what gets replaced when an engine is having intermittant performance problems.
Plug wires $130
Plugs $25
Rotor $60
Dist cap $70
Coil $40
O2 sensor $90
CPS $80
TPS $70
Temp sender $40
Used DME $40
Used AFM $40
Clean/flow injectors $130
Used Engine harness $40

Maybe new engine harness $600
Maybe new AFM $350
Maybe new injectors $380

That doesn’t count the wasted time, wasted events and aggravation.

This idea could make all that badness go away.[/quote]All that stuff on your list gets replaced with new for a proper race car build anyway. If you install a Megasquirt, how many of those items can be directly diagnosed as a specific item? How do you know if it is wires or plugs? The CPS vs TPS? “All that badness go away” is a gross exaggeration.

Regardless, I fully support moving to a Megasquirt. “Someone” will spend the $ (four figures?) it takes to develop it on the dyno. “Someone” will spend that money as soon as it is legal. Others may catch up eventually, but “someone” will be ahead of the curve for a while at least. This rule change can’t pass soon enough.:woohoo:

This solution is not a wholesale cure for what ails the typical Spec E30 build - 25 year old components.

“Plug and Play” Megasquirt = Grand Am ST build that is "just like the cars you drive off the dealer’s lot, right IndyJim?

#16

It will definitely make it easier for me to maximize my 2.8 stroker build I was planning for my return.

I don’t know much about MS aside from the turbo kids like it, any serious tuner I’ve mentioned it to makes a face like a kid with a full diaper and changes the subject. I don’t know if that is good or bad for SE30.

This may seem like a good idea to the guy that thinks of his race car as a science fair project and likes to tinker. It will certainly appeal to checkbook racers that want to purchase that easy HP. Overall I think you may be swapping existing problems for ‘different’ problems.

The engine management on the GA car requires a EE with a masters degree to babysit it and when we had a cylinder down it told us the “back half” of the motor vs. the “front half”. MS wouldn’t have to try very hard to be better than the POS that GA specs, but with an IR temp dealio, or by flipping the caps on the coils I could answer that cylinder question quicker than the dude with the laptop.

Interesting proposal though. I suppose if MS discounted or started sponsoring the series might get even more interesting. Specing a MAP is tough since even across cars there are subtle tuning differences to get it to run properly, there are (at least with the Bosch) some data logging parameters that if used correctly can help police performance.

This should be an entertaining debate…

#17

You’ll change your mind after you spend weeks tearing your hair out because you can’t find a problem that only seems to occur at $600 track weekends. Having data that would let me be 100% positive that I could rule out all DME inputs as the culprit would be huge. God what a pita intermittant engine performance problems are.

Lets look at what gets replaced when an engine is having intermittant performance problems.
Plug wires $130
Plugs $25
Rotor $60
Dist cap $70
Coil $40
O2 sensor $90
CPS $80
TPS $70
Temp sender $40
Used DME $40
Used AFM $40
Clean/flow injectors $130
Used Engine harness $40

Maybe new engine harness $600
Maybe new AFM $350
Maybe new injectors $380

That doesn’t count the wasted time, wasted events and aggravation.

This idea could make all that badness go away.[/quote]
All that stuff on your list gets replaced with new for a proper race car build anyway. If you install a Megasquirt, how many of those items can be directly diagnosed as a specific item? How do you know if it is wires or plugs? The CPS vs TPS? “All that badness go away” is a gross exaggeration.
[/quote]
I’ve changed all those components several times trying desparately to beat problems. The Megasquirt’s input logs won’t tell you that your plugs, wires or injectors are bad. But when the problem is your temp sensor the input logs will make it clear and you replace it. As opposed to the status quo where we have to just start replacing everything until the problem goes away.

Add voltage regulator and alternator to the list. Because I’ve also replaced those chasing this.

Sure, the input logs won’t tell you about every possible problem, but they’ll tell you about a lot of our common problems.

All too often the problem you have at the track can’t be replicated at home in your garage. So when you have, for example, a bad temp sensor it could seem to test fine at home. That’s the devil of the intermittant problem. When you can’t find anything wrong it starts making you crazy because event after event is going by. Being able to check the input logs immed after that “last session” is the best thing that could ever happen to those that have spent time fighting intermittant problems.

#18

[quote=“IndyJim” post=57822]It will definitely make it easier for me to maximize my 2.8 stroker build I was planning for my return.

I don’t know much about MS aside from the turbo kids like it, any serious tuner I’ve mentioned it to makes a face like a kid with a full diaper and changes the subject. I don’t know if that is good or bad for SE30.

This may seem like a good idea to the guy that thinks of his race car as a science fair project and likes to tinker. It will certainly appeal to checkbook racers that want to purchase that easy HP. Overall I think you may be swapping existing problems for ‘different’ problems.

The engine management on the GA car requires a EE with a masters degree to babysit it and when we had a cylinder down it told us the “back half” of the motor vs. the “front half”. MS wouldn’t have to try very hard to be better than the POS that GA specs, but with an IR temp dealio, or by flipping the caps on the coils I could answer that cylinder question quicker than the dude with the laptop.

Interesting proposal though. I suppose if MS discounted or started sponsoring the series might get even more interesting. Specing a MAP is tough since even across cars there are subtle tuning differences to get it to run properly, there are (at least with the Bosch) some data logging parameters that if used correctly can help police performance.

This should be an entertaining debate…[/quote]
If the idea gets a test and we find that it significantly aids troubleshooting and also makes “tuning” harder then we submit it to the leadership for consideration. If we find that it didn’t test out as well as we hoped, then we walk away from the idea. This would be a major change. It would require major testing in order to build confidence that there wouldn’t be bad surprises.

#19

[quote=“Ranger” post=57829]It would require major testing in order to build confidence that there wouldn’t be bad surprises.[/quote]How long is the list of people who want to waste an entire year or two testing Megasquirt and showing up as DQ in the results every time?

If you want some insight into the issues with aftermarket engine management, search the old Spec Miata site for thread about “Spec Miata Turbo” or “SMT”, not to be confused with the Northern California sealed Spec Miata series called SMT.

#20

[quote=“Steve D” post=57831][quote=“Ranger” post=57829]It would require major testing in order to build confidence that there wouldn’t be bad surprises.[/quote]How long is the list of people who want to waste an entire year or two testing Megasquirt and showing up as DQ in the results every time?

If you want some insight into the issues with aftermarket engine management, search the old Spec Miata site for thread about “Spec Miata Turbo” or “SMT”, not to be confused with the Northern California sealed Spec Miata series called SMT.[/quote]
Couldn’t find the thread you mentioned.

Re. how many people want to test. First we see if the community feels the idea is worth looking into. Then we see if the leadership supports looking into it. Then we worry about who wants to help me test.